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<book>
  <bookinfo>
    <title>Frequently Asked Questions for FreeBSD 2.X, 3.X and 4.X</title>

    <corpauthor>The FreeBSD Documentation Project</corpauthor>

    <pubdate>$FreeBSD: doc/en_US.ISO8859-1/books/faq/book.sgml,v 1.411 2002/02/27 05:07:58 dd Exp $</pubdate>

    <copyright>
      <year>1995</year>
      <year>1996</year>
      <year>1997</year>
      <year>1998</year>
      <year>1999</year>
      <year>2000</year>
      <year>2001</year>
      <year>2002</year>
      <holder>The FreeBSD Documentation Project</holder>
    </copyright>

    &bookinfo.legalnotice;

    <abstract>
      <para>This is the FAQ for FreeBSD versions 2.X, 3.X, and 4.X.
        All entries are assumed to be relevant to FreeBSD 2.0.5 and later,
        unless otherwise noted. Any entries with a &lt;XXX&gt; are under
        construction. If you are interested in helping with this project,
        send email to the &a.doc;.  The latest version of this
        document is always available from the <ulink
        URL="../../../../index.html">FreeBSD World Wide Web
        server</ulink>. It may also be downloaded as one large <ulink
        URL="book.html">HTML</ulink> file with HTTP or as plain text,
        postscript, PDF, etc. from the <ulink
        URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/">FreeBSD FTP
        server</ulink>. You may also want to <ulink
        URL="../../../../search/index.html">Search the
        FAQ</ulink>.</para>
    </abstract>
  </bookinfo>

  <chapter id="introduction">
    <title>Introduction</title>

    <para>Welcome to the FreeBSD 2.X-4.X FAQ!</para>

    <para>As is usual with Usenet FAQs, this document aims to cover the
      most frequently asked questions concerning the FreeBSD operating
      system (and of course answer them!).  Although originally intended
      to reduce bandwidth and avoid the same old questions being asked
      over and over again, FAQs have become recognized as valuable
      information resources.</para>

    <para>Every effort has been made to make this FAQ as informative as
      possible; if you have any suggestions as to how it may be improved,
      please feel free to mail them to the &a.faq;.</para>

    <qandaset>
      <qandaentry>
        <question id="what-is-FreeBSD">
          <para>What is FreeBSD?</para>
        </question>

        <answer>
         <para>Briefly, FreeBSD is a UN*X-like operating system for
           the i386 and Alpha/AXP platforms based on U.C. Berkeley's
           <quote>4.4BSD-Lite</quote> release, with some
           <quote>4.4BSD-Lite2</quote> enhancements.  It is also based
           indirectly on William Jolitz's port of U.C.  Berkeley's
           <quote>Net/2</quote> to the i386, known as
           <quote>386BSD</quote>, though very little of the 386BSD
           code remains.  A fuller description of what FreeBSD is and
           how it can work for you may be found on the <ulink
           URL="../../../../index.html">FreeBSD home
           page</ulink>.</para>

         <para>FreeBSD is used by companies, Internet Service Providers,
           researchers, computer professionals, students and home users
           all over the world in their work, education and recreation.
           See some of them in the <ulink
           URL="../../../../gallery/index.html">FreeBSD
           Gallery</ulink>.</para>

         <para>For more detailed information on FreeBSD, please see the
           <ulink URL="../handbook/index.html">FreeBSD
           Handbook</ulink>.</para>
       </answer>
      </qandaentry>

      <qandaentry>
        <question id="FreeBSD-goals">
          <para>What is the goal of the FreeBSD Project?</para>
        </question>

        <answer>
          <para>The goal of the FreeBSD Project is to provide software
            that may be used for any purpose and without strings attached.
            Many of us have a significant investment in the code (and
            project) and would certainly not mind a little financial
            compensation now and then, but we are definitely not prepared
            to insist on it.  We believe that our first and foremost
            <quote>mission</quote> is to provide code to any and all
            comers, and for whatever purpose, so that the code gets the
            widest possible use and provides the widest possible benefit.
            This is, we believe, one of the most fundamental goals of Free
            Software and one that we enthusiastically support.</para>

          <para>That code in our source tree which falls under the
            <ulink url="http://www.FreeBSD.org/copyright/COPYING">GNU
            General Public License (GPL)</ulink> or <ulink
            url="http://www.FreeBSD.org/copyright/COPYING.LIB">GNU
            Library General Public License (LGPL)</ulink> comes with
            slightly more strings attached, though at least on the
            side of enforced access rather than the usual opposite.
            Due to the additional complexities that can evolve in the
            commercial use of GPL software, we do, however, endeavor
            to replace such software with submissions under the more
            relaxed <ulink
            url="http://www.FreeBSD.org/copyright/freebsd-license.html">
            FreeBSD copyright</ulink> whenever possible.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="bsd-license-restrictions">
          <para>Does the FreeBSD license have any restrictions?</para>
        </question>

        <answer>
          <para>Yes.  Those restrictions do not control how you use
            the code, merely how you treat the FreeBSD Project itself.
            If you have serious license concerns, read the actual
            <ulink
            url="http://www.FreeBSD.org/copyright/freebsd-license.html">
            license</ulink>.  For the simply curious, the license can
            be summarized like this.</para>

          <itemizedlist>
            <listitem>
              <para>Do not claim that you wrote this.</para>
            </listitem>

            <listitem>
              <para>Do not sue us if it breaks.</para>
            </listitem>
          </itemizedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="replace-current-OS">
          <para>Can FreeBSD replace my current operating system?</para>
        </question>

        <answer>
          <para>For most people, yes.  But this question is not quite
            that cut-and-dried.</para>

          <para>Most people do not actually use an operating system.
            They use applications.  The applications are what really
            use the operating system.  FreeBSD is designed to provide
            a robust and full-featured environment for applications.
            It supports a wide variety of web browsers, office suites,
            email readers, graphics programs, programming
            environments, network servers, and just about everything
            else you might want.  Most of these applications can be
            managed through the <ulink
            url="http://www.freebsd.org/ports/">Ports
            Collection</ulink>.</para>

          <para>If you need to use an application that is only
            available on one operating system, you simply cannot
            replace that operating system.  Chances are there is a very
            similar application on FreeBSD, however.  If you want a
            solid office or Internet server, a reliable workstation,
            or just the ability to do your job without interruptions,
            FreeBSD will almost certainly do everything you need.
            Many computer users across the world, including both
            novices and experienced UNIX administrators, use FreeBSD
            as their only desktop operating system.</para>

          <para>If you are migrating to FreeBSD from some other UNIX
            environment, you already know most of what you need to.
            If your background is in graphic-driven operating systems
            such as Windows and older versions of Mac OS, expect to
            invest additional time learning the UNIX way of doing
            things.  This FAQ and the <ulink
            url="../handbook/index.html">FreeBSD Handbook</ulink> are
            excellent places to start.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="why-called-FreeBSD">
          <para>Why is it called FreeBSD?</para>
        </question>

        <answer>
          <itemizedlist>
            <listitem>
              <para>It may be used free of charge, even by commercial
                users.</para>
            </listitem>

            <listitem>
              <para>Full source for the operating system is freely
                available, and the minimum possible restrictions have
                been placed upon its use, distribution and incorporation
                into other work (commercial or non-commercial).</para>
            </listitem>

            <listitem>
              <para>Anyone who has an improvement or bug fix is free
                to submit their code and have it added to the source tree
                (subject to one or two obvious provisions).</para>
            </listitem>
          </itemizedlist>

          <para>It is worth pointing out that the word
            <quote>free</quote> is being used in two ways here, one meaning
            <quote>at no cost</quote>, the other meaning <quote>you can do
            whatever you like</quote>.  Apart from one or two things you
            <emphasis>cannot</emphasis> do with the FreeBSD code, for
            example pretending you wrote it, you really can do whatever you
            like with it.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="latest-version">
          <para>What is the latest version of FreeBSD?</para>
        </question>

        <answer>
          <para>Version <ulink
            URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/&rel.current;-RELEASE/">&rel.current;</ulink>
            is the latest <emphasis>RELEASE</emphasis> version; it was
            released in &rel.current.date;. This is also the latest
            <emphasis>STABLE</emphasis> version.</para>

          <para>Briefly, <emphasis>-STABLE</emphasis> is aimed
            at the ISP, corporate user, or any user who wants stability and a
            low change count over the wizzy new features of the latest
            <emphasis>-CURRENT</emphasis> snapshot.  Releases can come
            from either branch, but <emphasis>-CURRENT</emphasis>
            should only be used if you are prepared for its increased volatility (relative to 
            <emphasis>-STABLE</emphasis>, that is).</para>

          <para>Releases are made <link linkend="release-freq">every
            few months</link>. While many people stay more up-to-date with
            the FreeBSD sources (see the questions on <link
            linkend="current">FreeBSD-CURRENT</link> and <link
            linkend="stable">FreeBSD-STABLE</link>) than that, doing so
            is more of a commitment, as the sources are a moving
            target.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="current">
          <para>What is FreeBSD-CURRENT?</para>
        </question>

        <answer>
          <para><ulink
            URL="../handbook/cutting-edge.html#CURRENT">FreeBSD-CURRENT</ulink>
            is the development version of the operating system, which
            will in due course become 5.0-RELEASE.  As such, it is
            really only of interest to developers working on the
            system and die-hard hobbyists.  See the <ulink
            URL="../handbook/cutting-edge.html#CURRENT">relevant
            section</ulink> in the <ulink
            URL="../handbook/index.html">handbook</ulink> for details
            on running -CURRENT.</para>

          <para>If you are not familiar with the operating system or are
            not capable of identifying the difference between a real
            problem and a temporary problem, you should not use
            FreeBSD-CURRENT.  This branch sometimes evolves quite quickly
            and can be un-buildable for a number of days at a time.
            People that use FreeBSD-CURRENT are expected to be able to
            analyze any problems and only report them if they are deemed
            to be mistakes rather than <quote>glitches</quote>. Questions
            such as <quote>make world produces some error about
            groups</quote> on the -CURRENT mailing list may be
            treated with contempt.</para>

          <para>Every day, <ulink
            URL="../../../../releases/snapshots.html">snapshot
            </ulink> releases are made based on the current state of the
            -CURRENT and -STABLE branches. Nowadays, distributions of the
            occasional snapshot are now being made available. The goals
            behind each snapshot release are:</para>

          <itemizedlist>
            <listitem>
              <para>To test the latest version of the installation
                software.</para>
            </listitem>

            <listitem>
              <para>To give people who would like to run -CURRENT or
                -STABLE but who do not have the time or bandwidth to
                follow it on a day-to-day basis an easy way of
                bootstrapping it onto their systems.</para>
            </listitem>

            <listitem>
              <para>To preserve a fixed reference point for the code in
                question, just in case we break something really badly
                later.  (Although CVS normally prevents anything horrible
                like this happening :)</para>
            </listitem>

            <listitem>
              <para>To ensure that any new features in need of testing
                have the greatest possible number of potential
                testers.</para>
            </listitem>
          </itemizedlist>

          <para>No claims are made that any -CURRENT snapshot can be
            considered <quote>production quality</quote> for any purpose.
            If you want to run a stable and fully tested system, you will
            have to stick to full releases, or use the -STABLE
            snapshots.</para>

          <para>Snapshot releases are directly available from <ulink
            URL="ftp://current.FreeBSD.org/pub/FreeBSD/">
            ftp://current.FreeBSD.org/pub/FreeBSD/</ulink> for 5.0-CURRENT
            and <ulink URL="ftp://releng4.FreeBSD.org/pub/FreeBSD">
            releng4.FreeBSD.org</ulink> for 4-STABLE snapshots.
            3-STABLE snapshots are not being produced at the time of
            this writing (May 2000).</para>

          <para>Snapshots are generated, on the average, once a day for
            all actively developed branches.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="stable">
          <para>What is the FreeBSD-STABLE concept?</para>
        </question>

        <answer>
          <para>Back when FreeBSD 2.0.5 was released, we decided to
            branch FreeBSD development into two parts.  One branch was
            named <ulink
            URL="../handbook/current-stable.html#STABLE">-STABLE</ulink>,
            with the intention that only well-tested bug fixes and
            small incremental enhancements would be made to it (for
            Internet Service Providers and other commercial
            enterprises for whom sudden shifts or experimental
            features are quite undesirable).  The other branch was
            <ulink
            URL="../handbook/cutting-edge.html#CURRENT">-CURRENT</ulink>,
            which essentially has been one unbroken line leading
            towards 5.0-RELEASE (and beyond) since 2.0 was
            released. If a little ASCII art would help, this is how it
            looks:</para>

          <programlisting>                 2.0
                  |
                  |
                  |  [2.1-STABLE]
 *BRANCH*       2.0.5 -&gt; 2.1 -&gt; 2.1.5 -&gt; 2.1.6 -&gt; 2.1.7.1  [2.1-STABLE ends]
                  |                            (Mar 1997)
                  |
                  |
                  |  [2.2-STABLE]
 *BRANCH*       2.2.1 -&gt; 2.2.2-RELEASE -&gt; 2.2.5 -&gt; 2.2.6 -&gt; 2.2.7 -&gt; 2.2.8 [end]
                  |       (Mar 1997)    (Oct 97) (Apr 98) (Jul 98) (Dec 98)
                  |
                  |
               3.0-SNAPs  (started Q1 1997)
                  |
                  |
               3.0-RELEASE (Oct 1998)
                  |
                  |  [3.0-STABLE]
 *BRANCH*      3.1-RELEASE  (Feb 1999) -&gt; 3.2 -&gt; 3.3 -&gt; 3.4 -&gt; 3.5 -&gt; 3.5.1
                  |                     (May 1999) (Sep 1999) (Dec 1999) (June 2000) (July 2000)
                  |
                  |  [4.0-STABLE]
 *BRANCH*        4.0  (Mar 2000) -&gt; 4.1 -&gt; 4.1.1 -&gt; 4.2 -&gt; 4.3 -&gt; 4.4 -&gt; ... future 4.x releases ...
                  |
                  |              (July 2000)   (Sep 2000)   (Nov 2000)
                 \|/
                  +
          [5.0-CURRENT continues]</programlisting>

          <para>The 2.2-STABLE branch was retired with the release of 2.2.8.
            The 3-STABLE branch has ended with the release of 3.5.1, the
            final 3.X release.  The only changes made to either of these
            branches will be, for the most part, security-related bug
            fixes.</para>

          <para>4-STABLE is the actively developed -STABLE branch.
            The latest release on the 4-STABLE is
            &rel.current;-RELEASE, which was released in
            &rel.current.date;.</para>

          <para>The 5-CURRENT branch is slowly progressing toward
            5.0-RELEASE and beyond.  See <link linkend="current">What
            is FreeBSD-CURRENT?</link> for more information on this
            branch.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="release-freq">
          <para>When are FreeBSD releases made?</para>
        </question>

        <answer>
          <para>As a general principle, the FreeBSD core team only release
            a new version of FreeBSD when they believe that there are
            sufficient new features and/or bug fixes to justify one, and
            are satisfied that these new developments have been tested
            sufficiently to avoid compromising the stability of the
            release.  Release dates are generally announced well in
            advance, so that the people working on the system know
            when their projects need to be finished and tested.  
            Many users regard this caution as one of the best
            things about FreeBSD, although 
            waiting for all the latest goodies to reach -STABLE
            can be a little frustrating.</para>

          <para>Releases are made about every 4 months on average.</para>

          <para>For people who need or want a little more excitement,
            binary snapshots are made every day as discussed above.</para>
         </answer>
      </qandaentry>

      <qandaentry>
        <question id="responsible">
          <para>Who is responsible for FreeBSD?</para>
        </question>

        <answer>
          <para>The key decisions concerning the FreeBSD project, such
            as the overall direction of the project and who is allowed
            to add code to the source tree, are made by a <ulink
            URL="../../articles/contributors/article.html#STAFF-CORE">core
            team</ulink> of 9 people. There is a much larger team of
            more than 200 <ulink
            URL="../../articles/contributors/article.html#STAFF-COMMITTERS">committers</ulink>
            who are authorized to make changes directly to the FreeBSD
            source tree.</para>

          <para>However, most non-trivial changes are discussed in advance
            in the <link linkend="mailing">mailing lists</link>, and there
            are no restrictions on who may take part in the
            discussion.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="where-get">
          <para>Where can I get FreeBSD?</para>
        </question>

        <answer>
          <para>Every significant release of FreeBSD is available via
            anonymous FTP from the <ulink
            URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/">
            FreeBSD FTP site</ulink>:</para>

          <itemizedlist>
            <listitem>
              <para>For the current 3.X-STABLE release, 3.5.1-RELEASE, see
                the <ulink
                URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/3.5.1-RELEASE/">3.5.1-RELEASE directory</ulink>.</para>
            </listitem>

            <listitem>
              <para>The current 4-STABLE release, &rel.current;-RELEASE can be
                found in the <ulink
                URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/&rel.current;-RELEASE/">&rel.current;-RELEASE directory</ulink>.</para>
            </listitem>

            <listitem>
              <para><ulink
                URL="ftp://releng4.FreeBSD.org/pub/FreeBSD/">4.X
                snapshots</ulink> are usually made once a day.</para>
            </listitem>

            <listitem>
              <para><ulink
                URL="ftp://current.FreeBSD.org/pub/FreeBSD/">
                5.0 Snapshot</ulink> releases are made once a day for the
                <link linkend="current">-CURRENT</link> branch, these being
                of service purely to bleeding-edge testers and
                developers.</para>
            </listitem>
          </itemizedlist>

	  <para>Information about obtaining FreeBSD on CD, DVD, and other
	    media can be found in <ulink url="../handbook/mirrors.html">the
	      Handbook</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="access-pr">
          <para>How do I access the Problem Report database?</para>
        </question>

        <answer>
          <para>The Problem Report database of all user change requests
            may be queried (or submitted to) by using our web-based PR
            <ulink
            URL="http://www.FreeBSD.org/send-pr.html">submission</ulink>
            and <ulink
            URL="http://www.FreeBSD.org/cgi/query-pr-summary.cgi?query">
            query</ulink>
            interfaces.  The &man.send-pr.1; command can
            also be used to submit problem reports and change requests via
            electronic mail.</para>

	  <para>Before submitting a problem report, please read <ulink
  	    URL="../../articles/problem-reports/article.html">this
  	    article</ulink> on how to write good problem
  	    reports.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="become-web-mirror">
          <para>How do I become a FreeBSD Web mirror?</para>
        </question>

        <answer>
          <para>There are multiple ways to mirror the Web
            pages.</para>

          <itemizedlist>
            <listitem>
              <para>You can retrieve the formatted files from a
                FreeBSD CVSup server using the application
                <filename role="package">net/cvsup</filename>.  The file
                <filename>/usr/share/examples/cvsup/www-supfile</filename>
                contains an example CVSup configuration file for web
                mirrors.
              </para>
            </listitem>

            <listitem>
              <para>You can download the web site source code from any
                FreeBSD FTP server using your favorite ftp mirror
                tool.  Keep in mind that you have to build these
                sources before publishing them.  Start mirroring at
                <ulink
                URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/FreeBSD-current/www">ftp://ftp.FreeBSD.org/pub/FreeBSD/FreeBSD-current/www</ulink>.</para>
            </listitem>
          </itemizedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="other-info-sources">
          <para>What other sources of information are there?</para>
        </question>

        <answer>
          <para>Please check the <ulink
            url="http://www.FreeBSD.org/docs.html">Documentation</ulink>
            list on the main <ulink
            url="http://www.FreeBSD.org">FreeBSD</ulink> web
            site.</para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="support">
    <title>Documentation and Support</title>
    
    <qandaset>
      <qandaentry>
	<question id="books">
	  <para>What good books are there about FreeBSD?</para>
	</question>
	
	<answer>
	  <para>The project produces a wide range of documentation, available
	    from this link: 
	    <ulink url="http://www.freebsd.org/docs.html">http://www.FreeBSD.org/docs.html</ulink>.  
	    
	    In addition, the Bibliography at the end of this FAQ, and the 
	    one in the Handbook reference other recommended books.</para>
	</answer>
      </qandaentry>
      
      <qandaentry>
        <question id="doc-formats">
          <para>Is the documentation available in other formats, such as plain
            text (ASCII), or Postscript?</para>
        </question>

        <answer>
          <para>Yes.  The documentation is available in a number of
            different formats and compression schemes on the FreeBSD
            FTP site, in the <ulink
            URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/">/pub/FreeBSD/doc/</ulink>
            directory.</para>

          <para>The documentation is categorised in a number of different
            ways.  These include:</para>

          <itemizedlist>
            <listitem>
              <para>The document's name, such as <literal>faq</literal>, or
                <literal>handbook</literal>.</para>
            </listitem>

            <listitem>
              <para>The document's language and encoding.  These are based on
                the locale names you will find under
                <filename>/usr/share/locale</filename> on your FreeBSD
                system.  The current languages and encodings that we have for
                documentation are as follows:</para>

              <informaltable frame="none">
                <tgroup cols="2">
                  <thead>
                    <row>
                      <entry>Name</entry>

                      <entry>Meaning</entry>
                    </row>
                  </thead>

                  <tbody>
                    <row>
                      <entry><literal>en_US.ISO8859-1</literal></entry>

                      <entry>US English</entry>
                    </row>

                    <row>
                      <entry><literal>de_DE.ISO8859-1</literal></entry>

                      <entry>German</entry>
                    </row>

                    <row>
                      <entry><literal>es_ES.ISO8859-1</literal></entry>

                      <entry>Spanish</entry>
                    </row>

                    <row>
                      <entry><literal>fr_FR.ISO8859-1</literal></entry>

                      <entry>French</entry>
                    </row>

                    <row>
                      <entry><literal>ja_JP.eucJP</literal></entry>

                      <entry>Japanese (EUC encoding)</entry>
                    </row>

                    <row>
                      <entry><literal>ru_RU.KOI8-R</literal></entry>

                      <entry>Russian (KOI8-R encoding)</entry>
                    </row>

                    <row>
                      <entry><literal>zh_TW.Big5</literal></entry>

                      <entry>Chinese (Big5 encoding)</entry>
                    </row>
                  </tbody>
                </tgroup>
              </informaltable>

              <note>
                <para>Some documents may not be available in all
                  languages.</para>
              </note>
            </listitem>

            <listitem>
              <para>The document's format.  We produce the documentation in a
                number of different output formats to try and make it as
                flexible as possible.  The current formats are;</para>

              <informaltable frame="none">
                <tgroup cols="2">
                  <thead>
                    <row>
                      <entry>Format</entry>

                      <entry>Meaning</entry>
                    </row>
                  </thead>

                  <tbody>
                    <row>
                      <entry><literal>html-split</literal></entry>

                      <entry>A collection of small, linked, HTML
                        files.</entry>
                    </row>

                    <row>
                      <entry><literal>html</literal></entry>

                      <entry>One large HTML file containing the entire
                        document</entry>
                    </row>

                    <row>
                      <entry><literal>pdb</literal></entry>

                      <entry>Palm Pilot database format, for use with the
                        <ulink URL="http://www.iSilo.com/">iSilo</ulink>
                        reader.</entry>
                    </row>

                    <row>
                      <entry><literal>pdf</literal></entry>

                      <entry>Adobe's Portable Document Format</entry>
                    </row>

                    <row>
                      <entry><literal>ps</literal></entry>

                      <entry>Postscript</entry>
                    </row>

                    <row>
                      <entry><literal>rtf</literal></entry>

                      <entry>Microsoft's Rich Text Format<footnote>
                          <para>Page numbers are not automatically updated
                            when loading this format in to Word.  Press
                            <keycombo action="simul"><keycap>CTRL</keycap><keycap>A</keycap></keycombo>,
                            <keycombo action="simul"><keycap>CTRL</keycap><keycap>END</keycap></keycombo>,
                            <keycap>F9</keycap> after loading the document, to
                            update the page numbers.</para>
                        </footnote>
                      </entry>
                    </row>

                    <row>
                      <entry><literal>txt</literal></entry>

                      <entry>Plain text</entry>
                    </row>
                  </tbody>
                </tgroup>
              </informaltable>
            </listitem>

            <listitem>
              <para>The compression and packaging scheme.  There are three of
                these currently in use.</para>

              <orderedlist>
                <listitem>
                  <para>Where the format is <literal>html-split</literal>, the
                    files are bundled up using &man.tar.1;.  The resulting
                    <filename>.tar</filename> file is then compressed using
                    the compression schemes detailed in the next point.</para>
                </listitem>

                <listitem>
                  <para>All the other formats generate one file, called
                    <filename>book.<replaceable>format</replaceable></filename>
                    (i.e., <filename>book.pdb</filename>,
                    <filename>book.html</filename>, and so on).</para>

                  <para>These files are then compressed using three
                    compression schemes.</para>

                  <informaltable frame="none">
                    <tgroup cols="2">
                      <thead>
                        <row>
                          <entry>Scheme</entry>

                          <entry>Description</entry>
                        </row>
                      </thead>

                      <tbody>
                        <row>
                          <entry><literal>zip</literal></entry>

                          <entry>The Zip format.  If you want to uncompress
                            this on FreeBSD you will need to install the
                            <filename role="package">archivers/unzip</filename> port
                            first.</entry>
                        </row>

                        <row>
                          <entry><literal>gz</literal></entry>

                          <entry>The GNU Zip format.  Use &man.gunzip.1; to
                            uncompress these files, which is part of
                            FreeBSD.</entry>
                        </row>

                        <row>
                          <entry><literal>bz2</literal></entry>

                          <entry>The BZip2 format.  Less widespread than the
                            others, but generally gives smaller files.
                            Install the <filename role="package">archivers/bzip2</filename>
                            port to uncompress these files.</entry>
                        </row>
                      </tbody>
                    </tgroup>
                  </informaltable>

                  <para>So the Postscript version of the Handbook, compressed
                    using BZip2 will be stored in a file called
                    <filename>book.ps.bz2</filename> in the
                    <filename>handbook/</filename> directory.</para>
                </listitem>

                <listitem>
                  <para>The formatted documentation is also available as a
                    FreeBSD package, of which more later.</para>
                </listitem>
              </orderedlist>
            </listitem>
          </itemizedlist>

          <para>After choosing the format and compression mechanism that you
            want to download, you must then decide whether or not you want to
            download the document as a FreeBSD
            <emphasis>package</emphasis>.</para>

          <para>The advantage of downloading and installing the package is
            that the documentation can then be managed using the normal
            FreeBSD package management comments, such as &man.pkg.add.1; and
            &man.pkg.delete.1;.</para>

          <para>If you decide to download and install the package then you
            must know the filename to download.  The documentation-as-packages
            files are stored in a directory called
            <filename>packages</filename>.  Each package file looks like
            <filename><replaceable>document-name</replaceable>.<replaceable>lang</replaceable>.<replaceable>encoding</replaceable>.<replaceable>format</replaceable>.tgz</filename>.</para>

          <para>For example, the FAQ, in English, formatted as PDF, is in the
            package called
            <filename>faq.en_US.ISO8859-1.pdf.tgz</filename>.</para>

          <para>Knowing this, you can use the following command to install the
            English PDF FAQ package.</para>

          <screen>&prompt.root; <userinput>pkg_add ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/packages/faq.en_US.ISO8859-1.pdf.tgz</userinput></screen>

          <para>Having done that, you can use &man.pkg.info.1; to determine
            where the file has been installed.</para>

          <screen>&prompt.root; <userinput>pkg_info -f faq.en_US.ISO8859-1.pdf</userinput>
Information for faq.en_US.ISO8859-1.pdf:

Packing list:
        Package name: faq.en_US.ISO8859-1.pdf
        CWD to /usr/share/doc/en_US.ISO8859-1/books/faq
File: book.pdf
        CWD to .
File: +COMMENT (ignored)
File: +DESC (ignored)</screen>

          <para>As you can see, <filename>book.pdf</filename> will have been
            installed in to
            <filename>/usr/share/doc/en_US.ISO8859-1/books/faq</filename>.
          </para>

          <para>If you do not want to use the packages then you will have to
            download the compressed files yourself, uncompress them, and then
            copy the appropriate documents in to place.</para>

          <para>For example, the split HTML version of the FAQ, compressed
            using &man.gzip.1;, can be found in the
            <filename>doc/en_US.ISO8859-1/books/faq/book.html-split.tar.gz</filename>
            file.  To download and uncompress that file you would have to do
            this.</para>

          <screen>&prompt.root; <userinput>fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/en_US.ISO8859-1/books/faq/book.html-split.tar.gz</userinput>
&prompt.root; <userinput>gzip -d book.html-split.tar.gz</userinput>
&prompt.root; <userinput>tar xvf book.html-split.tar</userinput></screen>

          <para>You will be left with a collection of
            <filename>.html</filename> files.  The main one is called
            <filename>index.html</filename>, which will contain the table of
            contents, introductory material, and links to the other parts of
            the document.  You can then copy or move these to their final
            location as necessary.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="mailing">
          <para>Where do I find info on the FreeBSD mailing lists?</para>
        </question>

        <answer>
          <para>You can find full information in the <ulink
            URL="../handbook/eresources.html#ERESOURCES-MAIL">Handbook
            entry on mailing-lists</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="y2k">
          <para>Where do I find the FreeBSD Y2K info?</para>
        </question>

        <answer>
          <para>You can find full information in the <ulink
            URL="../../../../y2kbug.html">FreeBSD Y2K
            page</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="newsgroups">
          <para>What FreeBSD news groups are available?</para>
        </question>

        <answer>
          <para>You can find full information in the <ulink
            URL="../handbook/eresources-news.html">Handbook entry on
            newsgroups</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="irc">
          <para>Are there FreeBSD IRC (Internet Relay Chat)
            channels?</para>
        </question>

        <answer>
          <para>Yes, most major IRC networks host a FreeBSD chat
            channel:</para>

          <itemizedlist>
            <listitem>
              <para>Channel <literal>#FreeBSD</literal> on
                <ulink URL="http://www.efnet.org/index.php">EFNet</ulink>
                is a FreeBSD forum, but do not go there for tech
                support or to try and get folks there to help you avoid
                the pain of reading man pages or doing your own research.
                It is a chat channel, first and foremost, and topics there
                are just as likely to involve sex, sports or nuclear
                weapons as they are FreeBSD.  You Have Been Warned!
                Available at server <hostid>irc.chat.org</hostid>.</para>
            </listitem>

            <listitem>
              <para>Channel <literal>#FreeBSDhelp</literal> on
                <ulink URL="http://www.efnet.org/index.php">EFNet</ulink>
                is a channel dedicated to helping FreeBSD users. They
                are much more sympathetic to questions then
                <literal>#FreeBSD</literal> is.</para>
            </listitem>

            <listitem>
              <para>Channel <literal>#FreeBSD</literal> on
                <ulink URL="http://www.dal.net/">DALNET</ulink>
                is available at <hostid>irc.dal.net</hostid> in the
                US and  <hostid>irc.eu.dal.net</hostid> in Europe.</para>
            </listitem>

            <listitem>
              <para>Channel <literal>#FreeBSD</literal> on
                <ulink URL="http://www.undernet.org/">UNDERNET</ulink>
                is available at <hostid>us.undernet.org</hostid>
                in the US and  <hostid>eu.undernet.org</hostid> in Europe.
                Since it is a help channel, be prepared to read the
                documents you are referred to.</para>
            </listitem>

            <listitem>
              <para>Channel <literal>#FreeBSD</literal> on <ulink
                url="http://www.hybnet.net/">HybNet</ulink>.  This channel
                <emphasis>is</emphasis> a help channel.  A list of servers
                can be found on the <ulink
                url="http://www.hybnet.net/">HybNet web site</ulink>.</para>
            </listitem>
          </itemizedlist>

          <para>Each of these channels are distinct and are not
            connected to each other.  Their chat styles also differ,
            so you may need to try each to find one suited to your
            chat style.  As with <emphasis>all</emphasis> types of IRC
            traffic, if you are easily offended or cannot deal with
            lots of young people (and more than a few older ones)
            doing the verbal equivalent of jello wrestling, do not
            even bother with it.</para>
        </answer>
      </qandaentry>

      <qandaentry>
	<question id="training">
	  <para>Where can I get commercial FreeBSD training and support?</para>
	</question>

	<answer>
	  <para>DaemonNews provides commercial training and support for
	    FreeBSD.  More information can be found at their 
	    <ulink url="http://www.bsdmall.com/">BSD Mall</ulink> 
	    site.</para>

          <para>The FreeBSD Mall provides commercial FreeBSD support.
            You can get more information at their <ulink
            url="http://www.freebsdmall.com/">web site</ulink>.</para>

	  <para>Any other organisations providing training and support should
	    contact the project in order to be listed here.</para>
	</answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter
    id="install">
    <chapterinfo>
      <author>
	<firstname>Nik</firstname>
	<surname>Clayton</surname>
	<affiliation>
	  <address><email>nik@FreeBSD.org</email></address>
	</affiliation>
      </author>
    </chapterinfo>
    
    <title>Installation</title>

    <qandaset>
      <qandaentry>
        <question id="floppy-download">
          <para>Which file do I download to get FreeBSD?</para>
        </question>

        <answer>
          <para>Prior to release 3.1, you only needed one floppy image to
            install FreeBSD, namely <filename>floppies/boot.flp</filename>.
            However, since release 3.1 the Project has added out-of-the-box
            support for a wide variety of hardware, which takes up more
            space.  For 3.x and later you need two floppy images:
            <filename>floppies/kernel.flp</filename> and
            <filename>floppies/mfsroot.flp</filename>. These images need to
            be copied onto floppies by tools like
            <command>fdimage</command> or &man.dd.1;.</para>

          <para>If you need to download the distributions yourself (for a
            DOS filesystem install, for instance), below are some
            recommendations for distributions to grab:</para>


          <itemizedlist>
            <listitem>
              <para>bin/</para>
            </listitem>

            <listitem>
              <para>manpages/</para>
            </listitem>

            <listitem>
              <para>compat*/</para>
            </listitem>

            <listitem>
              <para>doc/</para>
            </listitem>

            <listitem>
              <para>src/ssys.*</para>
            </listitem>
          </itemizedlist>


          <para>Full instructions on this procedure and a little bit more
            about installation issues in general can be found in the
            <ulink URL="../handbook/install.html">Handbook entry on
            installing FreeBSD</ulink>.</para>

        </answer>
      </qandaentry>

      <qandaentry>
        <question id="floppy-image-too-large">
          <para>What do I do if the floppy images does not fit on a single
            floppy?</para>
        </question>

        <answer>
          <para>A 3.5 inch (1.44MB) floppy can accommodate 1474560 bytes
            of data. The boot image is exactly 1474560 bytes in size.</para>

          <para>Common mistakes when preparing the boot floppy are:</para>

          <itemizedlist>
            <listitem>
              <para>Not downloading the floppy image in
                <emphasis>binary</emphasis> mode when using
                <acronym>FTP</acronym>.</para>


              <para>Some FTP clients default their transfer mode to
                <emphasis>ascii</emphasis> and attempt to change any
                end-of-line characters received to match the conventions
                used by the client's system. This will almost invariably
                corrupt the boot image. Check the size of the downloaded
                boot image: if it is not <emphasis>exactly</emphasis> that
                on the server, then the download process is suspect.</para>

              <para>To workaround: type <emphasis>binary</emphasis> at the
                FTP command prompt after getting connected to the server
                and before starting the download of the image.</para>
            </listitem>

            <listitem>
              <para>Using the DOS <command>copy</command> command (or
                equivalent GUI tool) to transfer the boot image to
                floppy.</para>

              <para>Programs like <command>copy</command> will not work as
                the boot image has been created to be booted into directly.
                The image has the complete content of the floppy, track for
                track, and is not meant to be placed on the floppy as a
                regular file. You have to transfer it to the floppy
                <quote>raw</quote>, using the low-level tools (e.g.
                <command>fdimage</command> or <command>rawrite</command>)
                described in the <ulink
                URL="../handbook/install.html">installation guide to
                FreeBSD</ulink>.</para>
            </listitem>
          </itemizedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="install-instructions-location">
          <para>Where are the instructions for installing FreeBSD?</para>
        </question>

        <answer>
          <para>Installation instructions can be found in the
            <ulink URL="../handbook/install.html">Handbook entry on installing FreeBSD</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="need-to-run">
          <para>What do I need in order to run FreeBSD?</para>
        </question>

        <answer>
          <para>You will need a 386 or better PC, with 5 MB or more of RAM
            and at least 60 MB of hard disk space. It can run with a low
            end MDA graphics card but to run X11R6, a VGA or better video
            card is needed.</para>

          <para>See also 
            <xref linkend="hardware"></para>

        </answer>
      </qandaentry>

      <qandaentry>
        <question id="four-meg-ram-install">
          <para>I have only 4 MB of RAM. Can I install FreeBSD?</para>
        </question>

        <answer>
          <para>FreeBSD 2.1.7 was the last version of FreeBSD that
            could be installed on a 4MB system.  FreeBSD 2.2 and later
            needs at least 5MB to install on a new system.</para>

          <para>All versions of FreeBSD will <emphasis>run</emphasis>
            in 4MB of RAM, they just cannot run the installation
            program in 4MB. You can add extra memory for the install
            process, if you like, and then after the system is up and
            running, go back to 4MB. Or you could swap your disk into
            a system which has &gt;4MB, install onto the disk and then
            swap it back.</para>

          <para>FreeBSD 2.1.7 will not install with 640 kB base + 3 MB
            extended memory. If your motherboard can remap some of the
            <quote>lost</quote> memory out of the 640kB to 1MB region,
            then you may still be able to get FreeBSD 2.1.7 up.  Try
            to go into your BIOS setup and look for a
            <quote>remap</quote> option.  Enable it.  You may also
            have to disable ROM shadowing.  It may be easier to get 4
            more MB just for the install.  Build a custom kernel with
            only the options you need and then remove the 4MB out.
            You can also install 2.0.5 and then upgrade your system to
            2.1.7 with the <quote>upgrade</quote> option of the 2.1.7
            installation program.</para>

          <para>After the installation, if you build a custom kernel,
            it will run in 4 MB. Someone has even successfully booted
            with 2 MB, although the system was almost unusable.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="custom-boot-floppy">
          <para>How can I make my own custom install floppy?</para>
        </question>

        <answer>
          <para>Currently there is no way to <emphasis>just</emphasis>
            make a custom install floppy. You have to cut a whole new
            release, which will include your install floppy.</para>

          <para>To make a custom release, follow the instructions in the
            <ulink url="../../articles/releng/article.html">Release
            Engineering</ulink> article.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="multiboot">
          <para>Can I have more than one operating system on my PC?</para>
        </question>

        <answer>
          <para>Have a look at
            <ulink URL="../../articles/multi-os/index.html">
            the multi-OS page</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="windows-coexist">
          <para>Can Windows 95/98 co-exist with FreeBSD?</para>
        </question>

        <answer>
          <para>Install Windows 95/98 first, after that FreeBSD.
            FreeBSD's boot manager will then manage to boot Win95/98 and
            FreeBSD. If you install Windows 95/98 second, it will boorishly
            overwrite your boot manager without even asking. If that
            happens, see the next section.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="win95-damaged-boot-manager">
          <para>Windows 95/98 killed my boot manager!
            How do I get it back?</para>
        </question>

        <answer>
          <para>You can reinstall the boot manager FreeBSD comes with in
            one of three ways:</para>

          <itemizedlist>
            <listitem>
              <para>Running DOS, go into the tools/ directory of your
                FreeBSD distribution and look for
                <filename>bootinst.exe</filename>.  You run it like
                so:</para>

              <screen><prompt>...\TOOLS&gt;</prompt> <userinput>bootinst.exe boot.bin</userinput></screen>

              <para>and the boot manager will be reinstalled.</para>
            </listitem>

            <listitem>
              <para>Boot the FreeBSD boot floppy again and go to the
                Custom installation menu item. Choose Partition. Select the
                 drive which used to contain your boot manager (likely the
                 first one) and when you come to the partition editor for
                 it, as the very first thing (e.g. do not make any changes)
                 select (W)rite. This will ask for confirmation, say yes,
                 and when you get the Boot Manager selection prompt, be
                 sure to select <quote>Boot Manager</quote>. This will
                 re-write the boot manager to disk. Now quit out of the
                 installation menu and reboot off the hard disk as
                 normal.</para>
            </listitem>

            <listitem>
              <para>Boot the FreeBSD boot floppy (or CDROM) and choose the
                <quote>Fixit</quote> menu item. Select either the Fixit
                floppy or CDROM #2 (the <quote>live</quote> file system
                option) as appropriate and enter the fixit shell. Then
                execute the following command:</para>

              <screen><prompt>Fixit#</prompt> <userinput>fdisk -B -b /boot/boot0 <replaceable>bootdevice</replaceable></userinput></screen>

              <para>substituting <replaceable>bootdevice</replaceable> for
                your real
                boot device such as <devicename>ad0</devicename> (first IDE
                disk), <devicename>ad4</devicename> (first IDE disk on
                auxiliary controller), <devicename>da0</devicename> (first
                SCSI disk), etc.</para>
            </listitem>
          </itemizedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="boot-on-thinkpad">
          <para>My A, T, or X series IBM Thinkpad locks up when I first
            booted up my FreeBSD installation.  How can I solve this?</para>
        </question>

        <answer>
          <para>A bug in early revisions of IBM's BIOS on these machines
            mistakenly identifies the FreeBSD partition as a potential FAT
            suspend-to-disk partition.  When the BIOS tries to parse the
            FreeBSD partition it hangs.</para>

          <para>According to IBM<footnote><para>In an e-mail from Keith
                Frechette
                <email>kfrechet@us.ibm.com</email>.</para></footnote>, the
            following model/BIOS release numbers incorporate the fix.</para>

          <informaltable frame="none">
            <tgroup cols="2">
              <thead>
                <row>
                  <entry>Model</entry>
                  <entry>BIOS revision</entry>
                </row>
              </thead>

              <tbody>
                <row>
                  <entry>T20</entry>
                  <entry>IYET49WW or later</entry>
                </row>

                <row>
                  <entry>T21</entry>
                  <entry>KZET22WW or later</entry>
                </row>

                <row>
                  <entry>A20p</entry>
                  <entry>IVET62WW or later</entry>
                </row>

                <row>
                  <entry>A20m</entry>
                  <entry>IWET54WW or later</entry>
                </row>

                <row>
                  <entry>A21p</entry>
                  <entry>KYET27WW or later</entry>
                </row>

                <row>
                  <entry>A21m</entry>
                  <entry>KXET24WW or later</entry>
                </row>

                <row>
                  <entry>A21e</entry>
                  <entry>KUET30WW</entry>
                </row>
              </tbody>
            </tgroup>
          </informaltable>

	  <para>It has been reported that later IBM BIOS revisions may have
	    reintroduced the bug.  <ulink
					  url="http://www.FreeBSD.org/cgi/getmsg.cgi?fetch=200565+208320+/usr/local/www/db/text/2001/freebsd-mobile/20010429.freebsd-mobile">This message</ulink>
	    from Jacques Vidrine to the &a.mobile; describes a procedure
            which may work if your newer IBM laptop does not boot FreeBSD
            properly, and you can upgrade or downgrade the BIOS..</para>
	
          <para>If you have an earlier BIOS, and upgrading is not an option a
            workaround is to install FreeBSD, change the partition ID FreeBSD
            uses, and install new boot blocks that can handle the different
            partition ID.</para>

          <para>First, you will need to restore the machine to a state where
            it can get through its self-test screen.  Doing this requires
            powering up the machine without letting it find a FreeBSD
            partition on its primary disk.  One way is to remove the hard disk
            and temporarily move it to an older ThinkPad (such as a ThinkPad
            600) or a desktop PC with an appropriate conversion cable.  Once
            it is there, you can delete the FreeBSD partition and move the hard
            disk back.  The ThinkPad should now be in a bootable state
            again.</para>

          <para>With the machine functional again, you can use the workaround
            procedure described here to get a working FreeBSD
            installation.</para>

          <procedure>
            <step>
              <para>Download <filename>boot1</filename> and
                <filename>boot2</filename> from <ulink
                  url="http://people.FreeBSD.org/~bmah/ThinkPad/">http://people.FreeBSD.org/~bmah/ThinkPad/</ulink>.
                Put these files somewhere you will be able to retrieve them
                later.</para>
            </step>

            <step>
              <para>Install FreeBSD as normal on to the ThinkPad.
                <emphasis>Do not</emphasis> use <literal>Dangerously
                  Dedicated</literal> mode.  <emphasis>Do not</emphasis>
                reboot when the install has finished.</para>
            </step>

            <step>
              <para>Either switch to the <quote>Emergency Holographic
                  Shell</quote> (<keycombo action="simul"><keycap>ALT</keycap>
                  <keycap>F4</keycap></keycombo>) or start a
                <quote>fixit</quote> shell.</para>
            </step>

            <step>
              <para>Use &man.fdisk.8; to change the FreeBSD partition ID from
                <literal>165</literal> to <literal>166</literal> (this is the
                  type used by OpenBSD).</para>
            </step>

            <step>
              <para>Bring the <filename>boot1</filename> and
                <filename>boot2</filename> files to the local
                filesystem.</para>
            </step>

            <step>
              <para>Use &man.disklabel.8; to write <filename>boot1</filename>
                and <filename>boot2</filename> to your FreeBSD slice.</para>

              <screen>&prompt.root; <userinput>disklabel -B -b boot1 -s boot2 ad0s<replaceable>n</replaceable></userinput></screen>

              <para><replaceable>n</replaceable> is the number of the slice
                where you installed FreeBSD.</para>
            </step>

            <step>
              <para>Reboot.  At the boot prompt you will be given the option
                of booting <literal>OpenBSD</literal>.  This will actually
                boot FreeBSD.</para>
            </step>
          </procedure>

          <para>Getting this to work in the case where you want to dual boot
          OpenBSD and FreeBSD on the same laptop is left as an exercise for
          the reader.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="install-bad-blocks">
          <para>Can I install on a disk with bad blocks?</para>
        </question>

        <answer>
          <para>Prior to 3.0, FreeBSD included a utility known as
            <command>bad144</command>, which automatically remapped bad
            blocks. Because modern IDE drives perform this function
            themselves, <command>bad144</command> has been removed from the
            FreeBSD source tree. If you wish to install FreeBSD 3.0 or
            later, we strongly suggest you purchase a newer disk drive. If
            you do not wish to do this, you must run FreeBSD 2.x.</para>
            <para>If you are seeing bad block errors with a modern IDE
            drive, chances are the drive is going to die very soon (the
            drive's internal remapping functions are no longer sufficient
            to fix the bad blocks, which means the disk is heavily
            corrupted); we suggest you buy a new hard drive.</para>

          <para>If you have a SCSI drive with bad blocks, see
            <link linkend="awre">this answer</link>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="bad144-3x-4x">
          <para>I have just upgraded from 3.X to 4.X, and my first boot
            failed with <errorname>bad sector table not
            supported</errorname></para>
        </question>

        <answer>
          <para>FreeBSD 3.X and earlier supported
            <command>bad144</command>, which automatically remapped
            bad blocks.  FreeBSD 4.X and later do not support this, as
            modern IDE drives include this functionality.  See <link
            linkend="install-bad-blocks">this question</link> for
            more information.</para>

          <para>To fix this after an upgrade, you need to physically
            place the drive in a working system and use
            &man.disklabel.8; as discussed in the following
            questions.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="find-bad144">
          <para>How do I tell if a drive has <command>bad144</command>
            information on it before I try to upgrade to FreeBSD 4.0
            and it fails?</para>
        </question>

        <answer>
          <para>Use &man.disklabel.8; for this.  <command>disklabel -r
            <replaceable>drive device</replaceable></command> will
            give you the contents of your disk label.  Look for a
            <literal>flags</literal> field.  If you see
            <literal>flags: badsect</literal>, this drive is using
            bad144.  For example, the following drive has
            <command>bad144</command> enabled.:</para>

          <screen>&prompt.root; disklabel -r wd0
# /dev/rwd0c:
type: ESDI
disk: wd0s1
label:
flags: badsect
bytes/sector: 512
sectors/track: 63</screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="disable-bad144">
          <para>How do I remove <command>bad144</command> from my
            pre-4.X system so I can upgrade safely?</para>
        </question>

        <answer>
          <para>Use <command>disklabel -e -rwd0 </command> to edit the
            disklabel in place.  Just remove the word
            <literal>badsect</literal> from the flags field, save, and
            exit.  The bad144 file will still take up some space on
            your drive, but the disk itself will be usable.</para>

          <para>We still recommend you purchase a new disk if you have
            a large number of bad blocks.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="boot-floppy-strangeness">
          <para>Strange things happen when I boot the install floppy!
            What is happening?</para>
        </question>

        <answer>
          <para>If you are seeing things like the machine grinding to a halt
            or spontaneously rebooting when you try to boot the install
            floppy, here are three questions to ask yourself:-</para>

          <orderedlist>
            <listitem>
              <para>Did you use a new, freshly-formatted, error-free floppy
                (preferably a brand-new one straight out of the box, as
                opposed to the magazine cover disk that has been lying under
                the bed for the last three years)?</para>
            </listitem>

            <listitem>
              <para>Did you download the floppy image in binary (or image)
                mode? (do not be embarrassed, even the best of us have
                accidentally downloaded a binary file in ASCII mode at
                least once!)</para>
            </listitem>

            <listitem>
              <para>If you are using Windows95 or Win98 did you run
                <command>fdimage</command> or <command>rawrite</command> in
                pure DOS mode? These operating systems can interfere with programs that
                write directly to hardware, which the disk creation program
                does; even running it inside a DOS shell in the GUI can
                cause this problem.</para>
            </listitem>
          </orderedlist>

          <para>There have also been reports of Netscape causing problems
            when downloading the boot floppy, so it is probably best to use
            a different FTP client if you can.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="no-install-cdrom">
          <para>I booted from my ATAPI CDROM, but the install program says no
            CDROM is found.  Where did it go?</para>
        </question>

        <answer>
          <para>The usual cause of this problem is a mis-configured CDROM
            drive.  Many PCs now ship with the CDROM as the slave device on
            the secondary IDE controller, with no master device on that
            controller.  This is illegal according to the ATAPI specification,
            but Windows plays fast and loose with the specification, and the
            BIOS ignores it when booting.  This is why the BIOS was able to
            see the  CDROM to boot from it, but why FreeBSD cannot see it to
            complete  the install.</para>

          <para>Reconfigure your system so that the CDROM is either the
            master device on the IDE controller it is attached to, or make
            sure that it is the slave on an IDE controller that also has a
            master device.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="cannot-install-tape">
          <para>Why can I not install from tape?</para>
        </question>

        <answer>
          <para>If you are installing 2.1.7R from tape, you  must create
            the tape using a tar blocksize of 10 (5120 bytes). The default
            tar blocksize is 20 (10240 bytes), and tapes created using this
            default size cannot be used to install 2.1.7R; with these
            tapes, you will get an error that complains about the record
            size being too big.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="install-PLIP">
          <para>Can I install on my laptop over PLIP (Parallel Line
            IP)?</para>
        </question>

        <answer>
          <para>Yes. Use a standard Laplink cable. If necessary, you
            can check out the <ulink url="../handbook/plip.html">PLIP
            section of the Handbook</ulink> for details on parallel
            port networking.</para>

          <para>If you are running FreeBSD 3.X or earlier, also look at
            the <ulink
            url="http://www.FreeBSD.org/docs.html#PAO">Mobile
            Computing page</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="geometry">
          <para>Which geometry should I use for a disk drive?</para>
        </question>

        <answer>
            <note>
              <para>By the <quote>geometry</quote> of a disk, we mean
              the number of cylinders, heads and sectors/track on a
              disk.  We will refer to this as C/H/S for
              convenience. This is how the PC's BIOS works out which
              area on a disk to read/write from.</para>
            </note>

          <para>This causes a lot of confusion among new system
            administrators.  First of all, the
            <emphasis>physical</emphasis> geometry of a SCSI drive is
            totally irrelevant, as FreeBSD works in term of disk
            blocks. In fact, there is no such thing as
            <quote>the</quote> physical geometry, as the sector
            density varies across the disk.  What manufacturers claim
            is the <quote>physical geometry</quote> is usually the
            geometry that they have determined wastes the least
            space. For IDE disks, FreeBSD does work in terms of C/H/S,
            but all modern drives internally convert this into block
            references.
            </para>

          <para>All that matters is the <emphasis>logical</emphasis>
            geometry.  This is the answer that the BIOS gets when it
            asks the drive <quote>what is your geometry?</quote> It
            then uses this geometry to access the disk. As FreeBSD
            uses the BIOS when booting, it is very important to get
            this right. In particular, if you have more than one
            operating system on a disk, they must all agree on the
            geometry.  Otherwise you will have serious problems
            booting!</para>

          <para>For SCSI disks, the geometry to use depends on whether
           extended translation support is turned on in your
           controller (this is often referred to as <quote>support for
           DOS disks &gt;1GB</quote> or something similar). If it is
           turned off, then use <replaceable>N</replaceable>
           cylinders, 64 heads and 32 sectors/track, where
           <replaceable>N</replaceable> is the capacity of the disk in
           MB. For example, a 2GB disk should pretend to have 2048
           cylinders, 64 heads and 32 sectors/track.</para>

          <para>If it <emphasis>is</emphasis> turned on (it is often
            supplied this way to get around certain limitations in
            MSDOS) and the disk capacity is more than 1GB, use M
            cylinders, 63 sectors per track (<emphasis>not</emphasis>
            64), and 255 heads, where 'M' is the disk capacity in MB
            divided by 7.844238 (!). So our example 2GB drive would
            have 261 cylinders, 63 sectors per track and 255
            heads.</para>

          <para>If you are not sure about this, or FreeBSD fails to
            detect the geometry correctly during installation, the
            simplest way around this is usually to create a small DOS
            partition on the disk. The BIOS should then detect the
            correct geometry, and you can always remove the DOS
            partition in the partition editor if you do not want to
            keep it.  You might want to leave it around for
            programming network cards and the like, however.</para>

          <para>Alternatively, there is a freely available utility
            distributed with FreeBSD called
            <filename>pfdisk.exe</filename>.  You can find it in the
            <filename>tools</filename> subdirectory on the FreeBSD
            CDROM or on the various FreeBSD FTP sites.  This program
            can be used to work out what geometry the other operating
            systems on the disk are using. You can then enter this
            geometry in the partition editor.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="disk-divide-restrictions">
          <para>Are there any restrictions on how I divide the disk up?</para>
        </question>

        <answer>
          <para>Yes. You must make sure that your root partition is below
            1024
            cylinders so the BIOS can boot the kernel from it.  (Note that
            this is a limitation in the PC's BIOS, not FreeBSD).</para>

          <para>For a SCSI drive, this will normally imply that the root
            partition will be in the first 1024MB (or in the first 4096MB
            if extended translation is turned on - see previous question).
            For IDE, the corresponding figure is 504MB.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="disk-manager">
          <para>Is FreeBSD compatible with any disk managers?</para>
        </question>

        <answer>
          <para>FreeBSD recognizes the Ontrack Disk Manager and makes
            allowances for it. Other disk managers are not supported.</para>

          <para>If you just want to use the disk with FreeBSD you do not
            need a disk manager. Just configure the disk for as much space
            as the BIOS can deal with (usually 504 megabytes), and FreeBSD
            should figure out how much space you really have. If you are
            using an old disk with an MFM controller, you may need to
            explicitly tell FreeBSD how many cylinders to use.</para>

          <para>If you want to use the disk with FreeBSD and another
            operating system, you may be able to do without a disk manager:
            just make sure the FreeBSD boot partition and the slice for
            the other operating system are in the first 1024 cylinders. If
            you are reasonably careful, a 20 megabyte boot partition should
            be plenty.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="missing-os">
          <para>When I boot FreeBSD I get <errorname>Missing Operating
            System</errorname>.  What is happening?</para>
        </question>

        <answer>
          <para>This is classically a case of FreeBSD and DOS or some other
            OS conflicting over their ideas of disk <link
            linkend="geometry">geometry</link>. You will have to reinstall
            FreeBSD, but obeying the instructions given above will almost
            always get you going.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="stop-at-boot-manager">
          <para>Why can I not get past the boot manager's <prompt>F?</prompt>
            prompt?</para>
        </question>

        <answer>
          <para>This is another symptom of the problem described in the
            preceding question. Your BIOS geometry and FreeBSD geometry
            settings do not agree! If your controller or BIOS supports
            cylinder translation (often marked as <quote>&gt;1GB drive
            support</quote>), try toggling its setting and reinstalling
            FreeBSD.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="need-complete-sources">
          <para>Do I need to install the complete sources?</para>
        </question>

        <answer>
          <para>In general, no.  However, we would strongly recommend that
            you install, at a minimum, the <literal>base</literal> source
            kit, which includes several of the files mentioned here, and
            the <literal>sys</literal> (kernel) source kit, which includes
            sources for the kernel. There is nothing in the system which
            requires the presence of the sources to operate, however,
            except for the kernel-configuration program &man.config.8;.
            With the exception of the kernel sources, our build structure
            is set up so that you can read-only mount the sources from
            elsewhere via NFS and still be able to make new binaries.
            (Because of the kernel-source restriction, we recommend that
            you not mount this on <filename>/usr/src</filename> directly,
            but rather in some other location with appropriate symbolic
            links to duplicate the top-level structure of the source
            tree.)</para>

          <para>Having the sources on-line and knowing how to build a
            system with them will make it much easier for you to upgrade
            to future releases of FreeBSD.</para>

          <para>To actually select a subset of the sources, use the Custom
            menu item when you are in the Distributions menu of the
            system installation tool.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="need-kernel">
          <para>Do I need to build a kernel?</para>
        </question>

        <answer>
          <para>Building a new kernel was originally pretty much a required
            step in a FreeBSD installation, but more recent releases have
            benefited from the introduction of a much friendlier kernel
            configuration tool. When at the FreeBSD boot prompt (boot:),
            use the <option>-c</option> flag and you will be dropped into a
            visual configuration screen which allows you to configure the
            kernel's settings for most common ISA cards.</para>

          <para>It is still recommended that you eventually build a new
            kernel containing just the drivers that you need, just to save a
            bit of RAM, but it is no longer a strict requirement for most
            systems.</para>

        </answer>
      </qandaentry>

      <qandaentry>
        <question id="password-encryption">
          <para>Should I use DES passwords, or MD5, and how do I specify
            which form my users receive?</para>
        </question>

        <answer>
          <para>The default password format on FreeBSD is to use
            <emphasis>MD5</emphasis>-based passwords. These are believed to
            be more secure than the traditional Unix password format, which
            used a scheme based on the <emphasis>DES</emphasis> algorithm.
            DES passwords are still available if you need to share your
            password file with legacy operating systems which still use the
            less secure password format (they are available if you choose
            to install the <quote>crypto</quote> distribution in
            sysinstall, or by installing the crypto sources if building
            from source). Which password format to use for new passwords is
            controlled by the <quote>passwd_format</quote> login capability
            in <filename>/etc/login.conf</filename>, which takes values of
            either <quote>des</quote> (if available) or <quote>md5</quote>.
            See the &man.login.conf.5; manpage for more information about login
            capabilities.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="boot-floppy-hangs">
          <para>Why does the boot floppy start, but hang at the
            <literal>Probing Devices...</literal> screen?</para>
        </question>

        <answer>

          <para>If you have a IDE Zip or Jaz drive installed, remove it
            and try again. The boot floppy can get confused by the drives.
            After the system is installed you can reconnect the drive.
            Hopefully this will be fixed in a later release.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="panic-on-install-reboot">
          <para>Why do I get a <errorname>panic: can't mount root</errorname>
            error when rebooting the system after installation?</para>
        </question>

        <answer>
          <para>This error comes from confusion between the boot block's
            and the kernel's understanding of the disk devices. The error
            usually manifests on two-disk IDE systems, with the hard disks
            arranged as the master or single device on separate IDE
            controllers, with FreeBSD installed on the secondary IDE
            controller. The boot blocks think the system is installed on
            wd1 (the second BIOS disk) while the kernel assigns the first
            disk on the secondary controller device wd2. After the device
            probing, the kernel tries to mount what the boot blocks think
            is the boot disk, wd1, while it is really wd2, and
            fails.</para>

          <para>To fix the problem, do one of the following:</para>

            <orderedlist>
              <listitem>
                <para>For FreeBSD 3.3 and later, reboot the system and hit
                  <literal>Enter</literal> at the <literal>Booting kernel
                  in 10 seconds; hit [Enter] to interrupt</literal> prompt.
                  This will drop you into the boot loader.</para>

                <para>Then type
                  <literal>
                  set root_disk_unit="<replaceable>disk_number</replaceable>"
                  </literal>. <replaceable>disk_number</replaceable>
                  will be <literal>0</literal> if FreeBSD is installed on
                  the master drive on the first IDE controller,
                  <literal>1</literal> if it is installed on the slave on
                  the first IDE controller, <literal>2</literal> if it is
                  installed on the master of the second IDE controller, and
                  <literal>3</literal> if it is installed on the slave of
                  the second IDE controller.</para>

                <para>Then type <literal>boot</literal>, and your system
                  should boot correctly.</para>

                <para>To make this change permanent (ie so you do not have to
                  do this every time you reboot or turn on your FreeBSD
                  machine), put the line <literal>
                  root_disk_unit="<replaceable>disk_number</replaceable>"</literal> in <filename>/boot/loader.conf.local
                  </filename>.</para>
              </listitem>

              <listitem>
                <para>If using FreeBSD 3.2 or earlier, at the Boot: prompt,
                  enter <literal>1:wd(2,a)kernel</literal> and press Enter.
                  If the system starts, then run the command
                  <command>echo "1:wd(2,a)kernel" &gt; /boot.config</command>
                  to make it the default boot string.</para>
              </listitem>

              <listitem>
                <para>Move the FreeBSD disk onto the primary IDE controller,
                  so the hard disks are consecutive.</para>
              </listitem>

              <listitem>
                <para><ulink URL="../handbook/kernelconfig.html">Rebuild
                  your kernel,</ulink> modify the wd configuration lines to
                  read:</para>

                  <programlisting>controller      wdc0    at isa? port "IO_WD1" bio irq 14 vector wdintr
disk            wd0     at wdc0 drive 0
# disk            wd1     at wdc0 drive 1 # comment out this line

controller      wdc1    at isa? port "IO_WD2" bio irq 15 vector wdintr
disk            wd1     at wdc1 drive 0 # change from wd2 to wd1
disk            wd2     at wdc1 drive 1 # change from wd3 to wd2</programlisting>

                <para>Install the new kernel.  If you moved your disks and
                  wish to restore the previous configuration, replace the
                  disks in the desired configuration and reboot.  Your
                  system should boot successfully.</para>
              </listitem>
            </orderedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="memory-limits">
          <para>What are the limits for memory?</para>
        </question>

        <answer>
          <para>For memory, the limit is 4 gigabytes. This configuration
            has been tested, see <ulink
            URL="ftp://ftp.cdrom.com/archive-info/configuration">wcarchive's
            configuration</ulink> for more details. If you plan to install
            this much memory into a machine, you need to be careful. You will
            probably want to use ECC memory and to reduce capacitive
            loading use 9 chip memory modules versus 18 chip memory
            modules.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ffs-limits">
          <para>What are the limits for ffs filesystems?</para>
        </question>

        <answer>
          <para>For ffs filesystems, the maximum theoretical limit is 8
            terabytes (2G blocks), or 16TB for the default block size of
            8K. In practice, there is a soft limit of 1 terabyte, but with
            modifications filesystems with 4 terabytes are possible (and
            exist).</para>

          <para>The maximum size of a single ffs file is approximately 1G
            blocks (4TB) if the block size is 4K.</para>

          <table>
            <title>Maximum file sizes</title>

            <tgroup cols="5">
              <thead>
                <row>
                  <entry>fs block size</entry>

                  <entry>2.2.7-stable</entry>

                  <entry>3.0-current</entry>

                  <entry>works</entry>

                  <entry>should work</entry>
                </row>
              </thead>

              <tbody>
                <row>
                  <entry>4K</entry>

                  <entry>4T-1</entry>

                  <entry>4T-1</entry>

                  <entry>4T-1</entry>

                  <entry>&gt;4T</entry>
                </row>

                <row>
                  <entry>8K</entry>

                  <entry>&gt;32G</entry>

                  <entry>8T-1</entry>

                  <entry>&gt;32G</entry>

                  <entry>32T-1</entry>
                </row>

                <row>
                  <entry>16K</entry>

                  <entry>&gt;128G</entry>

                  <entry>16T-1</entry>

                  <entry>&gt;128G</entry>

                  <entry>32T-1</entry>
                </row>

                <row>
                  <entry>32K</entry>

                  <entry>&gt;512G</entry>

                  <entry>32T-1</entry>

                  <entry>&gt;512G</entry>

                  <entry>64T-1</entry>
                </row>

                <row>
                  <entry>64K</entry>

                  <entry>&gt;2048G</entry>

                  <entry>64T-1</entry>

                  <entry>&gt;2048G</entry>

                  <entry>128T-1</entry>
                </row>
              </tbody>
            </tgroup>
          </table>

          <para>When the fs block size is 4K, triple indirect blocks work
            and everything should be limited by the maximum fs block number
            that can be represented using triple indirect blocks (approx.
            1K^3 + 1K^2 + 1K), but everything is limited by a (wrong) limit
            of 1G-1 on fs block numbers. The limit on fs block numbers
            should be 2G-1. There are some bugs for fs block numbers near
            2G-1, but such block numbers are unreachable when the fs block
            size is 4K.</para>

          <para>For block sizes of 8K and larger, everything should be
            limited by the 2G-1 limit on fs block numbers, but is actually
            limited by the 1G-1 limit on fs block numbers, except under
            -STABLE triple indirect blocks are unreachable, so the limit is
            the maximum fs block number that can be represented using
            double indirect blocks (approx. (blocksize/4)^2 +
            (blocksize/4)), and under -CURRENT exceeding this limit may
            cause problems. Using the correct limit of 2G-1 blocks does
            cause problems.</para>

        </answer>
      </qandaentry>

      <qandaentry>
        <question id="archsw-readin-failed-error">
          <para>Why do I get an error message,
            <errorname>archsw.readin.failed</errorname> after compiling
            and booting a new kernel?</para>
        </question>

        <answer>
          <para>You can boot by specifying the kernel directly at the second
            stage, pressing any key when the | shows up before loader is
            started. More specifically, you have upgraded the source for
            your kernel, and installed a new kernel builtin from them
            <emphasis>without making world</emphasis>. This is not
            supported. Make world.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="upgrade-3x-4x">
           <para>How do I upgrade from 3.X -&gt; 4.X?</para>
        </question>

        <answer>
          <para>We <emphasis>strongly</emphasis> recommend that you use
            binary snapshots to do this. 4-STABLE snapshots are available at
            <ulink
            URL="ftp://releng4.FreeBSD.org/">ftp://releng4.FreeBSD.org/</ulink>.</para>

          <para>Because of the many changes between 3.X and 4-STABLE,
            a direct upgrade from source will probably fail.  A source
            upgrade can be done, but only in stages.  First, upgrade
            to the latest 3-STABLE (<literal>RELENG_3</literal>).
            Then upgrade to 4.1.1-RELEASE
            (<literal>RELENG_4_1_1_RELEASE</literal>).  Finally,
            upgrade to 4-STABLE (<literal>RELENG_4</literal>).</para>

          <para>If you wish to upgrade using source, please see the <ulink
            URL="../handbook/cutting-edge.html">FreeBSD
            Handbook</ulink> for more information.</para>

          <caution>
          <para>Upgrading via source is never recommended for new
            users, and upgrading from 3.X to 4.X is even less so; make sure
            you have read the instructions carefully before attempting to
            upgrade via source.</para>
          </caution>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="security-profiles">
          <para>What are these <quote>security profiles</quote>?</para>
        </question>

        <answer>
          <para>A <quote>security profile</quote> is a set of configuration
            options that attempts to achieve the desired ratio of security
            to convenience by enabling and disabling certain programs and
            other settings.  For full details, see the <ulink
            url="../handbook/install-post.html#SECURITYPROFILE">Security
            Profile</ulink> section of the Handbook's <ulink
            url="../handbook/install-post.html">post-install
            chapter</ulink>.</para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter
    id="hardware">
    <title>Hardware compatibility</title>

    <qandaset>
      <qandaentry>
        <question id="architectures">
          <para>Does FreeBSD support architectures other than the
            x86?</para>
        </question>

        <answer>

          <para>Yes.  FreeBSD currently runs on both Intel x86 and
            DEC (now Compaq) Alpha architectures.  Interest has also
            been expressed in a port of FreeBSD to the SPARC architecture,
            join the <email>freebsd-sparc@FreeBSD.org</email> <link
            linkend="mailing"> mailing list</link> if you are interested
            in joining that project.  Most recent additions to the list of
            upcoming platforms are IA-64 and PowerPC, join the
            <email>freebsd-ia64@FreeBSD.org</email> and/or
            <email>freebsd-ppc@FreeBSD.org</email> <link
            linkend="mailing">mailing lists</link> for more information.
            For general discussion on new architectures, join
            the <email>freebsd-platforms@FreeBSD.org</email>
            <link linkend="mailing">mailing list</link>.</para>

          <para>If your machine has a different architecture and you need
            something right now, we suggest you look at <ulink
            URL="http://www.netbsd.org/">NetBSD</ulink> or <ulink
            URL="http://www.openbsd.org/">OpenBSD</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="which-hardware-to-get">
          <para>I want to get a piece of hardware for my FreeBSD
            system.  Which model/brand/type is best?</para>
        </question>

        <answer>
          <para>This is discussed continually on the FreeBSD mailing
            lists.  Since hardware changes so quickly, however, we
            expect this.  We <emphasis>still</emphasis> strongly
            recommend that you read through the 
	    <ulink URL="&rel.current.hardware;">Hardware Notes</ulink>
	    and search the mailing list
            <ulink URL="http://www.freebsd.org/search/#mailinglists">
            archives</ulink> before asking about the latest and
            greatest hardware.  Chances are a discussion about the
            type of hardware you are looking for took place just last
            week.</para>

          <para>If you are looking for a laptop, check the
            FreeBSD-mobile mailing list archives.  Otherwise, you
            probably want the archives for FreeBSD-questions, or
            possibly a specific mailing list for a particular hardware
            type.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="supported-hard-drives">
          <para>What kind of hard drives does FreeBSD support?</para>
        </question>

        <answer>
          <para>FreeBSD supports EIDE and SCSI drives (with a compatible
            controller; see the next section), and all drives using the
            original <quote>Western Digital</quote> interface (MFM, RLL,
            ESDI, and of course IDE). A few ESDI controllers that use
            proprietary interfaces may not work: stick to WD1002/3/6/7
            interfaces and clones.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="supported-scsi-controllers">
          <para>Which SCSI controllers are supported?</para>
        </question>

        <answer>
          <para>See the complete list in the current <ulink
            URL="&rel.current.hardware;">Hardware Notes</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="supported-cdrom-drives">
          <para>Which CDROM drives are supported by FreeBSD?</para>
        </question>

        <answer>
          <para>Any SCSI drive connected to a supported controller is
            supported.</para>

          <para>The following proprietary CDROM interfaces are also
            supported:</para>

            <itemizedlist>
              <listitem>
                <para>Mitsumi LU002 (8bit), LU005 (16bit) and FX001D
                  (16bit 2x Speed).</para>
              </listitem>

              <listitem>
                <para>Sony CDU 31/33A</para>
              </listitem>

              <listitem>
                <para>Sound Blaster Non-SCSI CDROM</para>
              </listitem>

              <listitem>
                <para>Matsushita/Panasonic CDROM</para>
              </listitem>

              <listitem>
                <para>ATAPI compatible IDE CDROMs</para>
              </listitem>
            </itemizedlist>

          <para>All non-SCSI cards are known to be extremely slow compared
            to SCSI drives, and some ATAPI CDROMs may not work.</para>

          <para>As of 2.2 the FreeBSD CDROM from the FreeBSD Mall supports
            booting directly from the CD.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="supported-cdrw-drives">
          <para>Which CD-RW drives are supported by FreeBSD?</para>
        </question>

	<answer>
	  <para>FreeBSD supports any ATAPI-compatible IDE CD-R or CD-RW
	    drive.  For FreeBSD versions 4.0 and later, see the man page for
	      &man.burncd.8;.  For earlier FreeBSD versions, see the examples
	    in <filename>/usr/share/examples/atapi</filename>.</para>

	  <para>FreeBSD also supports any SCSI CD-R or CD-RW drives.
	    Install and use the <command>cdrecord</command> command from the
	    ports or packages system, and make sure that you have the
	    <devicename>pass</devicename> device compiled in your
	    kernel.</para>
	</answer>
      </qandaentry>

      <qandaentry>
        <question id="zip-support">
          <para>Does FreeBSD support ZIP drives?</para>
        </question>

        <answer>
          <para>FreeBSD supports the SCSI ZIP drive out of the box, of
            course. The ZIP drive can only be set to run at SCSI target IDs
            5 or 6, but if your SCSI host adapter's BIOS supports it you
            can even boot from it.  It is not clear which host
            adapters support booting from targets other than 0 or 1,
            so you will have to consult your adapter's documentation
            if you would like to use this feature.</para>

          <para>ATAPI (IDE) Zip drives are supported in FreeBSD 2.2.6 and
            later releases.</para>

          <para>FreeBSD has contained support for Parallel Port Zip Drives
            since version 3.0. If you are using a sufficiently up to date
            version, then you should check that your kernel contains the
            <devicename>scbus0</devicename>, <devicename>da0</devicename>,
            <devicename>ppbus0</devicename>, and
            <devicename>vp0</devicename> drivers (the GENERIC kernel
            contains everything except <devicename>vp0</devicename>). With
            all these drivers present, the Parallel Port drive should be
            available as <devicename>/dev/da0s4</devicename>. Disks can be
            mounted using <command>mount /dev/da0s4 /mnt</command> OR (for
            dos disks) <command>mount_msdos /dev/da0s4 /mnt</command> as
            appropriate.</para>

          <para>Also check out <link linkend="jaz">the FAQ on removable
            drives</link> later in this chapter, and <link linkend="disklabel">the note on
            <quote>formatting</quote></link>in the Administration chapter.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="jaz-zip-removable-support">
          <para>Does FreeBSD support JAZ, EZ and other removable
            drives?</para>
        </question>

        <answer>
          <para>Apart from the IDE version of the EZ drive, these are all
            SCSI devices, so they should all look like SCSI disks to
            FreeBSD, and the IDE EZ should look like an IDE drive.</para>

          <para><anchor id="jaz">I am not sure how well FreeBSD supports
            changing the media out while running. You will of course need
            to dismount the drive before swapping media, and make sure that
            any external units are powered on when you boot the system so
            FreeBSD can see them.</para>

          <para>See <link linkend="disklabel">this note on
            <quote>formatting</quote></link>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="multiport-serial-support">
          <para>Which multi-port serial cards are supported by
            FreeBSD?</para>
        </question>

        <answer>
          <para>There is a list of these in the <ulink
            URL="../handbook/install.html#INSTALL-MISC">Miscellaneous
            devices</ulink> section of the handbook.</para>

          <para>Some unnamed clone cards have also been known to work,
            especially those that claim to be AST compatible.</para>

          <para>Check the &man.sio.4;
            man page to get more information on configuring such cards.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="usbkbd">
          <para>Does FreeBSD support my USB keyboard?</para>
        </question>

        <answer>
          <para>USB device support was added to FreeBSD 3.1.  However, it
            is still in preliminary state and may not always work as of
            version 3.2. If you want to experiment with the USB keyboard
            support, follow the procedure described below.</para>

          <procedure>
            <step>
              <para>Use FreeBSD 3.2 or later.</para>
            </step>

            <step>
              <para>Add the following lines to your kernel configuration
                file, and rebuild the kernel.</para>

              <programlisting>device  uhci
device  ohci
device  usb
device  ukbd
options KBD_INSTALL_CDEV</programlisting>

              <para>In versions of FreeBSD before 4.0, use this
                instead:</para>

              <programlisting>controller      uhci0
controller      ohci0
controller      usb0
controller      ukbd0
options         KBD_INSTALL_CDEV</programlisting>
            </step>

            <step>
              <para>Go to the <filename>/dev</filename> directory and create
                device nodes as follows:</para>

              <screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>./MAKEDEV kbd0 kbd1</userinput></screen>

            </step>

            <step>
              <para>Edit <filename>/etc/rc.conf</filename> and add the
                following lines:</para>

              <programlisting>usbd_enable="YES"
usbd_flags=""</programlisting>

            </step>
          </procedure>

          <para>After the system is rebooted, the AT keyboard becomes
            <devicename>/dev/kbd0</devicename> and the USB keyboard becomes
            <devicename>/dev/kbd1</devicename>, if both are connected to the
            system.  If there is the USB keyboard only, it will be
            <devicename>/dev/ukbd0</devicename>.</para>

          <para>If you want to use the USB keyboard in the console, you
            have to explicitly tell the console driver to use the existing
            USB keyboard. This can be done by running the following
            command as a part of system initialization.</para>

          <screen>&prompt.root; <userinput>kbdcontrol -k /dev/kbd1 &lt; /dev/ttyv0 &gt; /dev/null</userinput></screen>

          <para>Note that if the USB keyboard is the only keyboard, it is
            accessed as <devicename>/dev/kbd0</devicename>, thus, the command
            should look like:</para>

          <screen>&prompt.root; <userinput>kbdcontrol -k /dev/kbd0 &lt; /dev/ttyv0 &gt; /dev/null</userinput></screen>

          <para><filename>/etc/rc.i386</filename> is a good place to add the
            above command.</para>

          <para>Once this is done, the USB keyboard should work in the X
            environment as well without any special settings.</para>

          <para>Hot-plugging and unplugging of the USB keyboard may not
            work quite right yet. It is a good idea to connect the keyboard
            before you start the system and leave it connected until the
            system is shutdown to avoid troubles.</para>

          <para>See the &man.ukbd.4; man page for more information.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="busmouse">
          <para>I have an unusual bus mouse. How do I set it up?</para>
        </question>

        <answer>
          <para>FreeBSD supports the bus mouse and the InPort bus mouse
            from such manufactures as Microsoft, Logitech and ATI. The bus
            device driver is compiled in the GENERIC kernel by default in
            FreeBSD versions 2.X, but not included in version 3.0 or later.
            If you are building a custom kernel with the bus mouse driver,
            make sure to add the following line to the kernel config
            file</para>

          <para>In FreeBSD 3.0 or before, add:</para>

          <programlisting>device mse0 at isa? port 0x23c tty irq5 vector mseintr</programlisting>

          <para>In FreeBSD 3.X, the line should be:</para>

          <programlisting>device mse0 at isa? port 0x23c tty irq5</programlisting>

          <para>And in FreeBSD 4.X and later, the line should read:</para>

          <programlisting>device mse0 at isa? port 0x23c irq5</programlisting>

          <para>Bus mice usually comes with dedicated interface cards.
            These cards may allow you to set the port address and the IRQ
            number other than shown above. Refer to the manual of your
            mouse and the &man.mse.4; man page for more information.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ps2mouse">
          <para>How do I use my PS/2 (<quote>mouse port</quote> or
            <quote>keyboard</quote>) mouse?</para>
        </question>

        <answer>

          <para>If you are running a post-2.2.5 version of FreeBSD, the
            necessary driver, <devicename>psm</devicename>, is included and
            enabled in the kernel. The kernel should detect your PS/2 mouse
            at boot time.</para>

          <para>If you are running a previous but relatively recent version
            of FreeBSD (2.1.x or better) then you can simply enable it in
            the kernel configuration menu at installation time, otherwise
            later with <option>-c</option> at the <command>boot:</command>
            prompt. It is disabled by default, so you will need to enable
            it explicitly.</para>

          <para>If you are running an older version of FreeBSD then you will
            have to add the following lines to your kernel configuration
            file and compile a new kernel.</para>

          <para>In FreeBSD 3.0 or earlier, the line should be:</para>

          <programlisting>device psm0 at isa? port "IO_KBD" conflicts tty irq 12 vector psmintr</programlisting>

          <para>In FreeBSD 3.1 or later, the line should be:</para>

          <programlisting>device psm0 at isa? tty irq 12</programlisting>

          <para>In FreeBSD 4.0 or later, the line should be:</para>

          <programlisting>device psm0 at atkbdc? irq 12</programlisting>

          <para>See the <ulink
            URL="../handbook/kernelconfig.html">Handbook entry on
            configuring the kernel</ulink> if you have no experience with
            building kernels.</para>

          <para>Once you have a kernel detecting
            <devicename>psm0</devicename> correctly at boot time, make sure
            that an entry for <devicename>psm0</devicename> exists in
            <filename>/dev</filename>.  You can do this by typing:</para>

          <screen>&prompt.root; <userinput>cd /dev; sh MAKEDEV psm0</userinput></screen>

          <para>when logged in as <username>root</username>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="moused">
          <para>Is it possible to make use of a mouse in any way outside
            the X Window system?</para>
        </question>

        <answer>
          <para>If you are using the default console driver, syscons, you
            can use a mouse pointer in text consoles to cut &amp; paste
            text. Run the mouse daemon, moused, and turn on the mouse
            pointer in the virtual console:</para>

          <screen>&prompt.root; <userinput>moused -p /dev/<replaceable>xxxx</replaceable> -t <replaceable>yyyy</replaceable></userinput>
&prompt.root; <userinput>vidcontrol -m on</userinput></screen>

          <para>Where <replaceable>xxxx</replaceable> is the mouse device
            name and <replaceable>yyyy</replaceable> is a protocol type for
            the mouse.  See the &man.moused.8; man page for supported
            protocol types.</para>

          <para>You may wish to run the mouse daemon automatically when the
            system starts.  In version 2.2.1, set the following variables in
            <filename>/etc/sysconfig</filename>.</para>

          <programlisting>mousedtype="yyyy"
mousedport="xxxx"
mousedflags=""</programlisting>

          <para>In versions 2.2.2 to 3.0, set the following variables in
            <filename>/etc/rc.conf</filename>.</para>

          <programlisting>moused_type="yyyy"
moused_port="xxxx"
moused_flags=""</programlisting>

          <para>In 3.1 and later, assuming you have a PS/2 mouse, all you
            need to is add <literal>moused_enable="YES"</literal> to
            <filename>/etc/rc.conf</filename>.</para>

          <para>In addition, if you would like to be able to use the mouse
            daemon on all virtual terminals instead of just console at
            boot-time, add the following to
            <filename>/etc/rc.conf</filename>.</para>

          <programlisting>allscreens_flags="-m on"</programlisting>

          <para>Staring from FreeBSD 2.2.6, the mouse daemon is capable of
            determining the correct protocol type automatically unless the
            mouse is a relatively old serial mouse model. Specify
            <literal>auto</literal> the protocol to invoke automatic
            detection.</para>

          <para>When the mouse daemon is running, access to the mouse
            needs to be coordinated between the mouse daemon and other
            programs such as the X Window. Refer to <link
            linkend="x-and-moused">another section</link> on this
            issue.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="text-mode-cut-paste">
          <para>How do I cut and paste text with mouse in the text
            console?</para>
        </question>

        <answer>
          <para>Once you get the mouse daemon running (see
            <link linkend="moused">previous section</link>), hold down the
            button 1 (left button) and move the mouse to select a region of
            text. Then, press the button 2 (middle button) or the button 3
            (right button) to paste it at the text cursor.</para>

          <para>In versions 2.2.6 and later, pressing the button 2 will
            paste the text. Pressing the button 3 will
            <quote>extend</quote> the selected region of text. If your
            mouse does not have the middle button, you may wish to emulate
            it or remap buttons using moused options. See the
            &man.moused.8; man page for details.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="usbmouse">
          <para>Does FreeBSD support any USB mice?</para>
        </question>

        <answer>

          <para>Preliminary USB device support was added to FreeBSD
            3.1.  It did not always work through early versions of
            3.X.  As of FreeBSD 4.0, USB devices should work out of
            the box.  If you want to experiment with the USB mouse
            support under FreeBSD 3.X, follow the procedure described
            below.</para>

          <procedure>
            <step>
              <para>Use FreeBSD 3.2 or later.</para>
            </step>

            <step>
              <para>Add the following lines to your kernel configuration
                file, and rebuild the kernel.</para>

              <programlisting>device  uhci
device  ohci
device  usb
device  ums</programlisting>

              <para>In versions of FreeBSD before 4.0, use this
                instead:</para>

              <programlisting>controller        uhci0
controller        ohci0
controller        usb0
device            ums0</programlisting>
            </step>

            <step>
              <para>Go to the <filename>/dev</filename> directory and
                create a device node as follows:</para>

              <screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>./MAKEDEV ums0</userinput></screen>
            </step>

            <step>
              <para>Edit <filename>/etc/rc.conf</filename> and add the
                following lines:</para>

              <programlisting>moused_enable="YES"
moused_type="auto"
moused_port="/dev/ums0"
moused_flags=""
usbd_enable="YES"
usbd_flags=""</programlisting>

              <para>See the <link linkend="moused">previous section</link>
                for more detailed discussion on moused.</para>
            </step>

            <step>
              <para>In order to use the USB mouse in the X session, edit
                <filename>XF86Config</filename>.  If you are using XFree86
                3.3.2 or later, be sure to have the following lines in the
                <emphasis>Pointer</emphasis> section:</para>

              <programlisting>Device          "/dev/sysmouse"
Protocol        "Auto"</programlisting>

              <para>If you are using earlier versions of XFree86, be sure to
                have the following lines in the <emphasis>Pointer</emphasis>
                section:</para>

              <programlisting>Device          "/dev/sysmouse"
Protocol        "SysMouse"</programlisting>
            </step>
          </procedure>

          <para>Refer to <link linkend="x-and-moused">another section</link>
            on the mouse support in the X environment.</para>

          <para>Hot-plugging and unplugging of the USB mouse may not work
            quite right yet. It is a good idea connect the mouse before you
            start the system and leave it connected until the system is
            shutdown to avoid trouble.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="mouse-wheel-buttons">
          <para>My mouse has a fancy wheel and buttons.  Can I use them in
            FreeBSD?</para>
        </question>

        <answer>
          <para>The answer is, unfortunately, <quote>It depends</quote>.
            These mice with additional features require specialized driver
            in most cases. Unless the mouse device driver or the user
            program has specific support for the mouse, it will act just
            like a standard two, or three button mouse.</para>

          <para>For the possible usage of wheels in the X Window
            environment, refer to <link linkend="x-and-wheel">that
            section</link>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="psmerr">
          <para>Why does my wheel-equipped PS/2 mouse cause my mouse cursor
            to jump around the screen?</para>
        </question>

        <answer>
          <para>The PS/2 mouse driver psm in FreeBSD versions 3.2 or
            earlier has difficulty with some wheel mice, including Logitech
            model M-S48 and its OEM siblings. Apply the following patch to
            <filename>/sys/i386/isa/psm.c</filename> and rebuild the
            kernel.</para>

          <programlisting>Index: psm.c
===================================================================
RCS file: /src/CVS/src/sys/i386/isa/Attic/psm.c,v
retrieving revision 1.60.2.1
retrieving revision 1.60.2.2
diff -u -r1.60.2.1 -r1.60.2.2
--- psm.c        1999/06/03 12:41:13 1.60.2.1
+++ psm.c        1999/07/12 13:40:52 1.60.2.2
@@ -959,14 +959,28 @@
     sc->mode.packetsize = vendortype[i].packetsize;

     /* set mouse parameters */
+#if 0
+    /*
+     * A version of Logitech FirstMouse+ won't report wheel movement,
+     * if SET_DEFAULTS is sent...  Don't use this command.
+     * This fix was found by Takashi Nishida.
+     */
     i = send_aux_command(sc->kbdc, PSMC_SET_DEFAULTS);
     if (verbose >= 2)
         printf("psm%d: SET_DEFAULTS return code:%04x\n", unit, i);
+#endif
     if (sc->config & PSM_CONFIG_RESOLUTION) {
         sc->mode.resolution
             = set_mouse_resolution(sc->kbdc,
-                (sc->config & PSM_CONFIG_RESOLUTION) - 1);
+                       (sc->config & PSM_CONFIG_RESOLUTION) - 1);
+    } else if (sc->mode.resolution >= 0) {
+        sc->mode.resolution
+            = set_mouse_resolution(sc->kbdc, sc->dflt_mode.resolution);
+    }
+    if (sc->mode.rate > 0) {
+        sc->mode.rate = set_mouse_sampling_rate(sc->kbdc, sc->dflt_mode.rate);
     }
+    set_mouse_scaling(sc->kbdc, 1);

     /* request a data packet and extract sync. bits */
     if (get_mouse_status(sc->kbdc, stat, 1, 3) < 3) {</programlisting>

          <para>Versions later than 3.2 should be all right.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="laptop-mouse-trackball">
          <para>How do I use the mouse/trackball/touchpad on my
            laptop?</para>
        </question>

        <answer>
          <para>Please refer to <link linkend="ps2mouse">the answer to
            the previous question</link>.  Also check out the <ulink
            url="http://www.FreeBSD.org/docs.html#PAO">Mobile
            Computing page</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="tape-support">
          <para>What types of tape drives are supported?</para>
        </question>

        <answer>

          <para>FreeBSD supports SCSI and QIC-36 (with a QIC-02 interface).
            This includes 8-mm (aka Exabyte) and DAT drives.</para>

          <para>Some of the early 8-mm drives are not quite compatible
          with SCSI-2, and may not work well with FreeBSD.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="tape-changer-support">
          <para>Does FreeBSD support tape changers?</para>
        </question>

        <answer>
          <para>FreeBSD 2.2 supports SCSI changers using the
            &man.ch.4;
            device and the
            &man.chio.1;
            command. The details of how you actually control the changer
            can be found in the
            &man.chio.1;
            man page.</para>

          <para>If you are not using <application>AMANDA</application>
            or some other product that already understands changers,
            remember that they only know how to move a tape from one
            point to another, so you need to keep track of which slot a
            tape is in, and which slot the tape currently in the drive
            needs to go back to.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="sound-card-support">
          <para>Which sound cards are supported by FreeBSD?</para>
        </question>

        <answer>
          <para>FreeBSD supports the SoundBlaster, SoundBlaster Pro,
            SoundBlaster 16, Pro Audio Spectrum 16, AdLib and Gravis
            UltraSound sound cards. There is also limited support for
            MPU-401 and compatible MIDI cards. Cards conforming to the
            Microsoft Sound System specification are also supported through
            the pcm driver.</para>

            <note>
              <para>This is only for sound!  This driver does not support
                CDROMs, SCSI or joysticks on these cards, except for the
                SoundBlaster. The SoundBlaster SCSI interface and some
                non-SCSI CDROMS are supported, but you cannot boot off this
                device.</para>
             </note>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="es1370-silent-pcm">
          <para>Workarounds for no sound from es1370 with pcm driver?</para>
        </question>

        <answer>
          <para>You can run the following command every time the machine
            booted up:</para>

          <screen>&prompt.root; <userinput>mixer pcm 100 vol 100 cd 100</userinput></screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="network-cards">
          <para>Which network cards does FreeBSD support?</para>
        </question>

        <answer>
          <para>See the <ulink
            URL="../handbook/install.html#INSTALL-NICS">
            Ethernet cards</ulink> section of the handbook for a more
            complete list.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="no-math-coprocessor">
          <para>I do not have a math co-processor - is that bad?</para>
        </question>

        <answer>
            <note>
              <para>This will only affect 386/486SX/486SLC owners - other
                machines will have one built into the CPU.</para>
            </note>

          <para>In general this will not cause any problems, but there are
            circumstances where you will take a hit, either in performance
            or accuracy of the math emulation code (see the section <link
            linkend="emul">on FP emulation</link>). In particular, drawing
            arcs in X will be VERY slow. It is highly recommended that you
            buy a math co-processor; it is well worth it.</para>

            <note>
              <para>Some math co-processors are better than others.  It
                pains us to say it, but nobody ever got fired for buying
                Intel. Unless you are sure it works with FreeBSD, beware of
                clones.</para>
            </note>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="other-device-support">
          <para>What other devices does FreeBSD support?</para>
        </question>

        <answer>
          <para>See the <ulink
            URL="../handbook/install.html#INSTALL-MISC">Handbook</ulink>
            for the list of other devices supported.</para>

        </answer>
      </qandaentry>

      <qandaentry>
        <question id="power-management-support">
          <para>Does FreeBSD support power management on my laptop?</para>
        </question>

        <answer>
          <para>FreeBSD supports <acronym>APM</acronym> on certain machines.  Please look in
            the <filename>LINT</filename> kernel config file, searching for
            the
            <acronym>APM</acronym>
            keyword.  Further information can be found in &man.apm.4;.</para>

        </answer>
      </qandaentry>

      <qandaentry>
        <question id="micron-hang-boot">
          <para>Why does my Micron system hang at boot time?</para>
        </question>

        <answer>
          <para>Certain Micron motherboards have a non-conforming PCI BIOS
            implementation that causes grief when FreeBSD boots because PCI
            devices do not get configured at their reported addresses.</para>

          <para>Disable the <quote>Plug and Play Operating System</quote>
            flag in the BIOS to work around this problem. More information
            can be found at <ulink
            URL="http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html#micron">
            http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html#micron</ulink></para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="newer-adaptec-support">
          <para>Why does FreeBSD not recognize my Adaptec SCSI
            controller card?</para>
        </question>

        <answer>
          <para>The newer AIC789x series Adaptec chips are supported under
            the CAM SCSI framework which made its debut in 3.0. Patches
            against 2.2-STABLE are in <ulink
            URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/development/cam/">
            ftp://ftp.FreeBSD.org/pub/FreeBSD/development/cam/</ulink>.
            A CAM-enhanced boot floppy is available at <ulink
            URL="http://people.FreeBSD.org/~abial/cam-boot/">
            http://people.FreeBSD.org/~abial/cam-boot/</ulink>.
            In both cases read the README before beginning.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="internal-plugnplay-modem">
          <para>Why is FreeBSD not finding my internal Plug &amp; Play
            modem?</para>
        </question>

        <answer>
          <para>You will need to add the modem's PnP ID to the PnP ID
            list in the serial driver. To enable Plug &amp; Play support,
            compile a new kernel with <literal>controller pnp0</literal> in
            the configuration file, then reboot the system. The kernel will
            print the PnP IDs of all the devices it finds. Copy the PnP ID
            from the modem to the table in
            <filename>/sys/i386/isa/sio.c</filename>, at about line 2777.
            Look for the string <literal>SUP1310</literal> in the structure
            <literal>siopnp_ids[]</literal> to find the table. Build the
            kernel again, install, reboot, and your modem should be
            found.</para>

          <para>You may have to manually configure the PnP devices using
            the <literal>pnp</literal> command in the boot-time
            configuration with a command like</para>

          <programlisting>pnp 1 0 enable os irq0 3 drq0 0 port0 0x2f8</programlisting>

          <para>to make the modem show.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="support-winmodem">
          <para>Does FreeBSD support software modems, such as
            Winmodems?</para>
        </question>

        <answer>
          <para>FreeBSD supports many software modems via add-on
            software.  The <filename role="package">comms/ltmdm</filename> port adds
            support for modems based on the very popular Lucent LT
            chipset.  The <filename role="package">comms/mwavem</filename> port
            supports the modem in IBM Thinkpad 600 and 700
            laptops.</para>

          <para>You cannot install FreeBSD via a software modem; this
            software must be installed after the OS is
            installed.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="serial-console-prompt">
          <para>How do I get the boot: prompt to show on the serial
            console?</para>
        </question>

        <answer>
            <orderedlist>
              <listitem>
                <para>Build a kernel with
                  <literal>options COMCONSOLE</literal>.</para>
              </listitem>

              <listitem>
                <para>Create /boot.config and place <option>-P</option>
                  as the only text in the file.</para>
              </listitem>

              <listitem>
                <para>Unplug the keyboard from the system.</para>
              </listitem>
            </orderedlist>

          <para>See
            <filename>/usr/src/sys/i386/boot/biosboot/README.serial</filename>
            for information.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="micron-3comnic-failure">
          <para>Why does my 3Com PCI network card not work with my Micron
            computer?</para>
        </question>

        <answer>
          <para>Certain Micron motherboards have a non-conforming PCI BIOS
            implementation that does not configure PCI devices at the
            addresses reported. This causes grief when FreeBSD
            boots.</para>

          <para>To work around this problem, disable the
            <quote>Plug and Play Operating System</quote> flag in the
            BIOS.</para>

          <para>More information on this problem is available at URL:
            <ulink URL="http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html#micron">http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html#micron</ulink></para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="smp-support">
          <para>Does FreeBSD support Symmetric Multiprocessing (SMP)?</para>
        </question>

        <answer>
          <para>SMP is supported in 3.0-STABLE and later releases only.
            SMP is not enabled in the <emphasis>GENERIC</emphasis> kernel,
            so you will have to recompile your kernel to enable SMP. Take a
            look at <filename>/sys/i386/conf/LINT</filename> to figure out
            what options to put in your kernel config file.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="asusk7v-boot-failure">
          <para>The boot floppy hangs on a system with an ASUS K7V
            motherboard.  How do I fix this?</para>
        </question>

        <answer>
          <para>Go in to the BIOS setup and disable the <quote>boot virus
            protection</quote>.</para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="troubleshoot">
    <title>Troubleshooting</title>

    <qandaset>
      <qandaentry>
        <question id="awre">
          <para>What do I do when I have bad blocks on my hard drive?</para>
        </question>

        <answer>
          <para>With SCSI drives, the drive should be capable of re-mapping
            these automatically.  However, many drives are shipped with
            this feature disabled, for some mysterious reason...</para>

          <para>To enable this, you will need to edit the first device page
            mode, which can be done on FreeBSD by giving the command
            (as <username>root</username>)</para>

          <screen>&prompt.root; <userinput>scsi -f /dev/rsd0c -m 1 -e -P 3</userinput></screen>

          <para>and changing the values of AWRE and ARRE from 0 to 1:-</para>

          <programlisting>AWRE (Auto Write Reallocation Enbld):  1
ARRE (Auto Read Reallocation Enbld):  1</programlisting>

          <para>The following paragraphs were submitted by Ted Mittelstaedt
            <email>tedm@toybox.placo.com</email>:</para>

          <para>For IDE drives, any bad block is usually a sign of
            potential trouble. All modern IDE drives come with internal
            bad-block remapping turned on. All IDE hard drive manufacturers
            today offer extensive warranties and will replace drives with
            bad blocks on them.</para>

          <para>If you still want to attempt to rescue an IDE drive with
            bad blocks, you can attempt to download the IDE drive
            manufacturer's IDE diagnostic program, and run this against the
            drive. Sometimes these programs can be set to force the drive
            electronics to rescan the drive for bad blocks and lock them
            out.</para>

          <para>For ESDI, RLL and MFM drives, bad blocks are a normal part
            of the drive and are no sign of trouble, generally. With a PC,
            the disk drive controller card and BIOS handle the task of
            locking out bad sectors. This is fine for operating systems
            like DOS that use BIOS code to access the disk. However,
            FreeBSD's disk driver does not go through BIOS, therefore a
            mechanism, bad144, exists that replaces this functionality.
            bad144 only works with the wd driver (which means it is not
            supported in FreeBSD 4.0), it is NOT able to be used with SCSI.
            bad144 works by entering all bad sectors found into a special
            file.</para>

          <para>One caveat with bad144 - the bad block special file is
            placed on the last track of the disk. As this file may possibly
            contain a listing for a bad sector that would occur near the
            beginning of the disk, where the /kernel file might be located,
            it therefore must be accessible to the bootstrap program that
            uses BIOS calls to read the kernel file. This means that the
            disk with bad144 used on it must not exceed 1024 cylinders, 16
            heads, and 63 sectors. This places an effective limit of 500MB
            on a disk that is mapped with bad144.</para>

          <para>To use bad144, simply set the <quote>Bad Block</quote>
            scanning to ON in the FreeBSD fdisk screen during the initial
            install. This works up through FreeBSD 2.2.7. The disk must
            have less than 1024 cylinders. It is generally recommended that
            the disk drive has been in operation for at least 4 hours prior
            to this to allow for thermal expansion and track
            wandering.</para>

          <para>If the disk has more than 1024 cylinders (such as a large
            ESDI drive) the ESDI controller uses a special translation mode
            to make it work under DOS. The wd driver understands about
            these translation modes, IF you enter the
            <quote>translated</quote> geometry with the <quote>set
            geometry</quote> command in fdisk. You must also NOT use the
            <quote>dangerously dedicated</quote> mode of creating the
            FreeBSD partition, as this ignores the geometry. Also, even
            though fdisk will use your overridden geometry, it still knows
            the true size of the disk, and will attempt to create a too
            large FreeBSD partition. If the disk geometry is changed to the
            translated geometry, the partition MUST be manually created
            with the number of blocks.</para>

          <para>A quick trick to use is to set up the large ESDI disk with
            the ESDI controller, boot it with a DOS disk and format it with
            a DOS partition. Then, boot the FreeBSD install and in the
            fdisk screen, read off and write down the blocksize and block
            numbers for the DOS partition. Then, reset the geometry to the
            same that DOS uses, delete the DOS partition, and create a
            <quote>cooperative</quote> FreeBSD partition using the
            blocksize you recorded earlier. Then, set the partition
            bootable and turn on bad block scanning. During the actual
            install, bad144 will run first, before any filesystems are
            created. (you can view this with an Alt-F2) If it has any
            trouble creating the badsector file, you have set too large a
            disk geometry - reboot the system and start all over again
            (including repartitioning and reformatting with DOS).</para>

          <para>If remapping is enabled and you are seeing bad blocks,
            consider replacing the drive. The bad blocks will only get
            worse as time goes on.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="bustek742a-eisa-scsi">
          <para>Why does FreeBSD not recognize my Bustek 742a EISA
            SCSI controller?</para>
        </question>

        <answer>
          <para>This info is specific to the 742a but may also cover
            other Buslogic cards.  (Bustek = Buslogic)</para>

          <para>There are 2 general <quote>versions</quote> of the 742a
            card. They are hardware revisions A-G, and revisions H -
            onwards. The revision letter is located after the Assembly
            number on the edge of the card. The 742a has 2 ROM chips on it,
            one is the BIOS chip and the other is the Firmware chip.
            FreeBSD does not care what version of BIOS chip you have but it
            does care about what version of firmware chip. Buslogic will
            send upgrade ROMS out if you call their tech support dept. The
            BIOS and Firmware chips are shipped as a matched pair. You must
            have the most current Firmware ROM in your adapter card for
            your hardware revision.</para>

          <para>The REV A-G cards can only accept BIOS/Firmware sets up to
            2.41/2.21. The REV H- up cards can accept the most current
            BIOS/Firmware sets of 4.70/3.37. The difference between the
            firmware sets is that the 3.37 firmware supports <quote>round
            robin</quote></para>

          <para>The Buslogic cards also have a serial number on them.  If
            you have a old hardware revision card you can call the Buslogic
            RMA department and give them the serial number and attempt to
            exchange the card for a newer hardware revision. If the card is
            young enough they will do so.</para>

          <para>FreeBSD 2.1 only supports Firmware revisions 2.21 onward.
            If you have a Firmware revision older than this your card will
            not be recognized as a Buslogic card. It may be recognized as
            an Adaptec 1540, however. The early Buslogic firmware contains
            an AHA1540 <quote>emulation</quote> mode. This is not a good
            thing for an EISA card, however.</para>

          <para>If you have an old hardware revision card and you obtain
            the 2.21 firmware for it, you will need to check the position
            of jumper W1 to B-C, the default is A-B.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="hpnetserver-scsi-failure">
          <para>Why does FreeBSD not detect my HP Netserver's SCSI
            controller?</para>
        </question>

        <answer>
          <para>This is basically a known problem.  The EISA on-board SCSI
            controller in the HP Netserver machines occupies EISA slot
            number 11, so all the <quote>true</quote> EISA slots are in
            front of it. Alas, the address space for EISA slots &gt;= 10
            collides with the address space assigned to PCI, and FreeBSD's
            auto-configuration currently cannot handle this situation very
            well.</para>

          <para>So now, the best you can do is to pretend there is no
            address range clash :), by bumping the kernel option
            <literal>EISA_SLOTS</literal> to a value of 12. Configure and
            compile a kernel, as described in the <ulink
            URL="../handbook/kernelconfig.html">Handbook entry on
            configuring the kernel</ulink>.</para>

          <para>Of course, this does present you with a chicken-and-egg
            problem when installing on such a machine. In order to work
            around this problem, a special hack is available inside
            <emphasis>UserConfig</emphasis>. Do not use the
            <quote>visual</quote> interface, but the plain command-line
            interface there. Simply type</para>

          <programlisting>eisa 12
quit</programlisting>

          <para>at the prompt, and install your system as usual.  While
            it is recommended you compile and install a custom kernel
            anyway.</para>

          <para>Hopefully, future versions will have a proper fix for
            this problem.</para>

            <note>
              <para>You cannot use a
                <literal>dangerously dedicated</literal> disk
                with an HP Netserver. See <link linkend="dedicate">this
                note</link> for more info.</para>
            </note>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="cmd640-ide">
          <para>What is going on with my CMD640 IDE controller?</para>
        </question>

        <answer>
          <para>It is broken.  It cannot handle commands on both channels
            simultaneously.</para>

          <para>There is a workaround available now and it is enabled
            automatically if your system uses this chip. For the details
            refer to the manual page of the disk driver (man 4 wd).</para>

          <para>If you are already running FreeBSD 2.2.1 or 2.2.2 with a
            CMD640 IDE controller and you want to use the second channel,
            build a new kernel with <literal>options "CMD640"</literal>
            enabled. This is the default for 2.2.5 and later.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ed1-timeout">
          <para>I keep seeing messages like
            <errorname>ed1: timeout</errorname>.  What do these messages
            mean?</para>
        </question>

        <answer>
          <para>This is usually caused by an interrupt conflict (e.g.,
            two boards using the same IRQ). FreeBSD prior to 2.0.5R used to
            be tolerant of this, and the network driver would still
            function in the presence of IRQ conflicts. However, with 2.0.5R
            and later, IRQ conflicts are no longer tolerated. Boot with the
            -c option and change the ed0/de0/... entry to match your
            board.</para>

          <para>If you are using the BNC connector on your network card,
            you may also see device timeouts because of bad termination. To
            check this, attach a terminator directly to the NIC (with no
            cable) and see if the error messages go away.</para>

          <para>Some NE2000 compatible cards will give this error if there
            is no link on the UTP port or if the cable is disconnected.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="bad-3c509">
          <para>Why did my 3COM 3C509 card stop working for no
            apparent reason?</para>
        </question>

        <answer>
          <para>This card has a bad habit of losing its configuration
            information.  Refresh your card's settings with the DOS
            utility <command>3c5x9.exe</command>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="printer-slow">
          <para>My parallel printer is ridiculously slow. What can I do?</para>
        </question>

        <answer>
          <para>If the only problem is that the printer is terribly
            slow, try changing your <ulink
            url="../handbook/printing-intro-setup.html#PRINTING-PARALLEL-PORT-MODE">printer
            port mode</ulink> as discussed in the <ulink
            url="../handbook/printing-intro-setup.html">Printer
            Setup</ulink> section of the Handbook.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="signal11">
          <para>Why do my programs occasionally die with
            <errorname>Signal 11</errorname> errors?</para>
        </question>

        <answer>
          <para>Signal 11 errors are caused when your process has attempted
            to access memory which the operating system has not granted it
            access to. If something like this is happening at seemingly
            random intervals then you need to start investigating things
            very carefully.</para>

          <para>These problems can usually be attributed to either:</para>

          <orderedlist>
            <listitem>
              <para>If the problem is occurring only in a specific
                application that you are developing yourself it is probably
                a bug in your code.</para>
            </listitem>

            <listitem>
              <para>If it is a problem with part of the base FreeBSD system,
                it may also be buggy code, but more often than not these
                problems are found and fixed long before us general FAQ
                readers get to use these bits of code (that is what -current
                is for).</para>
            </listitem>
          </orderedlist>

          <para>In particular, a dead giveaway that this is <emphasis>not</emphasis> a FreeBSD
            bug is if you see the problem when you are compiling a program,
            but the activity that the compiler is carrying out changes
            each time.</para>

          <para>For example, suppose you are running <quote>make
            buildworld</quote>, and the compile fails while trying to
            compile <filename>ls.c</filename> in to
            <filename>ls.o</filename>. If you then run <quote>make
            buildworld</quote> again, and the compile fails in the same
            place then this is a broken build -- try updating your sources
            and try again. If the compile fails elsewhere then this is
            almost certainly hardware.</para>

          <para>What you should do:</para>

          <para>In the first case you can use a debugger e.g. gdb to find
            the point in the program which is attempting to access a bogus
            address and then fix it.</para>

          <para>In the second case you need to verify that it is not your
            hardware at fault.</para>

          <para>Common causes of this include:</para>

          <orderedlist>
            <listitem>
              <para>Your hard disks might be overheating: Check the fans in
                your case are still working, as your disk (and perhaps
                other hardware might be overheating).</para>
            </listitem>

            <listitem>
              <para>The processor running is overheating: This might be
                because the processor has been overclocked, or the fan on
                the processor might have died. In either case you need to
                ensure that you have hardware running at what it is
                specified to run at, at least while trying to solve this
                problem. i.e. Clock it back to the default settings.</para>

              <para>If you are overclocking then note that it is far cheaper
                to have a slow system than a fried system that needs
                replacing! Also the wider community is not often
                sympathetic to problems on overclocked systems, whether you
                believe it is safe or not.</para>
            </listitem>

            <listitem>
              <para>Dodgy memory: If you have multiple memory SIMMS/DIMMS
                installed then pull them all out and try running the
                machine with each SIMM or DIMM individually and narrow the
                problem down to either the problematic DIMM/SIMM or perhaps
                even a combination.</para>
            </listitem>

            <listitem>
              <para>Over-optimistic Motherboard settings: In your BIOS
                settings, and some motherboard jumpers you have options to
                set various timings, mostly the defaults will be
                sufficient, but sometimes, setting the wait states on RAM
                too low, or setting the <quote>RAM Speed: Turbo</quote> option, or
                similar in the BIOS will cause strange behaviour. A
                possible idea is to set to BIOS defaults, but it might be
                worth noting down your settings first!</para>
            </listitem>

            <listitem>
              <para>Unclean or insufficient power to the motherboard. If you
                have any unused I/O boards, hard disks, or CDROMs in your
                system, try temporarily removing them or disconnecting the
                power cable from them, to see if your power supply can
                manage a smaller load. Or try another power supply,
                preferably one with a little more power (for instance, if
                your current power supply is rated at 250 Watts try one
                rated at 300 Watts).</para>
            </listitem>

          </orderedlist>

          <para>You should also read the SIG11 FAQ (listed below) which has
            excellent explanations of all these problems, albeit from a
            Linux viewpoint. It also discusses how memory testing software
            or hardware can still pass faulty memory.</para>

          <para>Finally, if none of this has helped it is possible that
            you have just found a bug in FreeBSD, and you should follow the
            instructions to send a problem report.</para>

          <para>There is an extensive FAQ on this at <ulink
            URL="http://www.bitwizard.nl/sig11/">
            the SIG11 problem FAQ</ulink></para>
          </answer>
        </qandaentry>

        <qandaentry>
          <question id="trap-12-panic">
            <para>My system crashes with either <errorname>Fatal
              trap 12: page fault in kernel mode</errorname>, or
              <errorname>panic:</errorname>, and spits out a
              bunch of information.  What should I do?</para>
          </question>

          <answer>
            <para>The FreeBSD developers are very interested in these
              errors, but need some more information than just the
              error you see.  Copy your full crash message.  Then
              consult the FAQ section on <link linkend=
              "KERNEL-PANIC-TROUBLESHOOTING">kernel panics</link>,
              build a debugging kernel, and get a backtrace.  This
              might sound difficult, but you do not need any
              programming skills; you just have to follow the
              instructions.</para>
          </answer>
        </qandaentry>

        <qandaentry>
          <question id="screen-loses-sync">
            <para>Why does the screen go black and lose sync when I
              boot?</para>
          </question>

          <answer>
            <para>This is a known problem with the ATI Mach 64 video card.
              The problem is that this card uses address
              <literal>2e8</literal>, and the fourth serial port does too.
              Due to a bug (feature?) in the &man.sio.4;
              driver it will touch this port even if you do not have the
              fourth serial port, and <emphasis>even</emphasis> if
              you disable sio3 (the fourth port) which normally uses this
              address.</para>

            <para>Until the bug has been fixed, you can use this
              workaround:</para>

              <orderedlist>
                <listitem>
                  <para>Enter <option>-c</option> at the boot prompt.
                    (This will put the kernel into configuration mode).</para>
                </listitem>

                <listitem>
                  <para>Disable <devicename>sio0</devicename>,
                    <devicename>sio1</devicename>,
                    <devicename>sio2</devicename> and
                    <devicename>sio3</devicename> (all of them).  This way
                    the sio driver does not get activated -&gt; no
                    problems.</para>
                </listitem>

                <listitem>
                  <para>Type exit to continue booting.</para>
                </listitem>
              </orderedlist>

          <para>If you want to be able to use your serial ports, you will
            have to build a new kernel with the following modification: in
            <filename>/usr/src/sys/i386/isa/sio.c</filename> find the one
            occurrence of the string <literal>0x2e8</literal> and remove
            that string and the preceding comma (keep the trailing comma).
            Now follow the normal procedure of building a new
            kernel.</para>

          <para>Even after applying these workarounds, you may still find
            that the X Window System does not work properly. If this is the
            case, make sure that the XFree86 version you are using is at
            least XFree86 3.3.3 or higher. This version and upwards has
            built-in support for the Mach64 cards and even a dedicated X
            server for those cards.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="reallybigram">
          <para>Why does FreeBSD only use 64 MB of RAM when my system has
            128 MB of RAM installed?</para>
        </question>

        <answer>
          <para>Due to the manner in which FreeBSD gets the memory size
            from the BIOS, it can only detect 16 bits worth of Kbytes in
            size (65535 Kbytes = 64MB) (or less... some BIOSes peg the
            memory size to 16M). If you have more than 64MB, FreeBSD will
            attempt to detect it; however, the attempt may fail.</para>

          <para>To work around this problem, you need to use the kernel
            option specified below. There is a way to get complete memory
            information from the BIOS, but we do not have room in the
            bootblocks to do it. Someday when lack of room in the
            bootblocks is fixed, we will use the extended BIOS functions to
            get the full memory information...but for now we are stuck with
            the kernel option.</para>

          <para><literal>options "MAXMEM=<replaceable>n</replaceable>"</literal></para>

          <para>Where <replaceable>n</replaceable> is your memory in
            Kilobytes. For a 128 MB machine, you would want to use
            <literal>131072</literal>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="panic-kmemmap-too-small">
          <para>Why does FreeBSD 2.0 panic with
            <errorname>kmem_map too small!</errorname>?</para>
        </question>

        <answer>
            <note>
              <para>The message may also be
                <literal>mb_map too small!</literal></para>
            </note>

          <para>The panic indicates that the system ran out of virtual
            memory for network buffers (specifically, mbuf clusters). You
            can increase the amount of VM available for mbuf clusters by
            adding:</para>

          <para><literal>options "NMBCLUSTERS=<replaceable>n</replaceable>"</literal></para>

          <para>to your kernel config file, where
            <replaceable>n</replaceable> is a number in the range 512-4096,
            depending on the number of concurrent TCP connections you need
            to support. I would recommend trying 2048 - this should get rid of
            the panic completely. You can monitor the number of mbuf
            clusters allocated/in use on the system with
            <command>netstat
            -m</command> (see &man.netstat.1;). The default value for NMBCLUSTERS is <literal>512 +
            MAXUSERS * 16</literal>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="proc-table-full">
          <para>Why do I get the error <errorname>/kernel: proc: table
            is full</errorname>?</para>
        </question>

        <answer>
          <para>The FreeBSD kernel will only allow a certain number of
            processes to exist at one time.  The number is based on
            the <literal>MAXUSERS</literal> option in the kernel
            configuration.  <literal>MAXUSERS</literal> also affects
            various other in-kernel limits, such as network buffers
            (see <link linkend="panic-kmemmap-too-small">this</link>
            earlier question).  If your machine is heavily loaded, you
            probably want to increase <literal>MAXUSERS</literal>.
            This will increase these other system limits in addition
            to the maximum number of processes.</para>

          <para>After FreeBSD 4.4, <literal>MAXUSERS</literal> became
            a tunable value that could be set with
            <varname>kern.maxusers</varname> in
            <filename>/boot/loader.conf</filename>.  In earlier
            versions of FreeBSD, you need to adjust
            <literal>MAXUSERS</literal> in your kernel
            configuration.</para>

          <para>If your machine is lightly loaded, and you are simply
            running a very large number of processes, you can adjust
            this with the <varname>kern.maxproc</varname> sysctl.  If
            these processes are being run by a single user, you will
            also need to adjust <varname>kern.maxprocperuid</varname>
            to be one less than your new
            <varname>kern.maxproc</varname> value.  (It must be at
            least one less because one system program, &man.init.8;,
            must always be running.)</para>

          <para>To make a sysctl permanent across reboots, set this in
            <filename>/etc/sysctl.conf</filename> in recent versions
            of FreeBSD, or <filename>/etc/rc.local</filename> in older
            versions.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="cmap-busy-panic">
          <para>Why do I get an error reading <errorname>CMAP
              busy</errorname> when rebooting with a new
            kernel?</para>
        </question>

        <answer>
          <para>The logic that attempts to detect an out of date
            <filename>/var/db/kvm_*.db</filename> files sometimes fails
            and using a mismatched file can sometimes lead to panics.</para>

          <para>If this happens, reboot single-user and do:</para>

          <screen>&prompt.root; <userinput>rm /var/db/kvm_*.db</userinput></screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="brkadrint-illegal-host-access">
          <para>What does the message <errorname>ahc0: brkadrint,
              Illegal Host Access at seqaddr 0x0</errorname>
            mean?</para>
        </question>

        <answer>
          <para>This is a conflict with an Ultrastor SCSI Host Adapter.</para>

          <para>During the boot process enter the kernel configuration
            menu and disable
            <devicename>uha0</devicename>,
            which is causing the problem.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="aci0-illegal-cable">
          <para>When I boot my system, I get the error
            <errorname>ahc0: illegal cable configuration</errorname>.
            My cabling is correct.  What is going on?</para>
        </question>

        <answer>
           <para>Your motherboard lacks the external logic to support
             automatic termination.  Switch your SCSI BIOS to specify
             the correct termination for your configuration rather
             than automatic termination.  The AIC7XXX driver cannot
             determine if the external logic for cable detection (and
             thus auto-termination) is available.  The driver simply
             assumes that this support must exist if the configuration
             contained in the serial EEPROM is set to "automatic
             termination".  Without the external cable detection logic
             the driver will often configure termination incorrectly,
             which can compromise the reliability of the SCSI
             bus.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="mail-loopback">
          <para>Why does Sendmail give me an error reading
            <quote><errorname>mail loops back to
              myself</errorname></quote>?</para>
        </question>

        <answer>
          <para>This is answered in the sendmail FAQ as follows:-</para>

<literallayout>        * I'm getting "Local configuration error" messages, such as:

        553 relay.domain.net config error: mail loops back to myself
        554 &lt;user@domain.net&gt;... Local configuration error

        How can I solve this problem?

        You have asked mail to the domain (e.g., domain.net) to be
        forwarded to a specific host (in this case, relay.domain.net)
        by using an MX record, but the relay machine does not recognize
        itself as domain.net.  Add domain.net to /etc/sendmail.cw
        (if you are using FEATURE(use_cw_file)) or add "Cw domain.net"
        to /etc/sendmail.cf.
            </literallayout>

          <para>The current version of the <ulink
            URL="ftp://rtfm.mit.edu/pub/usenet/news.answers/mail/sendmail-faq">sendmail
            FAQ</ulink> is no longer maintained with the sendmail release.
            It is however regularly posted to <ulink
            URL="news:comp.mail.sendmail">comp.mail.sendmail</ulink>,
            <ulink URL="news:comp.mail.misc">comp.mail.misc</ulink>, <ulink
            URL="news:comp.mail.smail">comp.mail.smail</ulink>, <ulink
            URL="news:comp.answers">comp.answers</ulink>, and <ulink
            URL="news:news.answers">news.answers</ulink>. You can also
            receive a copy via email by sending a message to
            <email>mail-server@rtfm.mit.edu</email> with the command
            <literal>send usenet/news.answers/mail/sendmail-faq</literal>
            as the body of the message.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="remote-fullscreen">
          <para>Why do full screen applications on remote machines
            misbehave?</para>
        </question>

        <answer>
          <para>The remote machine may be setting your terminal type
            to something other than the <literal>cons25</literal> terminal
            type required by the FreeBSD console.</para>

          <para>There are a number of possible work-arounds for this
            problem:</para>
            <itemizedlist>
              <listitem>
                <para>After logging on to the remote machine, set your
                  TERM shell variable to <literal>ansi</literal> or
                  <literal>sco</literal> if the remote machine knows
                  about these terminal types.</para>
              </listitem>

              <listitem>
                <para>Use a VT100 emulator like
                  <application>screen</application> at the FreeBSD console.
                  <application>screen</application> offers you the ability
                  to run multiple concurrent sessions from one terminal,
                  and is a neat program in its own right. Each
                  <application>screen</application> window behaves like a
                  VT100 terminal, so the TERM variable at the remote end
                  should be set to <literal>vt100</literal>.</para>
              </listitem>

              <listitem>
                <para>Install the <literal>cons25</literal> terminal
                  database entry on the remote machine. The way to do this
                  depends on the operating system on the remote machine.
                  The system administration manuals for the remote system
                  should be able to help you here.</para>
              </listitem>

              <listitem>
                <para>Fire up an X server at the FreeBSD end and login to
                  the remote machine using an X based terminal emulator
                  such as <command>xterm</command> or
                  <command>rxvt</command>. The TERM variable at the remote
                  host should be set to <literal>xterm</literal> or
                  <literal>vt100</literal>.</para>
              </listitem>
            </itemizedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="calcru-negative">
          <para>Why does my machine print
            <errorname>calcru: negative time...</errorname>?</para>
        </question>

        <answer>
          <para>This can be caused by various hardware and/or software
            ailments relating to interrupts. It may be due to bugs but can
            also happen by nature of certain devices. Running TCP/IP over
            the parallel port using a large MTU is one good way to provoke
            this problem. Graphics accelerators can also get you here, in
            which case you should check the interrupt setting of the card
            first.</para>

          <para>A side effect of this problem are dying processes with the
            message <quote>SIGXCPU exceeded cpu time limit</quote>.</para>

          <para>For FreeBSD 3.0 and later from Nov 29, 1998 forward: If the
            problem cannot be fixed otherwise the solution is to set
            this sysctl variable:</para>

          <screen>&prompt.root; <userinput>sysctl -w kern.timecounter.method=1</userinput></screen>

          <para>This means a performance impact, but considering the cause
            of this problem, you probably will not notice. If the problem
            persists, keep the sysctl set to one and set the
            <literal>NTIMECOUNTER</literal> option in your kernel to
            increasingly large values. If by the time you have reached
            <literal>NTIMECOUNTER=20</literal> the problem is not solved,
            interrupts are too hosed on your machine for reliable
            time keeping.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="pcm0-not-found">
          <para>I see <errorname>pcm0 not found</errorname> or my sound card is
            found as <devicename>pcm1</devicename> but I have
            <literal>device pcm0</literal> in my kernel config file.  What is
            going on?</para>
        </question>

        <answer>
          <para>This occurs in FreeBSD 3.x with PCI sound cards. The
            <devicename>pcm0</devicename> device is reserved exclusively for
            ISA-based cards so, if you have a PCI card, then you will see
            this error, and your card will appear as <devicename>pcm1</devicename>.

            <note>
              <para>You cannot remove the warning by simply changing the
                line in the kernel config file to <literal>device
                pcm1</literal> as this will result in
                <devicename>pcm1</devicename> being reserved for ISA cards and
                your PCI card being found as <devicename>pcm2</devicename> (along
                with the warning <errorname>pcm1 not found</errorname>).</para>
            </note>

            If you have a PCI sound card you will also have to make the
            <devicename>snd1</devicename> device rather than
            <devicename>snd0</devicename>:</para>

          <screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>./MAKEDEV snd1</userinput></screen>

          <para>This situation does not arise in FreeBSD 4.x as a lot
            of work has been done to make it more
            <emphasis>PnP-centric</emphasis> and the
            <devicename>pcm0</devicename> device is no longer reserved
            exclusively for ISA cards</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="pnp-not-found">
          <para>Why is my PnP card no longer found (or found as
            <literal>unknown</literal>) since upgrading to FreeBSD 4.x?</para>
        </question>

        <answer>
          <para>FreeBSD 4.x is now much more <emphasis>PnP-centric</emphasis>
            and this has had the side effect of some PnP devices (e.g. sound
            cards and internal modems) not working even though they worked
            under FreeBSD 3.x.</para>

          <para>The reasons for this behaviour are explained by the following
            e-mail, posted to the freebsd-questions mailing list by Peter
            Wemm, in answer to a question about an internal modem that was
            no longer found after an upgrade to FreeBSD 4.x (the comments
            in <literal>[]</literal> have been added to clarify the
            context.</para>

          <blockquote>
            <para>The PNP bios preconfigured it [the modem] and left it
              laying around in port space, so [in 3.x] the old-style ISA
              probes <quote>found</quote> it there.</para>

            <para>Under 4.0, the ISA code is much more PnP-centric. It was
              possible [in 3.x] for an ISA probe to find a
              <quote>stray</quote> device and then for the PNP device id to
              match and then fail due to resource conflicts. So, it
              disables the programmable cards first so this double probing
              cannot happen. It also means that it needs to know the PnP
              id's for supported PnP hardware. Making this more user
              tweakable is on the TODO list.</para>
          </blockquote>

          <para>To get the device working again requires finding its PnP id
            and adding it to the list that the ISA probes use to identify
            PnP devices. This is obtained using &man.pnpinfo.8; to probe the
            device, for example this is the output from &man.pnpinfo.8; for
            an internal modem:</para>

          <screen>&prompt.root; <userinput>pnpinfo</userinput>
Checking for Plug-n-Play devices...

Card assigned CSN #1
Vendor ID PMC2430 (0x3024a341), Serial Number 0xffffffff
PnP Version 1.0, Vendor Version 0
Device Description: Pace 56 Voice Internal Plug & Play Modem

Logical Device ID: PMC2430 0x3024a341 #0
        Device supports I/O Range Check
TAG Start DF
    I/O Range 0x3f8 .. 0x3f8, alignment 0x8, len 0x8
        [16-bit addr]
    IRQ: 4  - only one type (true/edge)</screen>

          <para>[more TAG lines elided]</para>

          <screen>TAG End DF
End Tag

Successfully got 31 resources, 1 logical fdevs
-- card select # 0x0001

CSN PMC2430 (0x3024a341), Serial Number 0xffffffff

Logical device #0
IO:  0x03e8 0x03e8 0x03e8 0x03e8 0x03e8 0x03e8 0x03e8 0x03e8
IRQ 5 0
DMA 4 0
IO range check 0x00 activate 0x01</screen>

          <para>The information you require is in the
            <quote>Vendor ID</quote> line at the start of the output. The
            hexadecimal number in parentheses (0x3024a341 in this example)
            is the PnP id and the string immediately before this (PMC2430)
            is a unique ASCII id. This information needs adding to the file
            <filename>/usr/src/sys/isa/sio.c</filename>.</para>

          <para>You should first make a backup of <filename>sio.c</filename>
            just in case things go wrong. You will also need it to make the
            patch to submit with your PR (you are going to submit a PR,
            are you not?) then edit <filename>sio.c</filename> and search
            for the line</para>

          <programlisting>static struct isa_pnp_id sio_ids[] = {</programlisting>

          <para>then scroll down to find the correct place to add the entry
            for your device. The entries look like this, and are sorted on
            the ASCII Vendor ID string which should be included in the
            comment to the right of the line of code along with all (if it
            will fit) or part of the <emphasis>Device Description</emphasis>
            from the output of &man.pnpinfo.8;:</para>

          <programlisting>{0x0f804f3f, NULL},     /* OZO800f - Zoom 2812 (56k Modem) */
{0x39804f3f, NULL},     /* OZO8039 - Zoom 56k flex */
{0x3024a341, NULL},     /* PMC2430 - Pace 56 Voice Internal Modem */
{0x1000eb49, NULL},     /* ROK0010 - Rockwell ? */
{0x5002734a, NULL},     /* RSS0250 - 5614Jx3(G) Internal Modem */</programlisting>

          <para>Add the hexadecimal Vendor ID for your device in the
            correct place, save the file, rebuild your kernel, and reboot.
            Your device should now be found as an <literal>sio</literal>
            device as it was under FreeBSD 3.x</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="nlist-failed">
          <para>Why do I get the error <errorname>nlist failed</errorname> when
            running, for example, <command>top</command> or
            <command>systat</command>?</para>
        </question>

        <answer>
          <para>The problem is that the application you are trying to run is
            looking for a specific kernel symbol, but, for whatever reason,
            cannot find it; this error stems from one of two problems:</para>

          <itemizedlist>
            <listitem>
              <para>Your kernel and userland are not synchronized (i.e., you
                built a new kernel but did not do an
                <maketarget>installworld</maketarget>, or vice versa), and
                thus the symbol table is different from what the user
                application thinks it is.  If this is the case, simply
                complete the upgrade process (see
                <filename>/usr/src/UPDATING</filename> for the correct
                sequence).</para>
            </listitem>

            <listitem>
              <para>You are not using <command>/boot/loader</command> to load
                your kernel, but doing it directly from boot2 (see
                &man.boot.8;).  While there is nothing wrong with bypassing
                <command>/boot/loader</command>, it generally does a better
                job of making the kernel symbols available to user
                applications.</para>
            </listitem>
          </itemizedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="connection-delay">
          <para>Why does it take so long to connect to my computer via
            <command>ssh</command> or <command>telnet</command>?</para>
        </question>

        <answer>
          <para>The symptom: there is a long delay between the time the TCP
            connection is established and the time when the client software
            asks for a password (or, in &man.telnet.1;'s case, when a login
            prompt appears).</para>

          <para>The problem: more likely than not, the delay is caused by
            the server software trying to resolve the client's IP address
            into a hostname.  Many servers, including the Telnet and SSH
            servers that come with FreeBSD, do this in order to, among
            other things, store the hostname in a log file for future
            reference by the administrator.</para>

          <para>The remedy: if the problem occurs whenever you connect from
            your computer (the client) to any server, the problem is with
            the client; likewise, if the problem only occurs when someone
            connects to your computer (the server) the problem is with the
            server.</para>

          <para>If the problem is with the client, the only remedy is to
            fix the DNS so the server can resolve it.  If this is on a
            local network, consider it a server problem and keep reading;
            conversely, if this is on the global Internet, you will most
            likely need to contact your ISP and ask them to fix it for
            you.</para>

          <para>If the problem is with the server, and this is on a local
            network, you need to configure the server to be able to resolve
            address-to-hostname queries for your local address range.  See
            the &man.hosts.5; and &man.named.8; manual pages for more
            information.  If this is on the global Internet, the problem
            may be that your server's resolver is not functioning
            correctly.  To check, try to look up another host--say,
            <hostid>www.yahoo.com</hostid>.  If it does not work, that is
            your problem.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="stray-irq">
          <para>What does <errorname>stray IRQ</errorname> mean?</para>
        </question>
	<answer>
	  <para>Stray IRQs are indications of hardware IRQ glitches,
            mostly from hardware that removes its interrupt request in
            the middle of the interrupt request acknowledge
            cycle.</para>
	  <para>One has three options for dealing with this:</para>
	  <itemizedlist>
	    <listitem>
	      <para>Live with the warnings.  All except the first 5
                per irq are suppressed anyway.</para>
	    </listitem>
	    <listitem>
	      <para>Break the warnings by changing 5 to 0 in
	        <function>isa_strayintr()</function> so that all the
	        warnings are suppressed.</para>
	    </listitem>
	    <listitem>
	      <para>Break the warnings by installing parallel port
              hardware that uses irq 7 and the PPP driver for it (this
              happens on most systems), and install an ide drive or
              other hardware that uses irq 15 and a suitable driver
              for it.</para>
	    </listitem>
	  </itemizedlist>
	</answer>
      </qandaentry>

      <qandaentry>
        <question id="file-table-full">
          <para>Why does <errorname>file: table is full</errorname> show up
            repeatedly in dmesg?</para>
        </question>
        <answer>
          <para>
            This error message indicates you have exhausted the number
            of available file descriptors on your system.  Please see
            the <ulink
            url="../handbook/configtuning-kernel-limits.html#KERN-MAXFILES">kern.maxfiles
            </ulink>section of the <ulink
            url="../handbook/configtuning-kernel-limits.html">Tuning
            Kernel Limits</ulink> section of the Handbook for a
            discussion and solution.</para>
        </answer>
      </qandaentry>

      <qandaentry>
	<question id="laptop-clock-skew">
	  <para>Why does the clock on my laptop keep incorrect time?</para>
	</question>

	<answer>
	  <para>Your laptop has two or more clocks, and FreeBSD has chosen to
	    use the wrong one.</para>

	  <para>Run &man.dmesg.8;, and check for lines that contain
	    <literal>Timecounter</literal>.  The last line printed is the one
	    that FreeBSD chose, and will almost certainly be
	    <literal>TSC</literal>.</para>

	  <screen>&prompt.root; <userinput>dmesg | grep Timecounter</userinput>
Timecounter "i8254"  frequency 1193182 Hz
Timecounter "TSC"  frequency 595573479 Hz</screen>

	  <para>You can confirm this by checking the
	    <varname>kern.timecounter.hardware</varname>
	      &man.sysctl.3;.</para>

	  <screen>&prompt.root; <userinput>sysctl kern.timecounter.hardware</userinput>
kern.timecounter.hardware: TSC</screen>
	
	  <para>The BIOS may modify the TSC clock&mdash;perhaps to change the
	    speed of the processor when running from batteries, or going in to
	    a power saving mode, but FreeBSD is unaware of these adjustments,
	    and appears to gain or lose time.</para>

	  <para>In this example, the <literal>i8254</literal> clock is also
	    available, and can be selected by writing its name to the
	    <varname>kern.timecounter.hardware</varname>
	      &man.sysctl.3;.</para>

	  <screen>&prompt.root; <userinput>sysctl -w kern.timecounter.hardware=i8254</userinput>
kern.timecounter.hardware: TSC -&gt; i8254</screen>

	  <para>Your laptop should now start keeping more accurate
	    time.</para>

	  <para>To have this change automatically run at boot time, add the
	    following line to <filename>/etc/sysctl.conf</filename>.</para>

	  <programlisting>kern.timecounter.hardware=i8254</programlisting>
	</answer>
      </qandaentry>

      <qandaentry>
        <question id="boot-read-error">
          <para>Why does FreeBSD's boot loader display
            <errorname>Read error</errorname> and stop after the BIOS
            screen?</para>
        </question>

        <answer>
          <para>FreeBSD's boot loader is incorrectly recognizing the hard 
            drive's geometry. This must be manually set within fdisk when 
            creating or modifying FreeBSD's slice.
          </para>
          <para>The correct drive geometry values can be found within the
            machine's BIOS. Look for the number of cylinders, heads and
            sectors for the particular drive.
          </para>
          <para>Within &man.sysinstall.8;'s fdisk, hit 
            <keycap>G</keycap> to set the drive geometry.</para>
          <para>A dialog will pop up requesting the number of cylinders, heads
            and sectors.  Type the numbers found from the BIOS separates by
            forward slashes.
          </para>
          <para>5000 cylinders, 250 sectors and 60 sectors would be entered as
            <userinput>5000/250/60</userinput>
          </para>
          <para>Press enter to set the values, and hit
          <keycap>W</keycap> to write the
          new partition table to the drive.
          </para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="bootmanager-restore">
          <para>Another operating system destroyed my Boot Manager.  How do I 
            get it back?
          </para>
        </question>

        <answer>
          <para>Enter &man.sysinstall.8; and choose Configure,
            then Fdisk.  Select the disk the Boot Manager resided on
            with the <keycap>space</keycap> key.  Press 
            <keycap>W</keycap> to write changes to the drive.  A prompt
            will appear asking which boot loader to install.  Select this,
            and it will be restored.
          </para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="indefinite-wait-buffer">
          <para>What does the error <errorname>swap_pager: indefinite
            wait buffer:</errorname> mean?</para>
        </question>

        <answer>
          <para>This means that a process is trying to page memory to
            disk, and the page attempt has hung trying to access the
            disk for more than 20 seconds.  It might be caused by bad
            blocks on the disk drive, disk wiring, cables, or any
            other disk I/O-related hardware.  If the drive itself is
            actually bad, you will also see disk errors in
            <filename>/var/log/messages</filename> and in the output
            of <command>dmesg</command>.  Otherwise, check your cables
            and connections.</para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="commercial">
    <title>Commercial Applications</title>

      <note>
        <para>This section is still very sparse, though we are hoping, of
          course, that companies will add to it! :) The FreeBSD group has
          no financial interest in any of the companies listed here but
          simply lists them as a public service (and feels that commercial
          interest in FreeBSD can have very positive effects on FreeBSD's
          long-term viability). We encourage commercial software vendors to
          send their entries here for inclusion. See <ulink
          URL="../../../../commercial/index.html">the
          Vendors page</ulink> for a longer list.</para>
      </note>

    <qandaset>
      <qandaentry>
        <question id="officesuite">
          <para>Where can I get an Office Suite for FreeBSD?</para>
        </question>
        <answer>
	  <itemizedlist>
  	    <listitem>
	      <para><ulink url="http://www.freebsdmall.com/">The FreeBSD Mall</ulink>
                offers a FreeBSD native version of <ulink
                url="http://www.vistasource.com/">VistaSource</ulink>
                ApplixWare 5.</para>
	
	      <para>ApplixWare is a rich full-featured, commercial
	        Office Suite for FreeBSD containing a word processor,
	        spreadsheet, presentation program, vector drawing
	        package, and other applications.
		</para>

	      <para>ApplixWare is offered as part of the FreeBSD Mall's BSD
		Desktop Edition.</para>

  	    </listitem>
	    <listitem>
	      <para>The Linux version of <ulink
	        url="http://www.sun.com/staroffice/">StarOffice</ulink>
	        works flawlessly on FreeBSD.  The easiest way to
	        install the Linux version of StarOffice is through the
	        <ulink
	        url="../handbook/ports.html">FreeBSD
	        Ports collection</ulink>.  Future versions of the
	        open-source <ulink
	        url="http://www.openoffice.org/">OpenOffice</ulink>
	        suite should work as well.</para>
	    </listitem>
	  </itemizedlist>
        </answer>
      </qandaentry>
      <qandaentry>
        <question id="motif">
          <para>Where can I get Motif for FreeBSD?</para>
        </question>

        <answer>
	  <para>The Open Group has released the source code to Motif 2.1.30.
	    You can install the <literal>open-motif</literal> package, or
	    compile it from ports.  Refer to
	    <ulink url="../handbook/ports.html">the ports section of the
	      Handbook</ulink> for more information on how to do this.

	    <note>
	      <para>The Open Motif distribution only allows redistribution
		if it is running on an <ulink url="http://www.opensource.org/">
		  open source</ulink> operating system.</para>
	    </note>
	  </para>

          <para>In addition, there are commercial distributions of the Motif
            software available.  These, however, are not for free, but their
            license allows them to be used in closed-source software.
	    Contact <link linkend="apps2go">Apps2go</link> for the
            least expensive ELF Motif 2.1.20 distribution for FreeBSD
            (either i386 or Alpha).<anchor id="apps2go"></para>

          <para>There are two distributions, the <quote>developement
            edition</quote> and the <quote>runtime edition</quote> (for
            much less).  These distributions includes:</para>

            <itemizedlist>
              <listitem>
                <para>OSF/Motif manager, xmbind, panner, wsm.</para>
              </listitem>

              <listitem>
                <para>Development kit with uil, mrm, xm, xmcxx, include
                  and Imake files.</para>
              </listitem>

              <listitem>
                <para>Static and dynamic ELF libraries (for use with
                  FreeBSD 3.0 and above).</para>
              </listitem>

              <listitem>
                <para>Demonstration applets.</para>
              </listitem>
            </itemizedlist>

          <para>Be sure to specify that you want the FreeBSD version of
            Motif when ordering (do not forget to mention the architecture
            you want too)! Versions for NetBSD and OpenBSD are also sold by
            <emphasis>Apps2go</emphasis>. This is currently a FTP only
            download.</para>

            <variablelist>
              <varlistentry>
                <term>More info</term>
                <listitem>
                  <para><ulink URL="http://www.apps2go.com/">
                    Apps2go WWW page</ulink></para>
                </listitem>
              </varlistentry>

              <varlistentry>
                <term>or</term>
                  <listitem>
                    <para>
                      <email>sales@apps2go.com</email> or
                      <email>support@apps2go.com</email>
                      </para>
                  </listitem>
                </varlistentry>

                <varlistentry>
                  <term>or</term>
                  <listitem>
                    <para>phone (817) 431 8775  or +1 817 431-8775</para>
                  </listitem>
                </varlistentry>
              </variablelist>

          <para>Contact <link linkend="metrox">Metro Link</link>
            for an either ELF or a.out Motif 2.1 distribution for
            FreeBSD.</para>

          <para>This distribution includes:</para>
            <itemizedlist>
              <listitem>
                <para>OSF/Motif manager, xmbind, panner, wsm.</para>
              </listitem>

              <listitem>
                <para>Development kit with uil, mrm, xm, xmcxx, include
                  and Imake files.</para>
              </listitem>

              <listitem>
                <para>Static and dynamic libraries (specify ELF for use
                  with FreeBSD 3.0 and later; or a.out for use with FreeBSD
                  2.2.8 and earlier).</para>
              </listitem>

              <listitem>
                <para>Demonstration applets.</para>
              </listitem>

              <listitem>
              <para>Preformatted man pages.</para>
              </listitem>

              </itemizedlist>

          <para>Be sure to specify that you want the FreeBSD version
            of Motif when ordering! Versions for Linux are also sold by
            <emphasis>Metro Link</emphasis>. This is available on either a
            CDROM or for FTP download.</para>

          <para>Contact <link linkend="xig">Xi Graphics</link> for an
            a.out Motif 2.0 distribution for FreeBSD.</para>

          <para>This distribution includes:</para>
            <itemizedlist>
              <listitem>
                <para>OSF/Motif manager, xmbind, panner, wsm.</para>
              </listitem>

              <listitem>
                <para>Development kit with uil, mrm, xm, xmcxx, include
                  and Imake files.</para>
              </listitem>

              <listitem>
                <para>Static and dynamic libraries (for use with FreeBSD
                  2.2.8 and earlier).</para>
              </listitem>

              <listitem>
                <para>Demonstration applets.</para>
              </listitem>

              <listitem>
                <para>Preformatted man pages.</para>
              </listitem>
            </itemizedlist>

          <para>Be sure to specify that you want the FreeBSD version
            of Motif when ordering! Versions for BSDI and Linux are also
            sold by <emphasis>Xi Graphics</emphasis>. This is currently a 4
            diskette set... in the future this will change to a unified CD
            distribution like their CDE.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="cde">
          <para>Where can I get CDE for FreeBSD?</para>
        </question>

        <answer>
          <para><link linkend="xig">Xi Graphics</link> used to sell CDE
            for FreeBSD, but no longer do.</para>

          <para><ulink URL="http://www.kde.org/">KDE</ulink> is an open
            source X11 desktop which is similar to CDE in many respects.
            You might also like the look and feel of <ulink
            URL="http://www.xfce.org/">xfce</ulink>. KDE and xfce are both
            in the <ulink URL="../../../../ports/index.html">ports
            system</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="commercial-xserver">
          <para>Are there any commercial high-performance X servers?</para>
        </question>

        <answer>
          <para>Yes, <ulink URL="http://www.xig.com/">Xi Graphics</ulink>
            and <ulink URL="http://www.metrolink.com/">Metro Link</ulink>
            sell Accelerated-X product for FreeBSD and other Intel based
            systems.</para>

          <para>The Metro Link offering is a high performance X Server
            that offers easy configuration using the FreeBSD Package suite
            of tools, support for multiple concurrent video boards and is
            distributed in binary form only, in a convenient FTP download.
            Not to mention the Metro Link offering is available at the very
            reasonable price of $39. <anchor id="metrox"></para>

          <para>Metro Link also sells both ELF and a.out Motif for
            FreeBSD (see above).</para>

            <variablelist>
              <varlistentry>
                <term>More info</term>
                <listitem>
                  <para><ulink URL="http://www.metrolink.com/">
                    Metro Link WWW page</ulink></para>
                </listitem>
              </varlistentry>

              <varlistentry>
                <term>or</term>
                <listitem>
                  <para><email>sales@metrolink.com</email>
                    or <email>tech@metrolink.com</email>
                    </para>
                </listitem>
              </varlistentry>

              <varlistentry>
                <term>or</term>
                  <listitem>
                    <para>phone (954) 938-0283  or +1 954 938-0283</para>
                  </listitem>
                </varlistentry>
              </variablelist>

          <para>The Xi Graphics offering is a high performance X Server
            that offers easy configuration, support for multiple concurrent
            video boards and is distributed in binary form only, in a
            unified diskette distribution for FreeBSD and Linux. Xi
            Graphics also offers a high performance X Server tailored for
            laptop support.<anchor id="xig"></para>

          <para>There is a free <quote>compatibility demo</quote> of
            version 5.0 available.</para>

          <para>Xi Graphics also sells Motif and CDE for FreeBSD (see
            above).</para>

            <variablelist>
              <varlistentry>
                <term>More info</term>
                <listitem>
                  <para><ulink URL="http://www.xig.com/">
                    Xi Graphics WWW page</ulink></para>
                </listitem>
              </varlistentry>

              <varlistentry>
                <term>or</term>
                  <listitem>
                    <para><email>sales@xig.com</email>
                      or <email>support@xig.com</email>
                      </para>
                  </listitem>
                </varlistentry>

                <varlistentry>
                  <term>or</term>
                  <listitem>
                    <para>phone (800) 946 7433  or +1 303 298-7478.</para>
                  </listitem>
                </varlistentry>
              </variablelist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="database-systems">
          <para>Are there any Database systems for FreeBSD?</para>
        </question>

        <answer>
          <para>Yes! See the <ulink
            URL="../../../../commercial/software_bycat.html#CATEGORY_DATABASE">
            Commercial Vendors</ulink> section of FreeBSD's Web site.</para>

          <para>Also see the <ulink
            URL="../../../../ports/databases.html">
            Databases</ulink> section of the Ports collection.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="oracle-support">
          <para>Can I run Oracle on FreeBSD?</para>
        </question>

        <answer>
          <para>Yes. The following pages tell you exactly how to setup
            Linux-Oracle on FreeBSD:</para>

            <itemizedlist>
              <listitem>
                <para><ulink
                  URL="http://www.scc.nl/~marcel/howto-oracle.html">
                  http://www.scc.nl/~marcel/howto-oracle.html</ulink></para>
              </listitem>

              <listitem>
                <para><ulink
                  URL="http://www.lf.net/lf/pi/oracle/install-linux-oracle-on-freebsd">

                  http://www.lf.net/lf/pi/oracle/install-linux-oracle-on-freebsd</ulink></para>

              </listitem>
            </itemizedlist>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="applications">
    <title>User Applications</title>

    <qandaset>
      <qandaentry>
        <question id="user-apps">
          <para>So, where are all the user applications?</para>
        </question>

        <answer>
          <para>Please take a look at
            <ulink URL="../../../../ports/index.html">the ports
            page</ulink> for info on software packages ported to FreeBSD.
            The list currently tops &os.numports; and is growing daily, so come back
            to check often or subscribe to the
            <literal>freebsd-announce</literal> <link
            linkend="mailing">mailing list</link> for periodic updates on
            new entries.</para>

          <para>Most ports should be available for the 2.2, 3.x and 4.x
            branches, and many of them should work on 2.1.x systems as
            well. Each time a FreeBSD release is made, a snapshot of the
            ports tree at the time of release in also included in the
            <filename>ports/</filename> directory.</para>

          <para>We also support the concept of a <quote>package</quote>,
            essentially no more than a gzipped binary distribution with a
            little extra intelligence embedded in it for doing whatever
            custom installation work is required. A package can be
            installed and uninstalled again easily without having to know
            the gory details of which files it includes.</para>

          <para>Use the package installation menu in
            <filename>/stand/sysinstall</filename> (under the
            post-configuration menu item) or invoke the
            &man.pkg.add.1; command on the specific package
            files you are interested in installing. Package files can
            usually be identified by their <filename>.tgz</filename> suffix
            and CDROM distribution people will have a
            <filename>packages/All</filename> directory on their CD which
            contains such files. They can also be downloaded over the net
            for various versions of FreeBSD at the following
            locations:</para>

            <variablelist>
              <varlistentry>
                <term>for 2.2.8-RELEASE/2.2.8-STABLE</term>
                <listitem>
                  <para><ulink
                    URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-2.2.8/">
                    ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-2.2.8/</ulink></para>
                </listitem>
              </varlistentry>

              <varlistentry>
                <term>for 3.X-RELEASE/3.X-STABLE</term>
                <listitem>
                  <para><ulink
                    URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-3-stable/">
                    ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-3-stable/</ulink></para>
                </listitem>
              </varlistentry>

              <varlistentry>
                <term>for 4.X-RELEASE/4-STABLE</term>
                <listitem>
                  <para><ulink
                    URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/">
                    ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/</ulink></para>

                </listitem>
              </varlistentry>

              <varlistentry>
                <term>for 5.X-CURRENT</term>
                <listitem>
                  <para><ulink
                    URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current/">
                    ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current</ulink></para>
                </listitem>
              </varlistentry>
            </variablelist>

          <para>or your nearest local mirror site.</para>

          <para>Note that all ports may not be available as packages since
            new ones are constantly being added. It is always a good idea
            to check back periodically to see which packages are available
            at the <ulink
            URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/">ftp.FreeBSD.org</ulink>
            master site.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="missing-libcso30">
          <para>Where do I find libc.so.3.0?</para>
        </question>

        <answer>
          <para>You are trying to run a package built on 2.2 and later on
            a 2.1.x system. Please take a look at the previous section and
            get the correct port/package for your system.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="missing-libcso40">
          <para>Why do I get a message reading <errorname>Error: can't find
            libc.so.4.0</errorname>?</para>
        </question>

        <answer>

          <para>You accidently downloaded packages meant for 4.X and 5.X
            systems and attempted to install them on your 2.X or 3.X
            FreeBSD system. Please download the correct version of the
            packages.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="emul">
           <para>Why does ghostscript give lots of errors with my
              386/486SX?</para>
        </question>

        <answer>
          <para>You do not have a math co-processor, right?
            You will need to add the alternative math emulator to your
            kernel; you do this by adding the following to your kernel
            config file and it will be compiled in.</para>

          <programlisting>options GPL_MATH_EMULATE</programlisting>

            <note>
              <para>You will need to remove the
                <literal>MATH_EMULATE</literal> option when you do
                this.</para>
            </note>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="sco-socksys">
          <para>Why do SCO/iBCS2 applications bomb on
            <errorname>socksys</errorname>?  (FreeBSD 3.0 and older only).</para>
        </question>

        <answer>
          <para>You first need to edit the
            <filename>/etc/sysconfig</filename> (or
            <filename>/etc/rc.conf</filename>, see &man.rc.conf.5;) file in the last section to change the
            following variable to <literal>YES</literal>:</para>

          <programlisting># Set to YES if you want ibcs2 (SCO) emulation loaded at startup
ibcs2=NO</programlisting>

          <para>It will load the ibcs2 kernel module at startup.</para>

          <para>You will then need to set up /compat/ibcs2/dev to look
            like:</para>

          <screen>lrwxr-xr-x  1 root  wheel         9 Oct 15 22:20 X0R@ -&gt; /dev/null
lrwxr-xr-x  1 root  wheel         7 Oct 15 22:20 nfsd@ -&gt; socksys
-rw-rw-r--  1 root  wheel         0 Oct 28 12:02 null
lrwxr-xr-x  1 root  wheel         9 Oct 15 22:20 socksys@ -&gt; /dev/null
crw-rw-rw-  1 root  wheel   41,   1 Oct 15 22:14 spx</screen>

          <para>You just need socksys to go to
            <devicename>/dev/null</devicename> (see &man.null.4;)
            to fake the open &amp; close. The code in -CURRENT will handle
            the rest. This is much cleaner than the way it was done before.
            If you want the <devicename>spx</devicename> driver for a local
            socket X connection, define <literal>SPX_HACK</literal> when
            you compile the system.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="configure-inn">
          <para>How do I configure INN (Internet News) for my machine?</para>
        </question>

        <answer>
          <para>After installing the <filename role="package">news/inn</filename> package or port, an excellent
            place to start is <ulink
            URL="http://www.cis.ohio-state.edu/~barr/INN.html">Dave Barr's
            INN Page</ulink> where you will find the INN FAQ.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ms-frontpage">
          <para>What version of Microsoft FrontPage should I get?</para>
        </question>

        <answer>
          <para>Use the Port, Luke!  A pre-patched version of Apache,
            <filename role="package">apache13-fp</filename>, is available in the ports
            tree.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="java">
          <para>Does FreeBSD support Java?</para>
        </question>

        <answer>
          <para>Yes. Please see <ulink
            URL="../../../../java/index.html">
            http://www.FreeBSD.org/java/</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ports-3x">
          <para>Why can I not build this port on my 3.X-STABLE machine?</para>
        </question>

        <answer>
          <para>If you are running a FreeBSD version that lags
            significantly behind -CURRENT or -STABLE, you may need a ports
            upgrade kit from <ulink URL="../../../../ports/index.html">
            http://www.FreeBSD.org/ports/</ulink>. If you are up to date,
            then someone might have committed a change to the port which
            works for -CURRENT but which broke the port for -STABLE. Please
            submit a bug report on this with the
            &man.send-pr.1; command, since the ports
            collection is supposed to work for both the -CURRENT and
            -STABLE branches.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="find-ldso">
          <para>Where do I find ld.so?</para>
        </question>

        <answer>
          <para>a.out applications like Netscape Navigator require
            a.out libraries.  A version of FreeBSD built with ELF
            libraries does not install them by default.  You will get
            complaints about not having
            <filename>/usr/libexec/ld.so</filename> if this is the
            case on your system.  These libraries are available as an
            add-on in the compat22 distribution.  Use
            &man.sysinstall.8; to install them.  You can
            also install them from the FreeBSD source code:</para>

          <screen>&prompt.root; <userinput>cd /usr/src/lib/compat/compat22</userinput>
&prompt.root; <userinput>make install clean</userinput></screen>

          <para>If you want to install the latest compat22 libraries
            whenever you run <command>make world</command>, edit
            <filename>/etc/make.conf</filename> to include
            <varname>COMPAT22=YES</varname>.  Old compatability
            libraries change rarely, if ever, so this is not generally
            needed.</para>

          <para>Also see the ERRATAs for 3.1-RELEASE and
            3.2-RELEASE.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ports-update">
           <para>I updated the sources, now how do I update my installed
             ports?</para>
        </question>

        <answer>
          <para>FreeBSD does not include a port upgrading tool, but it
            does have some tools to make the upgrade process somewhat
            easier.  You can also install additional tools to simplify
            port handling.</para>

          <para>The &man.pkg.version.1; command can generate a script
            that will update installed ports to the latest version in
            the ports tree.</para>

          <screen>&prompt.root; <userinput>pkg_version <option>-c</option> > <replaceable>/tmp/myscript</replaceable></userinput></screen>

          <para>The output script <emphasis>must</emphasis> be edited by
            hand before you use it. Current versions of
            &man.pkg.version.1; force this by inserting an
            &man.exit.1; at the beginning of the script.</para>

          <para>You should save the output of the script, as it will note
            packages that depend on the one that has been updated. These
            may or may not need to be updated as well. The usual case where
            they need to be updated is that a shared library has changed
            version numbers, so the ports that used that library need to be
            rebuilt to use the new version.</para>

          <para>If you have the disk space, you can use the
            <command>portupgrade</command> tool to automate all of
            this.  <command>portupgrade</command> includes various
            tools to simplify package handling.  It is available under
            <filename role="package">sysutils/portupgrade</filename>.
            Since it is written in Ruby,
            <command>portupgrade</command> is an unlikely candidate for
            integration with the main FreeBSD tree.  That should not
            stop anyone from using it, however.</para>

          <para>If your system is up full time, the &man.periodic.8 system
            can be used to generate a weekly list of ports that might need
            updating by setting
            <literal>weekly_status_pkg_enable="YES"</literal> in
            <filename>/etc/periodic.conf</filename>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="minimal-sh">
          <para>Why is <command>/bin/sh</command> so minimal?  Why does
            FreeBSD not use <command>bash</command> or another shell?</para>
        </question>

        <answer>
          <para>Because POSIX says that there shall be such a shell.</para>

          <para>The more complicated answer: many people need to write shell
            scripts which will be portable across many systems. That is why
            POSIX specifies the shell and utility commands in great detail.
            Most scripts are written in Bourne shell, and because several
            important programming interfaces (&man.make.1;, &man.system.3;,
            &man.popen.3;, and analogues in higher-level scripting
            languages like Perl and Tcl) are specified to use the Bourne
            shell to interpret commands. Because the Bourne shell is so
            often and widely used, it is important for it to be quick to
            start, be deterministic in its behavior, and have a small
            memory footprint.</para>

          <para>The existing implementation is our best effort at meeting as
            many of these requirements simultaneously as we can. In order to
            keep <command>/bin/sh</command> small, we have not provided many
            of the convenience features that other shells have. That is why the
            Ports Collection includes more featureful shells like bash, scsh,
            tcsh, and zsh.  (You can compare for yourself the memory
            utilization of all these shells by looking at the
            <quote>VSZ</quote> and <quote>RSS</quote> columns in a <command>ps
              -u</command> listing.)</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="netscape-slow-startup">
          <para>Why do Netscape and Opera take so long to
            start?</para>
        </question>

        <answer>
          <para>The usual answer is that DNS on your system is
            misconfigured.  Both Netscape and Opera perform DNS checks
            when starting up.  The browser will not appear on your
            desktop until the program either gets a response or
            determines that the system has no network
            connection.</para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="kernelconfig">
    <title>Kernel Configuration</title>

    <qandaset>
      <qandaentry>
        <question id="make-kernel">
          <para>I would like to customize my kernel. Is it difficult?</para>
        </question>

        <answer>
          <para>Not at all! Check out the <ulink
            URL="../handbook/kernelconfig.html">
            kernel config section of the Handbook</ulink>.</para>

            <note>
	      <para>We recommend that you make a dated snapshot of
	        your new <filename>/kernel</filename> called
	        <filename>/kernel.YYMMDD</filename> after you get it
	        working properly.  Also back up your new
	        <filename>/modules</filename> directory to
	        <filename>/modules.YYMMDD</filename>.  That way, if
	        you make a mistake the next time you play with your
	        configuration you can boot the backup kernel instead
	        of having to fall back to
	        <filename>kernel.GENERIC</filename>. This is
	        particularly important if you are now booting from a
	        controller that GENERIC does not support.</para>
            </note>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="missing-hw-float">
          <para>My kernel compiles fail because
            <literal>_hw_float</literal> is missing.  How do I solve
            this problem?</para>
        </question>

        <answer>
          <para>Let me guess. You removed
            <devicename>npx0</devicename> (see &man.npx.4;)
            from your kernel configuration file because you do not have a
            math co-processor, right? Wrong! :-) The
            <devicename>npx0</devicename> is
            <emphasis>MANDATORY</emphasis>. Even if you do not have a
            mathematic co-processor, you <emphasis>must</emphasis>
            include the <devicename>npx0</devicename> device.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="why-kernel-big">
          <para>Why is my kernel so big (over 10MB)?</para>
        </question>

        <answer>
          <para>Chances are, you compiled your kernel in
            <emphasis>debug mode</emphasis>.  Kernels built in debug
            mode contain many symbols that are used for debugging, thus
            greatly increasing the size of the kernel.  Note that if you
            running a FreeBSD 3.0 or later system, there will be little
            or no performance decrease from running a debug kernel,
            and it is useful to keep one around in case of a system
            panic.</para>

          <para>However, if you are running low on disk space, or
            you simply do not want to run a debug kernel, make sure
            that both of the following are true:</para>

          <itemizedlist>
            <listitem>
              <para>You do not have a line in your kernel
                configuration file that reads:</para>

              <programlisting>makeoptions DEBUG=-g</programlisting>
            </listitem>

            <listitem>
              <para>You are not running &man.config.8; with
                the <option>-g</option> option.</para>
            </listitem>
          </itemizedlist>

          <para>Both of the above situations will cause your kernel to
            be built in debug mode.  As long as you make sure you follow
            the steps above, you can build your kernel normally, and you
            should notice a fairly large size decrease; most kernels
            tend to be around 1.5MB to 2MB.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="multiport-serial-interrupts">
          <para>Why do I get interrupt conflicts with multi-port serial
            code?</para>
        </question>

        <answer>
          <para>When I compile a kernel
            with multi-port serial code, it tells me that only the first
            port is probed and the rest skipped due to interrupt conflicts.
            How do I fix this?</para>

          <para>The problem here is that
            FreeBSD has code built-in to keep the kernel from getting
            trashed due to hardware or software conflicts. The way to fix
            this is to leave out the IRQ settings on all but one port. Here
            is a example:</para>

          <programlisting>#
# Multiport high-speed serial line - 16550 UARTS
#
device sio2 at isa? port 0x2a0 tty irq 5 flags 0x501 vector siointr
device sio3 at isa? port 0x2a8 tty flags 0x501 vector siointr
device sio4 at isa? port 0x2b0 tty flags 0x501 vector siointr
device sio5 at isa? port 0x2b8 tty flags 0x501 vector siointr</programlisting>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="generic-kernel-build-failure">
          <para>Why does every kernel I try to build fail to compile, even
            GENERIC?</para>
        </question>

        <answer>
          <para>There are a number of possible causes for this problem.
            They are, in no particular order:</para>

          <itemizedlist>
            <listitem>
              <para>You are not using the new <command>make
                buildkernel</command> and <command>make
                installkernel</command> targets, and your source tree is
                different from the one used to build the currently running
                system (e.g., you are compiling 4.3-RELEASE on a 4.0-RELEASE
                system).  If you are attempting an upgrade, please read the
                <filename>/usr/src/UPDATING</filename> file, paying
                particular attention to the <quote>COMMON ITEMS</quote>
                section at the end.</para>
            </listitem>

            <listitem>
              <para>You are using the new <command>make
                buildkernel</command> and <command>make
                installkernel</command> targets, but you failed to assert
                the completion of the <command>make buildworld</command>
                target.  The <command>make buildkernel</command> target
                relies on files generated by the <command>make
                buildworld</command> target to complete its job
                correctly.</para>
            </listitem>

            <listitem>
              <para>Even if you are trying to build <link
                linkend="stable">FreeBSD-STABLE</link>, it is possible that
                you fetched the source tree at a time when it was either
                being modified, or broken for other reasons; only releases
                are absolutely guaranteed to be buildable, although <link
                linkend="stable">FreeBSD-STABLE</link> builds fine the
                majority of the time.  If you have not already done so, try
                re-fetching the source tree and see if the problem goes
                away.  Try using a different server in case the one you are
                using is having problems.</para>
            </listitem>
          </itemizedlist>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="disks">
    <title>Disks, Filesystems, and Boot Loaders</title>

    <qandaset>
      <qandaentry>
        <question id="adding-disks">
          <para>How can I add my new hard disk to my FreeBSD system?</para>
        </question>

        <answer>
          <para>See the Disk Formatting Tutorial at <ulink
            URL="../../articles/formatting-media/index.html">
            www.FreeBSD.org</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="new-huge-disk">
          <para>How do I move my system over to my huge new disk?</para>
        </question>

        <answer>
          <para>The best way is to reinstall the OS on the new
            disk, then move the user data over.  This is highly
            recommended if you have been tracking -stable for more
            than one release, or have updated a release instead of
            installing a new one.  You can install booteasy on both
            disks with &man.boot0cfg.8;, and dual boot them until
            you are happy with the new configuration.  Skip the
            next paragraph to find out how to move the data after
            doing this.</para>

          <para>Should you decide not to do a fresh install, you
            need to partition and label the new disk with either
            <filename>/stand/sysinstall</filename>, or &man.fdisk.8;
            and &man.disklabel.8;.  You should also install booteasy
            on both disks with &man.boot0cfg.8;, so that you can
            dual boot to the old or new system after the copying
            is done.  See the <ulink
            url="../../articles/formatting-media/index.html">
            formatting-media article</ulink> for details on this
            process.</para>

          <para>Now you have the new disk set up, and are ready
            to move the data.  Unfortunately, you cannot just blindly
            copy the data.  Things like device files (in
	    <filename>/dev</filename>), flags, and links tend to
            screw that up.  You need to use tools that understand
            these things, which means &man.dump.8;.
            Although it is suggested that you move the data in single user
            mode, it is not required.</para>

          <para>You should never use anything but &man.dump.8; and
            &man.restore.8; to move the root file system.  The
            &man.tar.1; command may work - then again, it may not.
            You should also use &man.dump.8; and &man.restore.8;
            if you are moving a single partition to another empty
            partition.  The sequence of steps to use dump to move
            a partitions data to a new partition is:</para>

          <procedure>
            <step>
              <para>newfs the new partition.</para>
            </step>

            <step>
              <para>mount it on a temporary mount point.</para>
            </step>

            <step>
              <para>cd to that directory.</para>
            </step>

            <step>
              <para>dump the old partition, piping output to the
                new one.</para>
            </step>
          </procedure>

          <para>For example, if you are going to move root to
            <devicename>/dev/ad1s1a</devicename>, with
            <filename>/mnt</filename> as the temporary mount point,
            it is:</para>

          <screen>&prompt.root; <userinput>newfs /dev/ad1s1a</userinput>
&prompt.root; <userinput>mount /dev/ad1s1a /mnt</userinput>
&prompt.root; <userinput>cd /mnt</userinput>
&prompt.root; <userinput>dump 0af - / | restore xf -</userinput></screen>

          <para>Rearranging your partitions with dump takes a bit more
            work. To merge a partition like <filename>/var</filename>
            into its parent, create the new partition large enough
            for both, move the parent partition as described above,
            then move the child partition into the empty directory
            that the first move created:</para>
	  
          <screen>&prompt.root; <userinput>newfs /dev/ad1s1a</userinput>
&prompt.root; <userinput>mount /dev/ad1s1a /mnt</userinput>
&prompt.root; <userinput>cd /mnt</userinput>
&prompt.root; <userinput>dump 0af - / | restore xf -</userinput>
&prompt.root; <userinput>cd var</userinput>
&prompt.root; <userinput>dump 0af - /var | restore xf -</userinput></screen>

	  <para>To split a directory from its parent, say putting
	    <filename>/var</filename> on its own partition when it was not
	    before, create both partitions, then mount the child partition
	    on the appropriate directory in the temporary mount point, then
	    move the old single partition:</para>

          <screen>&prompt.root; <userinput>newfs /dev/ad1s1a</userinput>
&prompt.root; <userinput>newfs /dev/ad1s1d</userinput>
&prompt.root; <userinput>mount /dev/ad1s1a /mnt</userinput>
&prompt.root; <userinput>mkdir /mnt/var</userinput>
&prompt.root; <userinput>mount /dev/ad1s1d /mnt/var</userinput>
&prompt.root; <userinput>cd /mnt</userinput>
&prompt.root; <userinput>dump 0af - / | restore xf -</userinput></screen>

          <para>You might prefer &man.cpio.1;, &man.pax.1;,
            &man.tar.1; to &man.dump.8; for user data. At the time of
            this writing, these are known to lose file flag information,
            so use them with caution.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="dangerously-dedicated">
          <para>Will a <quote>dangerously dedicated</quote> disk endanger
            my health?</para>
        </question>

        <answer>

          <para><anchor id="dedicate">The installation procedure allows
            you to chose two different methods in partitioning your
            harddisk(s). The default way makes it compatible with other
            operating systems on the same machine, by using fdisk table
            entries (called <quote>slices</quote> in FreeBSD), with a
            FreeBSD slice that employs partitions of its own. Optionally,
            one can chose to install a boot-selector to switch between the
            possible operating systems on the disk(s). The alternative uses
            the entire disk for FreeBSD, and makes no attempt to be
            compatible with other operating systems.</para>

          <para>So why it is called <quote>dangerous</quote>?  A disk in
            this mode does not contain what normal PC utilities would
            consider a valid fdisk table. Depending on how well they have
            been designed, they might complain at you once they are getting
            in contact with such a disk, or even worse, they might damage
            the BSD bootstrap without even asking or notifying you. In
            addition, the <quote>dangerously dedicated</quote> disk's
            layout is known to confuse many BIOSsen, including those from
            AWARD (eg. as found in HP Netserver and Micronics systems as
            well as many others) and Symbios/NCR (for the popular 53C8xx
            range of SCSI controllers). This is not a complete list, there
            are more. Symptoms of this confusion include the <errorname>read
            error</errorname> message printed by the FreeBSD bootstrap when it
            cannot find itself, as well as system lockups when
            booting.</para>

          <para>Why have this mode at all then?  It only saves a few kbytes
            of disk space, and it can cause real problems for a new
            installation. <quote>Dangerously dedicated</quote> mode's
            origins lie in a desire to avoid one of the most common
            problems plaguing new FreeBSD installers - matching the BIOS
            <quote>geometry</quote> numbers for a disk to the disk
            itself.</para>

          <para><quote>Geometry</quote> is an outdated concept, but one
            still at the heart of the PC's BIOS and its interaction with
            disks. When the FreeBSD installer creates slices, it has to
            record the location of these slices on the disk in a fashion
            that corresponds with the way the BIOS expects to find them. If
            it gets it wrong, you will not be able to boot.</para>

          <para><quote>Dangerously dedicated</quote> mode tries to work
            around this by making the problem simpler. In some cases, it
            gets it right. But it is meant to be used as a last-ditch
            alternative - there are better ways to solve the problem 99
            times out of 100.</para>

          <para>So, how do you avoid the need for <quote>DD</quote> mode
            when you are installing? Start by making a note of the geometry
            that your BIOS claims to be using for your disks. You can
            arrange to have the kernel print this as it boots by specifying
            <option>-v</option> at the <literal>boot:</literal> prompt, or
            using <command>boot -v</command> in the loader. Just before the
            installer starts, the kernel will print a list of BIOS
            geometries. Do not panic - wait for the installer to start and
            then use scrollback to read the numbers. Typically the BIOS
            disk units will be in the same order that FreeBSD lists your
            disks, first IDE, then SCSI.</para>

          <para>When you are slicing up your disk, check that the disk
            geometry displayed in the FDISK screen is correct (ie. it
            matches the BIOS numbers); if it is wrong, use the
            <literal>g</literal> key to fix it. You may have to do this if
            there is absolutely nothing on the disk, or if the disk has been
            moved from another system. Note that this is only an issue with
            the disk that you are going to boot from; FreeBSD will sort
            itself out just fine with any other disks you may have.</para>

          <para>Once you have got the BIOS and FreeBSD agreeing about the
            geometry of the disk, your problems are almost guaranteed to be
            over, and with no need for <quote>DD</quote> mode at all. If,
            however, you are still greeted with the dreaded <errorname>read
            error</errorname> message when you try to boot, it is time to cross
            your fingers and go for it - there is nothing left to
            lose.</para>

          <para>To return a <quote>dangerously dedicated</quote> disk
            for normal PC use, there are basically two options. The first
            is, you write enough NULL bytes over the MBR to make any
            subsequent installation believe this to be a blank disk. You
            can do this for example with</para>

          <screen>&prompt.root; <userinput>dd if=/dev/zero of=/dev/rda0 count=15</userinput></screen>

          <para>Alternatively, the undocumented DOS
            <quote>feature</quote></para>

          <screen><prompt>C:\&gt;</prompt> <userinput>fdisk /mbr</userinput></screen>

          <para>will to install a new master boot record as well, thus
            clobbering the BSD bootstrap.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="safe-softupdates">
          <para>Which partitions can safely use softupdates?  I have
            heard that softupdates on <filename>/</filename> can cause
            problems.</para>
        </question>

        <answer>
          <para>Short answer: you can usually use softupdates safely
            on all partitions.</para>

          <para>Long answer: There used to be some concern over using
            softupdates on the root partition.  Softupdates has two
            characteristics that caused this.  First, a softupdates
            partition has a small chance of losing data during a
            system crash.  (The partition will not be corrupted; the
            data will simply be lost.)  Also, softupdates can cause
            temporary space shortages.</para>

          <para>When using softupdates, the kernel can take up to
            thirty seconds to actually write changes to the physical
            disk.  If you delete a large file, the file still resides
            on disk until the kernel actually performs the deletion.
            This can cause a very simple race condition.  Suppose you
            delete one large file and immediately create another large
            file.  The first large file is not yet actually removed
            from the physical disk, so the disk might not have enough
            room for the second large file.  You get an error that the
            partition does not have enough space, although you know
            perfectly well that you just released a large chunk of
            space!  When you try again mere seconds later, the file
            creation works as you expect.  This has left more than one
            user scratching his head and doubting his sanity, the
            FreeBSD filesystem, or both.</para>

          <para>If a system should crash after the kernel accepts a
            chunk of data for writing to disk, but before that data is
            actually written out, data could be lost or corrupted.
            This risk is extremely small, but generally manageable.
            Use of IDE write caching greatly increases this risk; it
            is strongly recommended that you disable IDE write caching
            when using softupdates.</para>

          <para>These issues affect all partitions using softupdates.
            So, what does this mean for the root partition?</para>

          <para>Vital information on the root partition changes very
            rarely.  Files such as <filename>/kernel</filename> and
            the contents of <filename>/etc</filename> only change
            during system maintenance, or when users change their
            passwords.  If the system crashed during the
            thirty-second window after such a change is made, it is
            possible that data could be lost.  This risk is negligible
            for most applications, but you should be aware that it
            exists.  If your system cannot tolerate this much risk,
            do not use softupdates on the root filesystem!</para>

          <para><filename>/</filename> is traditionally one of the
            smallest partitions.  By default, FreeBSD puts the
            <filename>/tmp</filename> directory on
            <filename>/</filename>.  If you have a busy
            <filename>/tmp</filename>, you might see intermittent
            space problems.  Symlinking <filename>/tmp</filename> to
            <filename>/var/tmp</filename> will solve this
            problem.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="inappropriate-ccd">
          <para>What is inappropriate about my ccd?</para>
        </question>

        <answer>
          <para>The symptom of this is:</para>

          <screen>&prompt.root; <userinput>ccdconfig -C</userinput>
ccdconfig: ioctl (CCDIOCSET): /dev/ccd0c: Inappropriate file type or format</screen>

          <para>This usually happens when you are trying to concatenate
            the <literal>c</literal> partitions, which default to type
            <literal>unused</literal>. The ccd driver requires the
            underlying partition type to be FS_BSDFFS. Edit the disklabel
            of the disks you are trying to concatenate and change the types
            of partitions to <literal>4.2BSD</literal>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ccd-disklabel">
          <para>Why can I not edit the disklabel on my ccd?</para>
        </question>

        <answer>
          <para>The symptom of this is:</para>

          <screen>&prompt.root; <userinput>disklabel ccd0</userinput>
(it prints something sensible here, so let us try to edit it)
&prompt.root; <userinput>disklabel -e ccd0</userinput>
(edit, save, quit)
disklabel: ioctl DIOCWDINFO: No disk label on disk;
use "disklabel -r" to install initial label</screen>

          <para>This is because the disklabel returned by ccd is actually
            a <quote>fake</quote> one that is not really on the disk.
            You can solve this problem by writing it back explicitly,
            as in:</para>

          <screen>&prompt.root; <userinput>disklabel ccd0 &gt; /tmp/disklabel.tmp</userinput>
&prompt.root; <userinput>disklabel -Rr ccd0 /tmp/disklabel.tmp</userinput>
&prompt.root; <userinput>disklabel -e ccd0</userinput>
(this will work now)</screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="mount-foreign-fs">
          <para>Can I mount other foreign filesystems under FreeBSD?</para>
        </question>

        <answer>
          <variablelist>
            <varlistentry>
              <term>Digital UNIX</term>

              <listitem>
                <para>UFS CDROMs can be mounted directly on FreeBSD.
                  Mounting disk partitions from Digital UNIX and other
                  systems that support UFS may be more complex, depending
                  on the details of the disk partitioning for the operating
                  system in question.</para>
              </listitem>
            </varlistentry>

            <varlistentry>
              <term>Linux</term>

              <listitem>
                <para>As of 2.2, FreeBSD supports <literal>ext2fs</literal>
                  partitions.  See &man.mount.ext2fs.8; for more
                  information.</para>
              </listitem>
            </varlistentry>

            <varlistentry>
              <term>NT</term>

              <listitem>
                <para>A read-only NTFS driver exists for FreeBSD. For more
                  information, see this tutorial by Mark Ovens at <ulink
                  URL="http://ukug.uk.FreeBSD.org/~mark/ntfs_install.html">
                  http://ukug.uk.FreeBSD.org/~mark/ntfs_install.html</ulink>.
                  </para>
              </listitem>
            </varlistentry>
          </variablelist>

          <para>Any other information on this subject would be
            appreciated.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="mount-dos">
          <para>How do I mount a secondary DOS partition?</para>
        </question>

        <answer>

        <para>The secondary DOS partitions are found after ALL the primary
          partitions. For example, if you have an <quote>E</quote>
          partition as the second DOS partition on the second SCSI drive,
          you need to create the special files for <quote>slice 5</quote>
          in /dev, then mount /dev/da1s5:</para>

        <screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>sh MAKEDEV da1s5</userinput>
&prompt.root; <userinput>mount -t msdos /dev/da1s5 /dos/e</userinput></screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="crypto-filesystem">
          <para>Is there a cryptographic filesystem for &os;?</para>
        </question>

        <answer>
          <para>Yes; see the <filename role="package">security/cfs</filename> port.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="nt-bootloader">
          <para>How can I use the NT loader to boot FreeBSD?</para>
        </question>

        <answer>
          <para>This procedure is slightly different for 2.2.x and 3.x
            (with the 3-stage boot) systems.</para>

          <para>The general idea is that you copy the first sector of your
            native root FreeBSD partition into a file in the DOS/NT
            partition. Assuming you name that file something like
            <filename>c:\bootsect.bsd</filename> (inspired by
            <filename>c:\bootsect.dos</filename>), you can then edit the
            <filename>c:\boot.ini</filename> file to come up with something
            like this:</para>

          <programlisting>[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows NT"
C:\BOOTSECT.BSD="FreeBSD"
C:\="DOS"</programlisting>

          <para>For 2.2.x systems this procedure assumes that DOS, NT,
            FreeBSD, or whatever have been installed into their respective
            fdisk partitions on the <emphasis>same</emphasis>
            disk.  This example was tested on a system where DOS &amp; NT
            were on the first fdisk partition, and FreeBSD on the second.
            FreeBSD was also set up to boot from its native partition, not
            the disk's MBR.</para>

          <para>Mount a DOS-formatted floppy (if you have converted to NTFS)
            or the FAT partition, under, say,
            <filename>/mnt</filename>.</para>

          <screen>&prompt.root; <userinput>dd if=/dev/rda0a of=/mnt/bootsect.bsd bs=512 count=1</userinput></screen>

          <para>Reboot into DOS or NT.  NTFS users copy the
            <filename>bootsect.bsd</filename> and/or the
            <filename>bootsect.lnx</filename> file from the floppy to
            <filename>C:\</filename>. Modify the attributes (permissions)
            on <filename>boot.ini</filename> with:</para>

          <screen><prompt>C:\&gt;</prompt> <userinput>attrib -s -r c:\boot.ini</userinput></screen>

          <para>Edit to add the appropriate entries from the example
            <filename>boot.ini</filename> above, and restore the
            attributes:</para>

          <screen><prompt>C:\&gt;</prompt> <userinput>attrib +s +r c:\boot.ini</userinput></screen>

          <para>If FreeBSD is booting from the MBR, restore it with the DOS
            <command>fdisk</command> command after you reconfigure them to
            boot from their native partitions.</para>

          <para>For FreeBSD 3.x systems the procedure is somewhat
            simpler.</para>

          <para>If FreeBSD is installed on the same disk as the NT boot
            partition simply copy <filename>/boot/boot1</filename> to
            <filename>C:\BOOTSECT.BSD</filename> However, if FreeBSD is
            installed on a different disk <filename>/boot/boot1</filename>
            will not work, <filename>/boot/boot0</filename> is needed.

            <warning>
              <para>DO NOT SIMPLY COPY <filename>/boot/boot0</filename>
                INSTEAD OF <filename>/boot/boot1</filename>, YOU WILL
                OVERWRITE YOUR PARTITION TABLE AND RENDER YOUR COMPUTER
                UN-BOOTABLE!</para>
            </warning>

            <filename>/boot/boot0</filename> needs to be installed using
              sysinstall by selecting the FreeBSD boot manager on the
              screen which asks if you wish to use a boot manager. This is
              because <filename>/boot/boot0</filename> has the partition
              table area filled with NULL characters but sysinstall copies
              the partition table before copying
              <filename>/boot/boot0</filename> to the MBR.</para>

          <para>When the FreeBSD boot manager runs it records the last
            OS booted by setting the active flag on the partition table
            entry for that OS and then writes the whole 512-bytes of itself
            back to the MBR so if you just copy
            <filename>/boot/boot0</filename> to
            <filename>C:\BOOTSECT.BSD</filename> then it writes an empty
            partition table, with the active flag set on one entry, to the
            MBR.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="lilo-bootloader">
          <para>How do I boot FreeBSD and Linux from LILO?</para>
        </question>

        <answer>
          <para>If you have FreeBSD and Linux on the same disk, just follow
            LILO's installation instructions for booting a non-Linux
            operating system.  Very briefly, these are:</para>

          <para>Boot Linux, and add the following lines to
            <filename>/etc/lilo.conf</filename>:</para>

            <programlisting>other=/dev/hda2
        table=/dev/hda
        label=FreeBSD</programlisting>

          <para>(the above assumes that your FreeBSD slice is known to Linux
            as <devicename>/dev/hda2</devicename>; tailor to suit your setup).
            Then, run <command>lilo</command> as <username>root</username> and you should be
            done.</para>

          <para>If FreeBSD resides on another disk, you need to add
            <literal>loader=/boot/chain.b</literal> to the LILO entry.
            For example:</para>

          <programlisting>other=/dev/dab4
        table=/dev/dab
        loader=/boot/chain.b
        label=FreeBSD</programlisting>

          <para>In some cases you may need to specify the BIOS drive number
            to the FreeBSD boot loader to successfully boot off the second
            disk.  For example, if your FreeBSD SCSI disk is probed by BIOS
            as BIOS disk 1, at the FreeBSD boot loader prompt you need to
            specify:</para>

          <screen>Boot: <userinput>1:da(0,a)/kernel</userinput></screen>

          <para>On FreeBSD 2.2.5 and later, you can configure
            &man.boot.8;
            to automatically do this for you at boot time.</para>

          <para>The <ulink
            URL="http://sunsite.unc.edu/LDP/HOWTO/mini/Linux+FreeBSD.html">
            Linux+FreeBSD mini-HOWTO</ulink> is a good reference for
            FreeBSD and Linux interoperability issues.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="booteasy-loader">
          <para>How do I boot FreeBSD and Linux using BootEasy?</para>
        </question>

        <answer>
          <para>Install LILO at the start of your Linux boot partition
            instead of in the Master Boot Record.   You can then boot LILO
            from BootEasy.</para>

          <para>If you are running Windows-95 and Linux this is recommended
            anyway, to make it simpler to get Linux booting again if you
            should need to reinstall Windows95 (which is a Jealous
            Operating System, and will bear no other Operating Systems in
            the Master Boot Record).</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="changing-bootprompt">
          <para>How do I change the boot prompt from <literal>???</literal> to
            something more meaningful?</para>
        </question>

        <answer>
          <para>You can not do that with the standard boot manager without
            rewriting it. There are a number of other boot managers
            in the <filename>sysutils</filename> ports category that
            provide this functionality.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="removable-drives">
          <para>I have a new removable drive, how do I use it?</para>
        </question>

        <answer>

          <para>Whether it is a removable drive like a ZIP or an EZ drive
            (or even a floppy, if you want to use it that way), or a new
            hard disk, once it is installed and recognized by the system,
            and you have your cartridge/floppy/whatever slotted in, things
            are pretty much the same for all devices.</para>

          <para><anchor id="disklabel">(this section is based on <ulink
            URL="http://www.vmunix.com/mark/FreeBSD/ZIP-FAQ.html">
            Mark Mayo's ZIP FAQ</ulink>)</para>

          <para>If it is a ZIP drive or a floppy, you have already got a DOS
            filesystem on it, you can use a command like this:</para>

          <screen>&prompt.root; <userinput>mount -t msdos /dev/fd0c /floppy</userinput></screen>

          <para>if it is a floppy, or this:</para>

          <screen>&prompt.root; <userinput>mount -t msdos /dev/da2s4 /zip</userinput></screen>

          <para>for a ZIP disk with the factory configuration.</para>

          <para>For other disks, see how they are laid out using
            &man.fdisk.8; or
            &man.sysinstall.8;.</para>

          <para>The rest of the examples will be for a ZIP drive on da2,
            the third SCSI disk.</para>

          <para>Unless it is a floppy, or a removable you plan on sharing
            with other people, it is probably a better idea to stick a BSD
            file system on it. You will get long filename support, at least a
            2X improvement in performance, and a lot more stability. First,
            you need to redo the DOS-level partitions/filesystems. You can
            either use &man.fdisk.8; or
            <filename>/stand/sysinstall</filename>, or for a small drive
            that you do not want to bother with multiple operating system
            support on, just blow away the whole FAT partition table
            (slices) and just use the BSD partitioning:</para>

          <screen>&prompt.root; <userinput>dd if=/dev/zero of=/dev/rda2 count=2</userinput>
&prompt.root; <userinput>disklabel -Brw da2 auto</userinput></screen>

          <para>You can use disklabel or
            <filename>/stand/sysinstall</filename> to create multiple BSD
            partitions. You will certainly want to do this if you are adding
            swap space on a fixed disk, but it is probably irrelevant on a
            removable drive like a ZIP.</para>

          <para>Finally, create a new file system, this one is on our ZIP
            drive using the whole disk:</para>

          <screen>&prompt.root; <userinput>newfs /dev/rda2c</userinput></screen>

          <para>and mount it:</para>

          <screen>&prompt.root; <userinput>mount /dev/da2c /zip</userinput></screen>

          <para>and it is probably a good idea to add a line like this to
            <filename>/etc/fstab</filename> (see &man.fstab.5;) so you can just type
            <command>mount /zip</command> in the future:</para>

          <programlisting>/dev/da2c /zip ffs rw,noauto 0 0</programlisting>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="mount-cd-superblock">
          <para>Why do I get <errorname>Incorrect super block</errorname> when
            mounting a CDROM?</para>
        </question>

        <answer>
          <para>You have to tell &man.mount.8; the type of the device
            that you want to mount.  This is described in the <ulink
            URL="../handbook/creating-cds.html"> Handbook section on
            optical media</ulink>, specifically the section <ulink
            URL="../handbook/creating-cds.html#MOUNTING-CD">Using Data
            CDs</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="cdrom-not-configured">
          <para>Why do I get <errorname>Device not configured</errorname> when
            mounting a CDROM?</para>
        </question>

        <answer>
          <para>This generally means that there is no CDROM in the
            CDROM drive, or the drive is not visible on the
            bus. Please see the <ulink
            URL="../handbook/creating-cds.html#MOUNTING-CD">Using Data
            CDs</ulink> section of the Handbook for a detailed
            discussion of this issue.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="cdrom-unicode-filenames">
          <para>Why do all non-English characters in filenames show up as
            <quote>?</quote> on my CDs when mounted in FreeBSD?</para>
        </question>

        <answer>
          <para>Your CDROM probably uses the <quote>Joliet</quote>
            extension for storing information about files and
            directories.  This is discussed in the Handbook chapter on
            <ulink URL="../handbook/creating-cds.html">creating and
            using CDROMs</ulink>, specifically the section on <ulink
            URL="../handbook/creating-cds.html#MOUNTING-CD">Using Data
            CDROMs</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="burncd-isofs">
          <para>I burned a CD under FreeBSD and now I can not read it
            under any other operating system. Why?</para>
        </question>
  
        <answer>
          <para>You most likely burned a raw file to your CD, rather
            than creating an ISO 9660 filesystem.  Take a look at the
            <ulink URL="../handbook/creating-cds.html">Handbook
            chapter on creating CDROMs</ulink>, particularly the
            section on <ulink
            URL="../handbook/creating-cds.html#RAWDATA-CD">burning raw
            data CDs</ulink>.</para>
	</answer>
      </qandaentry>

      <qandaentry>
        <question id="copy-cd">
          <para>How can I create an image of a data CD?</para>
        </question>

        <answer>
          <para>This is discussed in the Handbook section on <ulink
            url="../handbook/creating-cds.html#IMAGING-CD">duplicating
            data CDs</ulink>. For more on working with CDROMs, see the
            <ulink url="../handbook/creating-cds.html">Creating CDs
            Section</ulink> in the Storage chapter in the
            Handbook.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="mount-audio-CD">
          <para>Why can I not <command>mount</command> an audio
          CD?</para>
         </question>

        <answer>
          <para>If you try to mount an audio CD, you will get an error
            like <errorname>cd9660: /dev/acd0c: Invalid
            argument</errorname>.  This is because
            <command>mount</command> only works on filesystems.  Audio
            CDs do not have filesystems; they just have data.  You
            need a program that reads audio CDs, such as the
            <filename role="package">audio/xmcd</filename> port.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="user-floppymount">
          <para>How do I let ordinary users mount floppies, CDROMs and
            other removable media?</para>
        </question>

        <answer>
          <para>Ordinary users can be permitted to mount devices. Here is
            how:</para>

          <procedure>
            <step>
              <para>As <username>root</username> set the sysctl variable
                <varname>vfs.usermount</varname> to
                <literal>1</literal>.</para>

              <screen>&prompt.root; <userinput>sysctl -w vfs.usermount=1</userinput></screen>
            </step>

            <step>
              <para>As <username>root</username> assign the appropriate
                permissions to the block device associated with the
                removable media.</para>

              <para>For example, to allow users to mount the first floppy
                drive, use:</para>

              <screen>&prompt.root; <userinput>chmod 666 /dev/fd0</userinput></screen>

              <para>To allow users in the group
                <groupname>operator</groupname> to mount the CDROM drive,
                use:</para>

              <screen>&prompt.root; <userinput>chgrp operator /dev/cd0c</userinput>
&prompt.root; <userinput>chmod 640 /dev/cd0c</userinput></screen>
            </step>

            <step>
              <para>Finally, add the line
                <literal><varname>vfs.usermount</varname>=1</literal> to the file
                <filename>/etc/sysctl.conf</filename> so that it is reset
                at system boot time.</para>
            </step>
          </procedure>

          <para>All users can now mount the floppy
            <devicename>/dev/fd0</devicename> onto a directory that they
            own:</para>

          <screen>&prompt.user; <userinput>mkdir ~/my-mount-point</userinput>
&prompt.user; <userinput>mount -t msdos /dev/fd0 ~/my-mount-point</userinput></screen>

          <para>Users in group <groupname>operator</groupname> can now
            mount the CDROM <devicename>/dev/cd0c</devicename> onto a
            directory that they own:</para>

          <screen>&prompt.user; <userinput>mkdir ~/my-mount-point</userinput>
&prompt.user; <userinput>mount -t msdos /dev/cd0c ~/my-mount-point</userinput></screen>

          <para>Unmounting the device is simple:</para>

          <screen>&prompt.user; <userinput>umount <filename>~/my-mount-point</></userinput></screen>

          <para>Enabling <varname>vfs.usermount</varname>, however, has
            negative security implications.  A better way to access MSDOS
            formatted media is to use the <ulink
            URL="http://www.FreeBSD.org/cgi/ports.cgi?query=%5Emtools-&amp;stype=name">mtools</ulink> package in the ports collection.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="du-vs-df">
          <para>The <command>du</command> and <command>df</command>
            commands show different amounts of disk space available.
            What is going on?</para>
        </question>

        <answer>
          <para>You need to understand what <command>du</command> and
            <command>df</command> really do.  <command>du</command>
            goes through the directory tree, measures how large each
            file is, and presents the totals.  <command>df</command>
            just asks the filesystem how much space it has left.  They
            seem to be the same thing, but a file without a directory
            entry will affect <command>df</command> but not
            <command>du</command>.</para>

          <para>When a program is using a file, and you delete the
            file, the file is not really removed from the filesystem
            until the program stops using it.  The file is immediately
            deleted from the directory listing, however.  You can see
            this easily enough with a program such as
            <command>more</command>.  Assume you have a file large
            enough that its presence affects the output of
            <command>du</command> and <command>df</command>.  (Since
            disks can be so large today, this might be a
            <emphasis>very</emphasis> large file!)  If you delete this
            file while using <command>more</command> on it,
            <command>more</command> does not immediately choke and
            complain that it cannot view the file.  The entry is
            simply removed from the directory so no other program or
            user can access it.  <command>du</command> shows that it
            is gone &mdash; it has walked the directory tree and the file
            is not listed.  <command>df</command> shows that it is
            still there, as the filesystem knows that
            <command>more</command> is still using that space.  Once
            you end the <command>more</command> session,
            <command>du</command> and <command>df</command> will
            agree.</para>

          <para>Note that softupdates can delay the freeing of disk
            space; you might need to wait up to 30 seconds for the
            change to be visible!</para>

          <para>This situation is common on web servers.  Many people
            set up a FreeBSD web server and forget to rotate the log
            files.  The access log fills up <filename>/var</filename>.
            The new administrator deletes the file, but the system
            still complains that the partition is full.  Stopping and
            restarting the web server program would free the file,
            allowing the system to release the disk space.  To prevent
            this from happening, set up &man.newsyslog.8;.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="add-swap-space">
          <para>How can I add more swap space?</para>
        </question>

        <answer>
          <para>In the <ulink
          url="../handbook/config-tuning.html">Configuration and
          Tuning</ulink> section of the Handbook, you will find a
          <ulink
          url="../handbook/adding-swap-space.html">section</ulink>
          describing how to do this.</para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="admin">
    <title>System Administration</title>

    <qandaset>
      <qandaentry>
        <question id="startup-config-files">
          <para>Where are the system start-up configuration files?</para>
        </question>

        <answer>

          <para>From 2.0.5R to 2.2.1R, the primary configuration file is
            <filename>/etc/sysconfig</filename>. All the options are to be
            specified in this file and other files such as
            <filename>/etc/rc</filename> (see &man.rc.8;)
            and <filename>/etc/netstart</filename> just include it.</para>

          <para>Look in the <filename>/etc/sysconfig</filename> file and
            change the value to match your system. This file is filled with
            comments to show what to put in there.</para>

          <para>In post-2.2.1 and 3.0, <filename>/etc/sysconfig</filename>
            was renamed to a more self-describing &man.rc.conf.5;
            file and the syntax cleaned up a bit in the process.
            <filename>/etc/netstart</filename> was also renamed to
            <filename>/etc/rc.network</filename> so that all files could be
            copied with a
            <command>cp
            /usr/src/etc/rc* /etc</command> command.</para>

          <para>And, in 3.1 and later, <filename>/etc/rc.conf</filename>
            has been moved to <filename>/etc/defaults/rc.conf</filename>.
            <emphasis>Do not edit this file!</emphasis> Instead, if there
            is any entry in <filename>/etc/defaults/rc.conf</filename> that
            you want to change, you should copy the line into
            <filename>/etc/rc.conf</filename> and change it there.</para>

          <para>For example, if you wish to start named, the DNS server
            included with FreeBSD in FreeBSD 3.1 or later, all you need to
            do is:</para>
          <screen>&prompt.root; <userinput>echo named_enable="YES" &gt;&gt; /etc/rc.conf</userinput></screen>

          <para>To start up local services in FreeBSD 3.1 or later, place
            shell scripts in the <filename>/usr/local/etc/rc.d</filename>
            directory. These shell scripts should be set executable, and
            end with a .sh. In FreeBSD 3.0 and earlier releases, you should
            edit the <filename>/etc/rc.local</filename> file.</para>

          <para>The <filename>/etc/rc.serial</filename> is for serial port
            initialization (e.g. locking the port characteristics, and so
            on.).</para>

          <para>The <filename>/etc/rc.i386</filename> is for Intel-specifics
            settings, such as iBCS2 emulation or the PC system console
            configuration.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="adding-users">
          <para>How do I add a user easily?</para>
        </question>

        <answer>
          <para>Use the &man.adduser.8;
            command. For more complicated usage, the &man.pw.8;
            command.</para>

          <para>To remove the user again, use the &man.rmuser.8;
            command. Once again, &man.pw.8; will work as
            well.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="root-not-found-cron-errors">
          <para>Why do I keep getting messages like <errorname>root: not
            found</errorname> after editing my crontab file?</para>
        </question>

        <answer>
          <para>This is normally caused by editing the system crontab
            (<filename>/etc/crontab</filename>) and then using
            &man.crontab.1; to install it:</para>

          <screen>&prompt.root; <userinput>crontab /etc/crontab</userinput></screen>

          <para>This is not the correct way to do things.  The system
            crontab has a different format to the per-user crontabs
            which &man.crontab.1; updates (the &man.crontab.5; manual
            page explains the differences in more detail).</para>

          <para>If this is what you did, the extra crontab is simply a
            copy of <filename>/etc/crontab</filename> in the wrong
            format it.  Delete it with the command:</para>

          <screen>&prompt.root; <userinput>crontab -r</userinput></screen>

          <para>Next time, when you edit
            <filename>/etc/crontab</filename>, you should not do
            anything to inform &man.cron.8; of the changes, since it
            will notice them automatically.</para>

          <para>If you want something to be run once per day, week, or
            month, it is probably better to add shell scripts
            <filename>/usr/local/etc/periodic</filename>, and let the
            &man.periodic.8; command run from the system cron schedule
            it with the other periodic system tasks.</para>

          <para>The actual reason for the error is that the system
            crontab has an extra field, specifying which user to run the
            command as.  In the default system crontab provided with
            FreeBSD, this is <username>root</username> for all entries.
            When this crontab is used as the <username>root</username>
            user's crontab (which is <emphasis>not</emphasis> the
            same as the system crontab), &man.cron.8; assumes the string
            <literal>root</literal> is the first word of the command to
            execute, but no such command exists.</para>
        </answer>
      </qandaentry>

      <qandaentry>
	<question id="su-wheel-group">
	  <para>Why do I get the error, <errorname>you are not in the correct
	    group to su root</errorname> when I try to su to root?</para>
	</question>

	<answer>
	  <para>This is a security feature.  In order to su to
	    <username>root</username> (or any other account with superuser
	    privileges), you must be in the <groupname>wheel</groupname>
	    group.  If this feature were not there, anybody with an account
	    on a system who also found out <username>root</username>'s
	    password would be able to gain superuser level access to the
	    system.  With this feature, this is not strictly true;
	    &man.su.1; will prevent them from even trying to enter the
	    password if they are not in <groupname>wheel</groupname>.</para>

	  <para>To allow someone to su to <username>root</username>, simply
	    put them in the <groupname>wheel</groupname> group.</para>
	</answer>
      </qandaentry>

      <qandaentry>
        <question id="rcconf-readonly">
          <para>I made a mistake in <filename>rc.conf</filename>,
            or another startup file, and
            now I cannot edit it because the filesystem is read-only.
            What should I do?</para>
        </question>

        <answer>
          <para>When you get the prompt to enter the shell
            pathname, simply press <literal>ENTER</literal>, and run
            <command>mount /</command> to re-mount the root filesystem in
            read/write mode. You may also need to run <command>mount -a -t
            ufs</command> to mount the filesystem where your favourite
            editor is defined. If your favourite editor is on a network
            filesystem, you will need to either configure the network
            manually before you can mount network filesystems, or use an
            editor which resides on a local filesystem, such as
            &man.ed.1;.</para>

          <para>If you intend to use a full screen editor such
            as &man.vi.1; or &man.emacs.1;, you may also need to
            run <command>export TERM=cons25</command> so that these
            editors can load the correct data from the &man.termcap.5;
            database.</para>

          <para>Once you have performed these steps, you can edit
            <filename>/etc/rc.conf</filename> as you usually would
            to fix the syntax error.  The error message displayed
            immediately after the kernel boot messages should tell you
            the number of the line in the file which is at fault.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="printer-setup">
          <para>Why am I having trouble setting up my printer?</para>
        </question>

        <answer>
          <para>Please have a look at the Handbook entry on printing. It
            should cover most of your problem. See the <ulink
            URL="../handbook/printing.html">
            Handbook entry on printing</ulink>.</para>

	  <para>Some printers require a host-based driver to do any kind of
	    printing.  These so-called <quote>WinPrinters</quote> are not
	    natively supported by FreeBSD.  If your printer does not work
	    in DOS or Windows NT 4.0, it is probably a WinPrinter.  Your
	    only hope of getting one of these to work is to check if the
	    <filename role="package">print/pnm2ppa</filename> port supports it.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="keyboard-mappings">
          <para>How can I correct the keyboard mappings for my system?</para>
        </question>

        <answer>
          <para>Please see the Handbook section on <ulink
            url="../handbook/using-localization.html">using
            localization</ulink>, specifically the section on <ulink
            url="../handbook/using-localization.html#SETTING-CONSOLE">console
            setup</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="pnp-resources">
          <para>Why do I get messages like: <errorname>unknown: &lt;PNP0303&gt;
            can't assign resources</errorname> on boot?</para>
        </question>

        <answer>
	  <para>The following is an excerpt from a post to the
	    freebsd-current mailing list.</para>

	  <blockquote>
	    <attribution>&a.wollman;, 24 April 2001</attribution>

	    <para>The <quote>can't assign resources</quote> messages
	      indicate that the devices are legacy ISA devices for which a
	      non-PnP-aware driver is compiled into the kernel.  These
	      include devices such as keyboard controllers, the
	      programmable interrupt controller chip, and several other
	      bits of standard infrastructure.  The resources cannot be
	      assigned because there is already a driver using those
	      addresses.</para>
	  </blockquote>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="user-quotas">
          <para>Why can I not get user quotas to work properly?</para>
        </question>

        <answer>

            <orderedlist>
              <listitem>
                <para>Do not turn on quotas on <filename>/</filename>,</para>
              </listitem>

              <listitem>
                <para>Put the quota file on the file system that the quotas
                  are to be enforced on. ie:</para>

                <informaltable frame="none">
                  <tgroup cols="2">
                    <thead>
                      <row>
                        <entry>Filesystem</entry>
                        <entry>Quota file</entry>
                      </row>
                    </thead>

                    <tbody>
                      <row>
                        <entry><filename>/usr</filename></entry>
                        <entry><filename>/usr/admin/quotas</filename></entry>
                      </row>

                      <row>
                        <entry><filename>/home</filename></entry>
                        <entry><filename>/home/admin/quotas</filename></entry>
                      </row>

                      <row>
                        <entry>&hellip;</entry>
                        <entry>&hellip;</entry>
                      </row>
                    </tbody>
                  </tgroup>
                </informaltable>
              </listitem>
            </orderedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="sysv-ipc">
          <para>Does FreeBSD support System V IPC primitives?</para>
        </question>

        <answer>
          <para>Yes, FreeBSD supports System V-style IPC.  This includes
            shared memory, messages and semaphores.  You need to add the
            following lines to your kernel config to enable them.</para>

          <programlisting>options    SYSVSHM          # enable shared memory
options    SYSVSEM          # enable for semaphores
options    SYSVMSG          # enable for messaging</programlisting>

            <note>
              <para>In FreeBSD 3.2 and later, these options are already
                part of the <emphasis>GENERIC</emphasis> kernel, which
                means they should already be compiled into your
                system.</para>
            </note>

          <para>Recompile and install your kernel.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="uucpmail">
          <para>How do I use sendmail for mail delivery with UUCP?</para>
        </question>

        <answer>

          <para>The sendmail configuration that ships with FreeBSD is
            suited for sites that connect directly to the Internet.
            Sites that wish to exchange their mail via UUCP must install
            another sendmail configuration file.</para>

          <para>Tweaking <filename>/etc/sendmail.cf</filename> manually is
            considered something for purists. Sendmail version 8 comes with
            a new approach of generating config files via some
            &man.m4.1;
            preprocessing, where the actual hand-crafted configuration is
            on a higher abstraction level. You should use the configuration
            files under
            <filename>/usr/src/usr.sbin/sendmail/cf</filename>.</para>

          <para>If you did not install your system with full sources,
            the sendmail config stuff has been broken out into a separate
            source distribution tarball just for you. Assuming you have got
            your CDROM mounted, do:</para>

          <screen>&prompt.root; <userinput>cd /cdrom/src</userinput>
&prompt.root; <userinput>cat scontrib.?? | tar xzf - -C /usr/src contrib/sendmail</userinput></screen>

          <para>Do not panic, this is only a few hundred kilobytes in size.
            The file <filename>README</filename> in the
            <filename>cf</filename> directory can serve as a basic
            introduction to m4 configuration.</para>

          <para>For UUCP delivery, you are best advised to use the
            <literal>mailertable</literal> feature.  This constitutes a
            database that sendmail can use to base its routing decision
            upon.</para>

          <para>First, you have to create your <filename>.mc</filename>
            file.  The directory
            <filename>/usr/src/usr.sbin/sendmail/cf/cf</filename> is the
            home of these files.  Look around, there are already a few
            examples.  Assuming you have named your file
            <filename>foo.mc</filename>, all you need to do in order to
            convert it into a valid <filename>sendmail.cf</filename>
            is:</para>

          <screen>&prompt.root; <userinput>cd /usr/src/usr.sbin/sendmail/cf/cf</userinput>
&prompt.root; <userinput>make foo.cf</userinput>
&prompt.root; <userinput>cp foo.cf /etc/mail/sendmail.cf</userinput></screen>

          <para>A typical <filename>.mc</filename> file might look
            like:</para>


          <programlisting>VERSIONID(`<replaceable>Your version number</replaceable>')
OSTYPE(bsd4.4)

FEATURE(accept_unresolvable_domains)
FEATURE(nocanonify)
FEATURE(mailertable, `hash -o /etc/mail/mailertable')

define(`UUCP_RELAY', <replaceable>your.uucp.relay</replaceable>)
define(`UUCP_MAX_SIZE', 200000)
define(`confDONT_PROBE_INTERFACES')

MAILER(local)
MAILER(smtp)
MAILER(uucp)

Cw    <replaceable>your.alias.host.name</replaceable>
Cw    <replaceable>youruucpnodename.UUCP</replaceable></programlisting>

          <para>The lines containing <literal>accept_unresolvable_domains</literal>,
            <literal>nocanonify</literal>, and <literal>confDONT_PROBE_INTERFACES</literal> features will prevent any usage
            of the DNS during mail delivery.  The
            <literal>UUCP_RELAY</literal> clause is needed for bizarre
            reasons, do not ask.  Simply put an Internet hostname there that
            is able to handle .UUCP pseudo-domain addresses; most likely,
            you will enter the mail relay of your ISP there.</para>

          <para>Once you have got this, you need this file called
            <filename>/etc/mail/mailertable</filename>.  If have only
            one link to the outside that is used for all your mails,
            the following file will be enough:</para>

          <programlisting>#
# makemap hash /etc/mail/mailertable.db &lt; /etc/mail/mailertable
.                             uucp-dom:<replaceable>your.uucp.relay</replaceable></programlisting>

          <para>A more complex example might look like this:</para>

          <programlisting>#
# makemap hash /etc/mail/mailertable.db &lt; /etc/mail/mailertable
#
horus.interface-business.de   uucp-dom:horus
.interface-business.de        uucp-dom:if-bus
interface-business.de         uucp-dom:if-bus
.heep.sax.de                  smtp8:%1
horus.UUCP                    uucp-dom:horus
if-bus.UUCP                   uucp-dom:if-bus
.                             uucp-dom:</programlisting>


          <para>As you can see, this is part of a real-life file.  The
            first three lines handle special cases where domain-addressed
            mail should not be sent out to the default route, but instead
            to some UUCP neighbor in order to <quote>shortcut</quote> the
            delivery path. The next line handles mail to the local Ethernet
            domain that can be delivered using SMTP. Finally, the UUCP
            neighbors are mentioned in the .UUCP pseudo-domain notation, to
            allow for a <literal><replaceable>uucp-neighbor
            </replaceable>!<replaceable>recipient</replaceable></literal>
            override of the default rules. The last line is always a single
            dot, matching everything else, with UUCP delivery to a UUCP
            neighbor that serves as your universal mail gateway to the
            world. All of the node names behind the
            <literal>uucp-dom:</literal> keyword must be valid UUCP
            neighbors, as you can verify using the command
            <literal>uuname</literal>.</para>

          <para>As a reminder that this file needs to be converted into a
            DBM database file before being usable, the command line to
            accomplish this is best placed as a comment at the top of
            the mailertable.  You always have to execute this command
            each time you change your mailertable.</para>

          <para>Final hint: if you are uncertain whether some particular
            mail routing would work, remember the <option>-bt</option>
            option to sendmail. It starts sendmail in <emphasis>address
            test mode</emphasis>; simply enter <literal>3,0</literal>,
            followed by the address you wish to test for the mail routing.
            The last line tells you the used internal mail agent, the
            destination host this agent will be called with, and the
            (possibly translated) address. Leave this mode by typing
            Control-D.</para>

          <screen>&prompt.user; <userinput>sendmail -bt</userinput>
ADDRESS TEST MODE (ruleset 3 NOT automatically invoked)
Enter &lt;ruleset&gt; &lt;address&gt;
<prompt>&gt;</prompt> <userinput>3,0 foo@example.com</userinput>
canonify           input: foo @ example . com
...
parse            returns: $# uucp-dom $@ <replaceable>your.uucp.relay</replaceable> $: foo &lt; @ example . com . &gt;
<prompt>&gt;</prompt> <userinput>^D</userinput></screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ispmail">
          <para>How do I set up mail with a dialup connection to the
            'net?</para>
        </question>

        <answer>
          <para>If you have got a statically assigned IP number, you
            should not need to adjust anything from the default.  Set
            your host name up as your assigned Internet name and
            sendmail will do the rest.</para>

          <para>If you have got a dynamically assigned IP number and
            use a dialup PPP connection to the Internet, you will
            probably be given a mailbox on your ISPs mail server. Lets
            assume your ISPs domain is <hostid
            role="domainname">myISP.com</hostid>, and that your user
            name is <username>user</username>. Lets also assume you
            have called your machine <hostid
            role="fqdn">bsd.home</hostid> and that your ISP has told
            you that you may use <hostid
            role="fqdn">relay.myISP.com</hostid> as a mail
            relay.</para>

          <para>In order to retrieve mail from your mailbox, you will
            need to install a retrieval
            agent. <application>Fetchmail</application> is a good
            choice as it supports many different protocols. Usually,
            POP3 will be provided by your ISP. If you have chosen to
            use user-PPP, you can automatically fetch your mail when a
            connection to the 'net is established with the following
            entry in <filename>/etc/ppp/ppp.linkup</filename>:</para>

          <programlisting>MYADDR:
  !bg su user -c fetchmail</programlisting>

          <para>If you are using <application>sendmail</application>
            (as shown below) to deliver mail to non-local accounts,
            put the command</para>

          <programlisting>  !bg su user -c "sendmail -q"</programlisting>

          <para>after the above shown entry. This forces
            <application>sendmail</application> to process your
            mailqueue as soon as the connection to the 'net is
            established.</para>

          <para>I am assuming that you have an account for
            <username>user</username> on <hostid
            role="fqdn">bsd.home</hostid>. In the home directory of
            <username>user</username> on <hostid
            role="fqdn">bsd.home</hostid>, create a
            <filename>.fetchmailrc</filename> file:</para>

          <programlisting>poll myISP.com protocol pop3 fetchall pass MySecret</programlisting>

          <para>This file should not be readable by anyone except
            <username>user</username> as it contains the password
            <literal>MySecret</literal>.</para>

          <para>In order to send mail with the correct
            <literal>from:</literal> header, you must tell
            <application>sendmail</application> to use
            <literal>user@myISP.com</literal> rather than
            <literal>user@bsd.home</literal>. You may also wish to
            tell <application>sendmail</application> to send all mail
            via <hostid role="fqdn">relay.myISP.com</hostid>, allowing
            quicker mail transmission.</para>

          <para>The following <filename>.mc</filename> file should
            suffice:</para>

          <programlisting>VERSIONID(`bsd.home.mc version 1.0')
OSTYPE(bsd4.4)dnl
FEATURE(nouucp)dnl
MAILER(local)dnl
MAILER(smtp)dnl
Cwlocalhost
Cwbsd.home
MASQUERADE_AS(`myISP.com')dnl
FEATURE(allmasquerade)dnl
FEATURE(masquerade_envelope)dnl
FEATURE(nocanonify)dnl
FEATURE(nodns)dnl
define(`SMART_HOST', `relay.myISP.com')
Dmbsd.home
define(`confDOMAIN_NAME',`bsd.home')dnl
define(`confDELIVERY_MODE',`deferred')dnl</programlisting>

          <para>Refer to the previous section for details of how to
            turn this <filename>.mc</filename> file into a
            <filename>sendmail.cf</filename> file.  Also, do not
            forget to restart <application>sendmail</application>
            after updating <filename>sendmail.cf</filename>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="sendmail-alternative">
          <para>What other mail-server software can I use, instead of
            Sendmail?</para>
        </question>

        <answer>
          <para><ulink url="http://www.sendmail.org/">Sendmail</ulink> is
            the default mail-server software for FreeBSD, but you can
            easily replace it with one of the other MTA (for instance,
            an MTA installed from the ports).</para>

          <para>There are various alternative MTA's in the ports tree
            already, with <filename role="package">mail/exim</filename>,
            <filename role="package">mail/postfix</filename>, <filename role="package">mail/qmail</filename>,
            <filename role="package">mail/zmailer</filename>, being some of the most popular
            choises.</para>

          <para>Diversity is nice, and the fact that you have many
            different mail-servers to chose from is considered a
            good thing; therefore try to avoid
            asking questions like <quote>Is Sendmail better than
            Qmail?</quote> in the mailing lists.  If you do feel like
            asking, first check the mailing list archives.  The
            advantages and disadvantages of each and every one of the
            available MTA's have already been discussed a few
            times.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="forgot-root-pw">
          <para>I have forgotten the root password!  What do I do?</para>
        </question><answer>

          <para>Do not Panic!  Simply restart the system, type
            <userinput>boot -s</userinput> at the Boot: prompt (just
            <userinput>-s</userinput> for FreeBSD releases before 3.2) to
            enter Single User mode. At the question about the shell to use,
            hit ENTER. You will be dropped to a &prompt.root; prompt. Enter
            <command>mount -u /</command> to remount your root filesystem
            read/write, then run <command>mount -a</command> to remount all
            the filesystems. Run <command>passwd root</command> to change
            the root password then run &man.exit.1; to continue
            booting.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="CAD-reboot">
          <para>How do I keep Control-Alt-Delete from rebooting the
            system?</para>
        </question>

        <answer>

          <para>If you are using syscons (the default console driver)
            in FreeBSD 2.2.7-RELEASE or later,
            build and install a new kernel with the line</para>

          <programlisting>options SC_DISABLE_REBOOT</programlisting>

          <para>in the configuration file. If you use the PCVT console
            driver in FreeBSD 2.2.5-RELEASE or later, use the following
            kernel configuration line instead:</para>

          <programlisting>options PCVT_CTRL_ALT_DEL</programlisting>

          <para>For older versions of FreeBSD, edit the keymap you are
            using for the console and replace the <literal>boot</literal>
            keywords with <literal>nop</literal>. The default keymap is
            <filename>/usr/share/syscons/keymaps/us.iso.kbd</filename>. You
            may have to instruct <filename>/etc/rc.conf</filename> to load
            this keymap explicitly for the change to take effect. Of course
            if you are using an alternate keymap for your country, you
            should edit that one instead.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="dos-to-unix-txt">
          <para>How do I reformat DOS text files to Unix ones?</para>
        </question>

        <answer>

          <para>Simply use this perl command:</para>

          <screen>&prompt.user; <userinput>perl -i.bak -npe 's/\r\n/\n/g' file ...</userinput></screen>

          <para>file is the file(s) to process.  The modification is done
            in-place, with the original file stored with a .bak
            extension.</para>

          <para>Alternatively you can use the
            &man.tr.1;
            command:</para>

          <screen>&prompt.user; <userinput>tr -d '\r' &lt; <replaceable>dos-text-file</replaceable> &gt; <replaceable>unix-file</replaceable></userinput></screen>

          <para><replaceable>dos-text-file</replaceable> is the file
            containing DOS text while <replaceable>unix-file</replaceable>
            will contain the converted output.  This can be quite a bit
            faster than using perl.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="kill-by-name">
          <para>How do I kill processes by name?</para>
        </question><answer>

          <para>Use &man.killall.1;.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="root-acl">
          <para>Why is su bugging me about not being in
            <username>root</username>'s ACL?</para>
        </question>

        <answer>

          <para>The error comes from the Kerberos distributed
            authentication system.  The problem is not fatal but annoying.
            You can either run su with the -K option, or uninstall
            Kerberos as described in the next question.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="uninstall-kerberos">
          <para>How do I uninstall Kerberos?</para>
        </question>

        <answer>

          <para>To remove Kerberos from the system, reinstall the bin
            distribution for the release you are running.  If you have
            the CDROM, you can mount the cd (we will assume on /cdrom)
            and run</para>

          <screen>&prompt.root; <userinput>cd /cdrom/bin</userinput>
&prompt.root; <userinput>./install.sh</userinput></screen>

          <para>Alternately, you can remove all "MAKE_KERBEROS"
            options from <filename>/etc/make.conf</filename> and rebuild
            world.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="add-pty">
          <para>How do I add pseudoterminals to the system?</para>
        </question>

        <answer>

          <para>If you have lots of telnet, ssh, X, or screen users,
            you will probably run out of pseudoterminals.  Here is how to
            add more:</para>

            <procedure>
              <step>
                <para>Build and install a new kernel with the line</para>

                <programlisting>pseudo-device pty 256</programlisting>

                <para>in the configuration file.</para>
              </step>

              <step>
                <para>Run the commands</para>

                <screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>sh MAKEDEV pty{1,2,3,4,5,6,7}</userinput></screen>

                <para>to make 256 device nodes for the new terminals.</para>

              </step>

              <step>
                <para>Edit <filename>/etc/ttys</filename> and add lines
                for each of the 256 terminals. They should match the form
                of the existing entries, i.e. they look like</para>

                <programlisting>ttyqc none network</programlisting>

                <para>The order of the letter designations is
                  <literal>tty[pqrsPQRS][0-9a-v]</literal>, using a
                  regular expression.  </para>
              </step>

              <step>
                <para>Reboot the system with the new kernel and you are
                  ready to go.</para>
              </step>
            </procedure>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="create-snd0">
          <para>Why can I not create the snd0 device?</para>
        </question>

        <answer>
          <para>There is no <devicename>snd</devicename> device.  The name
            is used as a shorthand for the various devices that make up the
            FreeBSD sound driver, such as <devicename>mixer</devicename>,
            <devicename>sequencer</devicename>, and
            <devicename>dsp</devicename>.</para>

          <para>To create these devices you should</para>

          <screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>sh MAKEDEV snd0</userinput></screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="reread-rc">
          <para>How do I re-read <filename>/etc/rc.conf</filename> and re-start <filename>/etc/rc</filename> without
            a reboot?</para>
        </question>

        <answer>

          <para>Go into single user mode and then back to multi user
            mode.</para>

          <para>On the console do:</para>

          <screen>&prompt.root; <userinput>shutdown now</userinput>
(Note: without -r or -h)

&prompt.root; <userinput>return</userinput>
&prompt.root; <userinput>exit</userinput></screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="sandbox">
          <para>What is a sandbox?</para>
        </question><answer>

          <para><quote>Sandbox</quote> is a security term.  It can mean
            two things:</para>

            <itemizedlist>
              <listitem>

                <para>A process which is placed inside a set of virtual
                  walls that are designed to prevent someone who breaks
                  into the process from being able to break into the wider
                  system.</para>

                <para>The process is said to be able to
                  <quote>play</quote> inside the walls.  That is,
                  nothing the process does in regards to executing code is
                  supposed to be able to breech the walls so you do not
                  have to do a detailed audit of its code to be able to
                  say certain things about its security.</para>

                <para>The walls might be a userid, for example.  This is
                  the definition used in the security and named man
                  pages.</para>

                <para>Take the <literal>ntalk</literal> service, for
                  example (see /etc/inetd.conf). This service used to run
                  as userid root. Now it runs as userid tty. The tty user
                  is a sandbox designed to make it more difficult for
                  someone who has successfully hacked into the system via
                  ntalk from being able to hack beyond that user id.</para>
              </listitem>

              <listitem>

                <para>A process which is placed inside a simulation of the
                  machine. This is more hard-core. Basically it means that
                  someone who is able to break into the process may believe
                  that he can break into the wider machine but is, in fact,
                  only breaking into a simulation of that machine and not
                  modifying any real data.</para>

                <para>The most common way to accomplish this is to build a
                  simulated environment in a subdirectory and then run the
                  processes in that directory chroot'd (i.e.
                  <filename>/</filename> for that process is this
                  directory, not the real <filename>/</filename> of the
                  system).</para>

                <para>Another common use is to mount an underlying
                  filesystem read-only and then create a filesystem layer
                  on top of it that gives a process a seemingly writeable
                  view into that filesystem. The process may believe it is
                  able to write to those files, but only the process sees
                  the effects - other processes in the system do not,
                  necessarily.</para>

                <para>An attempt is made to make this sort of sandbox so
                  transparent that the user (or hacker) does not realize
                  that he is sitting in it.</para>
              </listitem>
            </itemizedlist>

          <para>Unix implements two core sandboxes.  One is at the
            process level, and one is at the userid level.</para>

          <para>Every Unix process is completely firewalled off from every
            other Unix process.  One process cannot modify the address
            space of another.  This is unlike Windows where a process
            can easily overwrite the address space of any other, leading
            to a crash.</para>

          <para>A Unix process is owned by a particular userid.  If the
            userid is not the <username>root</username> user, it serves to firewall the process
            off from processes owned by other users.  The userid is also
            used to firewall off on-disk data.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="securelevel">
          <para>What is securelevel?</para>
        </question>

        <answer>
          <para>The securelevel is a security mechanism implemented in the
            kernel.  Basically, when the securelevel is positive, the
            kernel restricts certain tasks; not even the superuser (i.e.,
            <username>root</username>) is allowed to do them.  At the time
            of this writing, the securelevel mechanism is capable of, among
            other things, limiting the ability to,</para>

          <itemizedlist>
            <listitem>
              <para>unset certain file flags, such as
                <literal>schg</literal> (the system immutable flag),</para>
            </listitem>

            <listitem>
              <para>write to kernel memory via
                <devicename>/dev/mem</devicename> and
                <devicename>/dev/kmem</devicename>,</para>
            </listitem>

            <listitem>
              <para>load kernel modules, and</para>
            </listitem>

            <listitem>
              <para>alter &man.ipfirewall.4; rules.</para>
            </listitem>
          </itemizedlist>

          <para>To check the status of the securelevel on a running system,
            simply execute the following command:</para>

          <screen>&prompt.root; <userinput>sysctl kern.securelevel</userinput></screen>

          <para>The output will contain the name of the &man.sysctl.8;
            variable (in this case, <varname>kern.securelevel</varname>)
            and a number.  The latter is the current value of the
            securelevel.  If it is positive (i.e., greater than 0), at
            least some of the securelevel's protections are enabled.</para>

          <para>You cannot lower the securelevel of a running system; being
            able to do that would defeat its purpose.  If you need to do a
            task that requires that the securelevel be non-positive (e.g.,
            an <maketarget>installworld</maketarget> or changing the date),
            you will have to change the securelevel setting in
            <filename>/etc/rc.conf</filename> (you want to look for the
            <varname>kern_securelevel</varname> and
            <varname>kern_securelevel_enable</varname> variables) and
            reboot.</para>

          <para>For more information on securelevel and the specific things
            all the levels do, please consult the &man.init.8; manual
            page.</para>

            <warning>
              <para>Securelevel is not a silver bullet; it has many known
                deficiencies.  More often than not, it provides a false
                sense of security.</para>

              <para>One of its biggest problems is that in order for it to
                be at all effective, all files used in the boot process up
                until the securelevel is set must be protected.  If an
                attacker can get the system to execute their code prior to
                the securelevel being set (which happens quite late in the
                boot process since some things the system must do at
                start-up cannot be done at an elevated securelevel), its
                protections are invalidated.  While this task of protecting
                all files used in the boot process is not technically
                impossible, if it is achieved, system maintenance will
                become a nightmare since one would have to take the system
                down, at least to single-user mode, to modify a
                configuration file.</para>

              <para>This point and others are often discussed on the
                mailing lists, particularly freebsd-security.  Please search
                the archives <ulink
                url="../../../../search/index.html">here</ulink> for an
                extensive discussion.  Some people are hopeful that
                securelevel will soon go away in favor of a more
                fine-grained mechanism, but things are still hazy in this
                respect.</para>

              <para>Consider yourself warned.</para>
            </warning>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="release-candidate">
          <para>I tried to update my system to the latest -STABLE, but
            got -RC or -BETA!  What is going on?</para>
        </question>

        <answer>
          <para>Short answer: it is just a name.  RC stands for
            <quote>Release Candidate</quote>.  It signifies that a
            release is imminent.  In FreeBSD, -BETA is typically synonymous
            with the code freeze before a release.</para>

          <para>Long answer: FreeBSD derives its releases from one of
            two places.  Major, dot-zero, releases, such as
            3.0-RELEASE and 4.0-RELEASE, are branched from the head of
            the development stream, commonly referred to as <link
            linkend="current">-CURRENT</link>.  Minor releases, such
            as 3.1-RELEASE or 4.2-RELEASE, have been snapshots of the active
            <link linkend="stable">-STABLE</link> branch.  Starting with
	    4.3-RELEASE, each release also now has its own branch which can be
	    tracked by people requiring an extremely conservative rate
	    of development (typically only security advisories).</para>

          <para>When a release is about to be made, the branch from
            which it will be derived from has to undergo a certain
            process.  Part of this process is a code freeze.  When a
            code freeze is initiated, the name of the branch is
            changed to reflect that it is about to become a release.
            For example, if the branch used to be called 4.0-STABLE,
            its name will be changed to 4.1-BETA to signify the code
            freeze and signify that extra pre-release testing should
            be happening.  Bug fixes can still be committed to be part
            of the release.  When the source code is in shape for the
            release the name will be changed to 4.1-RC to signify that a
            release is about to be made from it.  Once in the RC stage,
            only the most critical bugs found can be fixed.
            Once the release, 4.1-RELEASE in this example, has been made,
            the branch will be renamed to 4.1-STABLE.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="kernel-chflag-failure">
          <para>I tried to install a new kernel, and the chflags failed.
                How do I get around this?</para>
        </question>

        <answer>
          <para>Short answer: You are probably at security level
            greater than 0.  Reboot directly to single user mode to
            install the kernel.</para>

          <para>Long answer: FreeBSD disallows changing system flags
            at security levels greater than 0.  You can check your
            security level with the command:</para>

          <screen>&prompt.root; <userinput>sysctl kern.securelevel</userinput></screen>

           <para>You cannot lower the security level; you have to boot to
             single mode to install the kernel, or change the security
             level in <filename>/etc/rc.conf</filename> then reboot. See
             the &man.init.8; man page for details on securelevel, and see
             <filename>/etc/defaults/rc.conf</filename> and the
             &man.rc.conf.5; man page for more information on
             rc.conf.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="kernel-securelevel-time">
          <para>I cannot change the time on my system by more than one second!
                How do I get around this?</para>
        </question>

        <answer>
          <para>Short answer: You are probably at security level
            greater than 1.  Reboot directly to single user mode to
            change the date.</para>

          <para>Long answer: FreeBSD disallows changing the time by
              more that one second at security levels greater than 1.  You
              can check your security level with the command:</para>

          <screen>&prompt.root; <userinput>sysctl kern.securelevel</userinput></screen>

           <para>You cannot lower the security level; you have to boot
             to single mode to change the date, or change the security
             level in <filename>/etc/rc.conf</filename> then reboot. See
             the &man.init.8; man page for details on securelevel, and
             see <filename>/etc/defaults/rc.conf</filename> and the
             &man.rc.conf.5; man page for more information on rc.conf.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="statd-mem-leak">
          <para>Why is <command>rpc.statd</command> using 256 megabytes of
            memory?</para>
        </question>

        <answer>
          <para>No, there is no memory leak, and it is not using 256 Mbytes
            of memory.  It simply likes to (i.e., always does) map an
            obscene amount of memory into its address space for convenience.
            There is nothing terribly wrong with this from a technical
            standpoint; it just throws off things like &man.top.1; and
            &man.ps.1;.</para>

          <para>&man.rpc.statd.8; maps its status file (resident on
            <filename>/var</filename>) into its address space; to save
            worrying about remapping it later when it needs to grow, it maps
            it with a generous size.  This is very evident from the source
            code, where one can see that the length argument to &man.mmap.2;
            is <literal>0x10000000</literal>, or one sixteenth of the
            address space on an IA32, or exactly 256MB.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="unsetting-schg">
          <para>Why can I not unset the <literal>schg</literal> file
            flag?</para>
        </question>

        <answer>
          <para>You are running at an elevated (i.e., greater than 0)
            securelevel.  Lower the securelevel and try again.  For more
            information, see <link linkend="securelevel">the FAQ entry on
            securelevel</link> and the &man.init.8; manual page.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ssh-shosts">
	  <para>Why does SSH authentication through
	    <filename>.shosts</filename> not work by default in recent
	    versions of FreeBSD?</para>
	</question>

	<answer>
	  <para>The reason why <filename>.shosts</filename>
	    authentication does not work by default in more recent
	    versions of FreeBSD is because &man.ssh.1; 
	    is not installed suid root by default.  To
	    <quote>fix</quote> this, you can do one of the
	    following:</para>

	  <itemizedlist>
	    <listitem>
	      <para>As a permanent fix, set
		<makevar>ENABLE_SUID_SSH</makevar> to <literal>true</literal>
		in <filename>/etc/make.conf</filename> and rebuild ssh
		(or run <command>make world</command>).</para>
	    </listitem>

	    <listitem>
	      <para>As a temporary fix, change the mode on
		<filename>/usr/bin/ssh</filename> to <literal>4555</literal>
		by running <command>chmod 4755 /usr/bin/ssh</command> as
		<username>root</username>.  Then add
		<makevar>ENABLE_SUID_SSH= true</makevar> to
		<filename>/etc/make.conf</filename> so the change takes
		effect the next time <command>make world</command> is
		run.</para>
	    </listitem>
	  </itemizedlist>
	</answer>
      </qandaentry>

      <qandaentry>
        <question id="vnlru">
          <para>What is <literal>vnlru</literal>?</para>
        </question>

        <answer>
          <para><literal>vnlru</literal> flushes and frees vnodes when
            the system hits the <varname>kern.maxvnodes</varname>
            limit.  This kernel thread sits mostly idle, and only
            activates if you have a huge amount of RAM and are
            accessing tens of thousands of tiny files.</para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="x">
    <title>The X Window System and Virtual Consoles</title>

    <qandaset>
      <qandaentry>
        <question id="running-X">
          <para>I want to run X, how do I go about it?</para>
        </question>

        <answer>

          <para>The easiest way is to simply specify that you want to
            run X during the installation process.</para>

          <para>Then read and follow the documentation on the
            <command>xf86config</command> tool, which assists you in configuring
            XFree86(tm) for your particular graphics card/mouse/etc.</para>

          <para>You may also wish to investigate the Xaccel server.
            See the section on <link linkend="xig">Xi Graphics</link> or
            <link linkend="metrox">Metro Link</link> for more details.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="running-X-securelevels">
          <para>I <emphasis>tried</emphasis> to run X, but I get an
            <errorname>KDENABIO failed (Operation not permitted)</errorname>
            error when I type <command>startx</command>. What do I do
            now?</para>
        </question>

        <answer>
          <para>Your system is running at a raised securelevel, is not
            it?  It is, indeed, impossible to start X at a raised
            securelevel.  To see why, look at the &man.init.8; man
            page.</para>

          <para>So the question is what else you should do instead,
            and you basically have two choices: set your securelevel
            back down to zero (usually from <filename>/etc/rc.conf</filename>),
            or run &man.xdm.1; at boot time (before the securelevel is
            raised).</para>

          <para>See <xref linkend="xdm-boot"> for more information about
            running &man.xdm.1; at boot time.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="x-and-moused">
          <para>Why does my mouse not work with X?</para>
        </question>

        <answer>
          <para>If you are using syscons (the default console driver),
            you can configure FreeBSD to support a mouse pointer on each
            virtual screen. In order to avoid conflicting with X, syscons
            supports a virtual device called
            <devicename>/dev/sysmouse</devicename>. All mouse events received
            from the real mouse device are written to the sysmouse device
            via moused. If you wish to use your mouse on one or more
            virtual consoles, <emphasis>and</emphasis> use X, see
            <xref linkend="moused" remap="another section"> and set up
            moused.</para>

          <para>Then edit <filename>/etc/XF86Config</filename> and make
            sure you have the following lines.</para>

          <programlisting>Section         Pointer
Protocol        "SysMouse"
Device          "/dev/sysmouse"
.....</programlisting>

          <para>The above example is for XFree86 3.3.2 or later.  For
            earlier versions, the <emphasis>Protocol</emphasis> should be
            <emphasis>MouseSystems</emphasis>.</para>

          <para>Some people prefer to use <devicename>/dev/mouse</devicename>
            under X.  To make this work, <devicename>/dev/mouse</devicename>
            should be linked to
            <devicename>/dev/sysmouse</devicename> (see &man.sysmouse.4;):</para>

          <screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>rm -f mouse</userinput>
&prompt.root; <userinput>ln -s sysmouse mouse</userinput></screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="x-and-wheel">
          <para>My mouse has a fancy wheel.  Can I use it in X?</para>
        </question>

        <answer>
          <para>Yes.  But you need to customize X client programs. See <ulink
            URL="http://www.inria.fr/koala/colas/mouse-wheel-scroll/">
            Colas Nahaboo's web page
            (http://www.inria.fr/koala/colas/mouse-wheel-scroll/)
            </ulink>.</para>

          <para>If you want to use the <application>imwheel</application>
            program, just follow these simple steps.</para>

          <orderedlist>
            <listitem>
              <para>Translate the Wheel Events</para>

              <para>The <application>imwheel</application> program
                works by translating mouse button 4 and mouse button 5
                events into key events.  Thus, you have to get the
                mouse driver to translate mouse wheel events to button
                4 and 5 events.  There are two ways of doing this, the
                first way is to have &man.moused.8; do the
                translation.  The second way is for the X server
                itself to do the event translation.</para>

              <orderedlist>
                <listitem>
                  <para>Using &man.moused.8; to Translate Wheel
                    Events</para>

                  <para>To have &man.moused.8; perform the event
                    translations, simply add <option>-z 4</option> to
                    the command line used to start &man.moused.8;.
                    For example, if you normally start &man.moused.8;
                    via <command>moused -p /dev/psm0</command> you
                    would start it by entering <command>moused -p
                    /dev/psm0 -z 4</command> instead.  If you start
                    &man.moused.8; automatically during bootup via
                    <filename>/etc/rc.conf</filename>, you can simply
                    add <option>-z 4</option> to the
                    <varname>moused_flags</varname> variable in
                    <filename>/etc/rc.conf</filename>.</para>

                  <para>You now need to tell X that you have a 5
                    button mouse.  To do this, simply add the line
                    <literal>Buttons 5</literal> to the
                    <quote>Pointer</quote> section of
                    <filename>/etc/XF86Config</filename>.  For
                    example, you might have the following
                    <quote>Pointer</quote> section in
                    <filename>/etc/XF86Config</filename>.</para>

                  <example>
                    <title><quote>Pointer</quote> Section for Wheeled
                      Mouse in XFree86 3.3.x series XF86Config with moused
                      Translation</title>

                    <programlisting>Section "Pointer"
   Protocol        "SysMouse"
   Device          "/dev/sysmouse"
   Buttons         5
EndSection</programlisting>
                  </example>

                  <example>
                    <title><quote>InputDevice</quote> Section for Wheeled
                      Mouse in XFree86 4.x series XF86Config with X Server
                      Translation</title>

                    <programlisting>Section "InputDevice"
   Identifier      "Mouse1"
   Driver          "mouse"
   Option          "Protocol" "auto"
   Option          "Device" "/dev/sysmouse"
   Option          "Buttons" "5"
EndSection</programlisting>
                  </example>

                  <example>
                    <title><quote>.emacs</quote> example for naive
                      page scrolling with Wheeled Mouse</title>
                    <programlisting>;; wheel mouse
(global-set-key [mouse-4] 'scroll-down)
(global-set-key [mouse-5] 'scroll-up)</programlisting>
                  </example>

                </listitem>

                <listitem>
                  <para>Using Your X Server to Translate the Wheel
                    Events</para>

                  <para>If you are not running &man.moused.8;, or if
                    you do not want &man.moused.8; to translate your
                    wheel events, you can have the X server do the
                    event translation instead.  This requires a couple
                    of modifications to your
                    <filename>/etc/XF86Config</filename> file.  First,
                    you need to choose the proper protocol for your
                    mouse.  Most wheeled mice use the
                    <quote>IntelliMouse</quote> protocol.  However,
                    XFree86 does support other protocols, such as
                    <quote>MouseManPlusPS/2</quote> for the Logitech
                    MouseMan+ mice.  Once you have chosen the protocol
                    you will use, you need to add a
                    <varname>Protocol</varname> line to the
                    <quote>Pointer</quote> section.</para>

                  <para>Secondly, you need to tell the X server to
                    remap wheel scroll events to mouse buttons 4 and
                    5.  This is done with the
                    <varname>ZAxisMapping</varname> option.</para>

                  <para>For example, if you are not using
                      &man.moused.8;, and you have an IntelliMouse
                      attached to the PS/2 mouse port you would use
                      the following in
                      <filename>/etc/XF86Config</filename>.</para>

                  <example>
                    <title><quote>Pointer</quote> Section for Wheeled
                      Mouse in <filename>XF86Config</filename> with X
                      Server Translation</title>

                    <programlisting>Section "Pointer"
   Protocol        "IntelliMouse"
   Device          "/dev/psm0"
   ZAxisMapping    4 5
EndSection</programlisting>
                  </example>

                  <example>
                    <title><quote>InputDevice</quote> Section for Wheeled
                      Mouse in XFree86 4.x series XF86Config with X Server
                      Translation</title>

                    <programlisting>Section "InputDevice"
   Identifier      "Mouse1"
   Driver          "mouse"
   Option          "Protocol" "auto"
   Option          "Device" "/dev/psm0"
   Option          "ZAxisMapping" "4 5"
EndSection</programlisting>
                  </example>

                  <example>
                    <title><quote>.emacs</quote> example for naive
                      page scrolling with Wheeled Mouse</title>
                    <programlisting>;; wheel mouse
(global-set-key [mouse-4] 'scroll-down)
(global-set-key [mouse-5] 'scroll-up)</programlisting>
                  </example>

                </listitem>
              </orderedlist>
            </listitem>

            <listitem>
              <para>Install <application>imwheel</application></para>

              <para>Next, install <application>imwheel</application>
                from the Ports collection.  It can be found in the
                <filename>x11</filename> category.  This program will
                map the wheel events from your mouse into keyboard
                events.  For example, it might send <keycap>Page
                Up</keycap> to a program when you scroll the wheel
                forwards.  <application>Imwheel</application> uses a
                configuration file to map the wheel events to
                key presses so that it can send different keys to
                different applications.  The default
                <application>imwheel</application> configuration file
                is installed in
                <filename>/usr/X11R6/etc/imwheelrc</filename>.  You
                can copy it to <filename>~/.imwheelrc</filename> and
                then edit it if you wish to customize
                <application>imwheel</application>'s configuration.
                The format of the configuration file is documented in
                &man.imwheel.1;.</para>
            </listitem>

            <listitem>
              <para>Configure <application>Emacs</application> to Work
                with <application>Imwheel</application>
                (<emphasis>optional</emphasis>)</para>

              <para>If you use <application>emacs</application> or
                <application>Xemacs</application>, then you need to
                add a small section to your
                <filename>~/.emacs</filename> file.  For
                <application>emacs</application>, add the
                following:</para>

              <example>
                <title><application>Emacs</application> Configuration
                  for <application>Imwheel</application></title>

                <programlisting>;;; For imwheel
(setq imwheel-scroll-interval 3)
(defun imwheel-scroll-down-some-lines ()
  (interactive)
  (scroll-down imwheel-scroll-interval))
(defun imwheel-scroll-up-some-lines ()
  (interactive)
  (scroll-up imwheel-scroll-interval))
(global-set-key [?\M-\C-\)] 'imwheel-scroll-up-some-lines)
(global-set-key [?\M-\C-\(] 'imwheel-scroll-down-some-lines)
;;; end imwheel section</programlisting>
              </example>

              <para>For <application>Xemacs</application>, add the
                following to your <filename>~/.emacs</filename> file
                instead:</para>

              <example>
                <title><application>Xemacs</application> Configuration
                  for <application>Imwheel</application></title>

                <programlisting>;;; For imwheel
(setq imwheel-scroll-interval 3)
(defun imwheel-scroll-down-some-lines ()
  (interactive)
  (scroll-down imwheel-scroll-interval))
(defun imwheel-scroll-up-some-lines ()
  (interactive)
  (scroll-up imwheel-scroll-interval))
(define-key global-map [(control meta \))] 'imwheel-scroll-up-some-lines)
(define-key global-map [(control meta \()] 'imwheel-scroll-down-some-lines)
;;; end imwheel section</programlisting>
              </example>
            </listitem>

            <listitem>
              <para>Run <application>Imwheel</application></para>

              <para>You can just type <command>imwheel</command>
                in an xterm to start it up once it is installed.  It
                will background itself and take effect immediately.
                If you want to always use
                <application>imwheel</application>, simply add it to
                your <filename>.xinitrc</filename> or
                <filename>.xsession</filename> file.  You can safely
                ignore any warnings <application>imwheel</application>
                displays about PID files.  Those warnings only apply
                to the Linux version of
                <application>imwheel</application>.</para>
            </listitem>
          </orderedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="window-menu-weird">
          <para>Why do X Window menus and dialog boxes not work right?</para>
        </question>

        <answer>
          <para>Try turning off the Num Lock key.</para>

          <para>If your Num Lock key is on by default at boot-time, you
            may add the following line in the <literal>Keyboard</literal>
            section of the <filename>XF86Config</filename> file.</para>

          <programlisting># Let the server do the NumLock processing.  This should only be
# required when using pre-R6 clients
    ServerNumLock</programlisting>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="virtual-console">
          <para>What is a virtual console and how do I make more?</para>
        </question>

        <answer>
          <para>Virtual consoles, put simply, enable you to have several
            simultaneous sessions on the same machine without doing anything
            complicated like setting up a network or running X.</para>

          <para>When the system starts, it will display a login prompt on
            the monitor after displaying all the boot messages. You can
            then type in your login name and password and start working (or
            playing!) on the first virtual console.</para>

          <para>At some point, you will probably wish to start another
            session, perhaps to look at documentation for a program
            you are running or to read your mail while waiting for an
            FTP transfer to finish. Just do Alt-F2 (hold down the Alt
            key and press the F2 key), and you will find a login prompt
            waiting for you on the second <quote>virtual console</quote>!
            When you want to go back to the original session, do
            Alt-F1.</para>

          <para>The default FreeBSD installation has three virtual consoles
            enabled (8 starting with 3.3-RELEASE), and Alt-F1, Alt-F2, and
            Alt-F3 will switch between these virtual consoles.</para>

          <para>To enable more of them, edit
            <filename>/etc/ttys</filename> (see &man.ttys.5;)
            and add entries for <devicename>ttyv4</devicename>
            to <devicename>ttyvc</devicename> after the comment on
            <quote>Virtual terminals</quote>:</para>

          <programlisting># Edit the existing entry for ttyv3 in /etc/ttys and change
# "off" to "on".
ttyv3   "/usr/libexec/getty Pc"         cons25  on secure
ttyv4   "/usr/libexec/getty Pc"         cons25  on secure
ttyv5   "/usr/libexec/getty Pc"         cons25  on secure
ttyv6   "/usr/libexec/getty Pc"         cons25  on secure
ttyv7   "/usr/libexec/getty Pc"         cons25  on secure
ttyv8   "/usr/libexec/getty Pc"         cons25  on secure
ttyv9   "/usr/libexec/getty Pc"         cons25  on secure
ttyva   "/usr/libexec/getty Pc"         cons25  on secure
ttyvb   "/usr/libexec/getty Pc"         cons25  on secure</programlisting>

          <para>Use as many or as few as you want.  The more virtual
            terminals you have, the more resources that are used; this
            can be important if you have 8MB RAM or less.  You may also
            want to change the <literal>secure</literal>
            to <literal>insecure</literal>.</para>

            <important>
              <para>If you want to run an X server you
                <emphasis>must</emphasis> leave at least one virtual
                terminal unused (or turned off) for it to use. That is to
                say that if you want to have a login prompt pop up for all
                twelve of your Alt-function keys, you are out of luck - you
                can only do this for eleven of them if you also want to run
                an X server on the same machine.</para>
            </important>

          <para>The easiest way to disable a console is by turning it off.
            For example, if you had the full 12 terminal allocation
            mentioned above and you wanted to run X, you would change
            settings for virtual terminal 12 from:</para>

          <programlisting>ttyvb   "/usr/libexec/getty Pc"         cons25  on  secure</programlisting>

          <para>to:</para>

          <programlisting>ttyvb   "/usr/libexec/getty Pc"         cons25  off secure</programlisting>

          <para>If your keyboard has only ten function keys, you would
            end up with:</para>

<programlisting>ttyv9   "/usr/libexec/getty Pc"         cons25  off secure
ttyva   "/usr/libexec/getty Pc"         cons25  off secure
ttyvb   "/usr/libexec/getty Pc"         cons25  off secure</programlisting>

          <para>(You could also just delete these lines.)</para>

          <para>Once you have edited
            <filename>/etc/ttys</filename>, the next step is to make sure that you
            have enough virtual terminal devices.  The easiest way to do
            this is:</para>

          <screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>sh MAKEDEV vty12</userinput></screen>

          <para>Next, the easiest (and cleanest) way to activate the
            virtual consoles is to reboot.  However, if you really do not
            want to reboot, you can just shut down the X Window system
            and execute (as <username>root</username>):</para>

          <screen>&prompt.root; <userinput>kill -HUP 1</userinput></screen>

          <para>It is imperative that you completely shut down X Window if
            it is running, before running this command.  If you do not,
            your system will probably appear to hang/lock up after
            executing the kill command.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="vty-from-x">
          <para>How do I access the virtual consoles from X?</para>
        </question>

        <answer>
          <para>Use <keycombo action="simul">
              <keycap>Ctrl</keycap>
              <keycap>Alt</keycap>
              <keycap>F<replaceable>n</replaceable></keycap>
            </keycombo> to switch back to a virtual console.
            <keycombo action="simul">
              <keycap>Ctrl</keycap>
              <keycap>Alt</keycap>
              <keycap>F1</keycap>
            </keycombo> would return you to the first virtual console.</para>

          <para>Once you are back to a text console, you can then use
            <keycombo action="simul">
              <keycap>Alt</keycap>
              <keycap>F<replaceable>n</replaceable></keycap>
            </keycombo> as normal to move between them.</para>

          <para>To return to the X session, you must switch to the virtual
            console running X.  If you invoked X from the command line, (e.g.,
            using <command>startx</command>) then the X session will attach to
            the next unused virtual console, not the text console from which
            it was invoked.  If you have eight active virtual terminals then X
            will be running on the ninth, and you would use
            <keycombo action="simul">
              <keycap>Alt</keycap>
              <keycap>F9</keycap>
            </keycombo> to return.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="xdm-boot">
          <para>How do I start XDM on boot?</para>
        </question><answer>

          <para>There are two schools of thought on how to start <ulink
            URL="http://www.FreeBSD.org/cgi/man.cgi?manpath=xfree86&amp;query=xdm">
            xdm</ulink>. One school starts xdm from
            <filename>/etc/ttys</filename> (see &man.ttys.5;)
            using the supplied example, while the other simply runs xdm
            from
            <filename>rc.local</filename> (see &man.rc.8;)
            or from a <filename>X.sh</filename> script in
            <filename>/usr/local/etc/rc.d</filename>. Both are equally
            valid, and one may work in situations where the other does not.
            In both cases the result is the same: X will popup a graphical
            login: prompt.</para>

          <para>The ttys method has the advantage of documenting which
            vty X will start on and passing the responsibility of
            restarting the X server on logout to init.  The rc.local
            method makes it easy to kill xdm if there is a problem
            starting the X server.</para>

          <para>If loaded from rc.local, <command>xdm</command> should
            be started without any arguments (i.e., as a daemon). xdm must
            start AFTER getty runs, or else getty and xdm will conflict,
            locking out the console. The best way around this is to have
            the script sleep 10 seconds or so then launch xdm.</para>

          <para>If you are to start <command>xdm</command> from
            <filename>/etc/ttys</filename>, there still is a chance of
            conflict between <command>xdm</command> and
            &man.getty.8;. One way to avoid this is to add the
            <literal>vt</literal> number in the
            <filename>/usr/X11R6/lib/X11/xdm/Xservers</filename>
            file.</para>

          <programlisting>:0 local /usr/X11R6/bin/X vt4</programlisting>

          <para>The above example will direct the X server to run in
            <devicename>/dev/ttyv3</devicename>. Note the number is offset by
            one. The X server counts the vty from one, whereas the FreeBSD
            kernel numbers the vty from zero.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="xconsole-failure">
          <para>Why do I get <errorname>Couldn't open console</errorname>
            when I run xconsole?</para>
        </question>

        <answer>
          <para>If you start <application>X</application>
            with
            <command>startx</command>, the permissions on
            <devicename>/dev/console</devicename> will
            <emphasis>not</emphasis> get changed, resulting in
            things like
            <command>xterm -C</command> and
            <command>xconsole</command> not working.</para>

          <para>This is because of the way console permissions are set
            by default. On a multi-user system, one does not necessarily
            want just any user to be able to write on the system console.
            For users who are logging directly onto a machine with a VTY,
            the &man.fbtab.5;
            file exists to solve such problems.</para>

          <para>In a nutshell, make sure an uncommented line of the
            form</para>

          <programlisting>/dev/ttyv0 0600 /dev/console</programlisting>

          <para>is in
            <filename>/etc/fbtab</filename> (see &man.fbtab.5;) and it will ensure that whomever logs in on
            <devicename>/dev/ttyv0</devicename> will own the console.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="xfree86-root">
          <para>Before, I was able to run XFree86 as a regular user.  Why does
            it now say that I must be <username>root</username>?</para>
        </question>

        <answer>
          <para>All X servers need to be run as <username>root</username> in order to get direct
            access to your video hardware.  Older versions of XFree86
            (&lt;= 3.3.6) installed all bundled servers to be automatically
            run as <username>root</username> (setuid to <username>root</username>).  This is obviously a security
            hazard because X servers are large, complicated programs.
            Newer versions of XFree86 do not install the servers setuid to
            <username>root</username> for just this reason.</para>

          <para>Obviously, running an X server as the root user is not
            acceptable, nor a good idea security-wise.  There are two ways
            to be able to use X as a regular user.  The first is to use
            <command>xdm</command> or another display manager
            (e.g., <command>kdm</command>); the second is to use the
            <command>Xwrapper</command>.</para>

          <para><command>xdm</command> is a daemon that handles graphical
            logins.  It is usually started at boot time, and is responsible
            for authenticating users and starting their sessions; it is
            essentially the graphical counterpart of
            &man.getty.8; and &man.login.1;.  For
            more information on <command>xdm</command> see
            <ulink url="http://www.xfree86.org/support.html">the XFree86
            documentation</ulink>, and the <link linkend="xdm-boot">the FAQ
            entry</link> on it.</para>

          <para><command>Xwrapper</command> is the X server wrapper; it is
            a small utility to enable one to manually run an X server while
            maintaining reasonable safety.  It performs some sanity checks
            on the command line arguments given, and if they pass, runs the
            appropriate X server.  If you do not want to run a display
            manger for whatever reason, this is for you.  If you have
            installed the complete ports collection, you can find the port in
            <filename>/usr/ports/x11/wrapper</filename>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ps2-x">
          <para>Why does my PS/2 mouse misbehave under X?</para>
        </question>

        <answer>
          <para>Your mouse and the mouse driver may have somewhat become
            out of synchronization.</para>

          <para>In versions 2.2.5 and earlier, switching away from X to a
            virtual terminal and getting back to X again may make them
            re-synchronized.  If the problem occurs often, you may add the
            following option in your kernel configuration file and
            recompile it.</para>

          <programlisting>options PSM_CHECKSYNC</programlisting>

          <para>See the section on <link linkend="make-kernel">building
            a kernel</link> if you have no experience with building
            kernels.</para>

          <para>With this option, there should be less chance of
            synchronization problem between the mouse and the driver.
            If, however, you still see the problem, click any mouse
            button while holding the mouse still to re-synchronize the
            mouse and the driver.</para>

          <para>Note that unfortunately this option may not work with all
            the systems and voids the <quote>tap</quote> feature of the
            ALPS GlidePoint device attached to the PS/2 mouse port.</para>

          <para>In versions 2.2.6 and later, synchronization check is done
            in a slightly better way and is standard in the PS/2 mouse
            driver. It should even work with GlidePoint. (As the check code
            has become a standard feature, PSM_CHECKSYNC option is not
            available in these versions.) However, in rare case the driver
            may erroneously report synchronization problem and you may see
            the kernel message:</para>

          <programlisting>psmintr: out of sync (xxxx != yyyy)</programlisting>

          <para>and find your mouse does not seem to work properly.</para>

          <para>If this happens, disable the synchronization check code
            by setting the driver flags for the PS/2 mouse driver to 0x100.
            Enter <emphasis>UserConfig</emphasis> by giving the
            <option>-c</option> option at the boot prompt:</para>

          <screen>boot: <userinput>-c</userinput></screen>

          <para>Then, in the <emphasis>UserConfig</emphasis> command
            line, type:</para>

          <screen>UserConfig&gt; <userinput>flags psm0 0x100</userinput>
UserConfig&gt; <userinput>quit</userinput></screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ps2-mousesystems">
          <para>Why does my PS/2 mouse from MouseSystems not
            work?</para>
        </question>

        <answer>
          <para>There have been some reports that certain model of PS/2
            mouse from MouseSystems works only if it is put into the
            <quote>high resolution</quote> mode.  Otherwise, the mouse
            cursor may jump to the upper-left corner of the screen every
            so often.</para>

          <para>Unfortunately there is no workaround for versions 2.0.X
            and 2.1.X. In versions 2.2 through 2.2.5, apply the following
            patch to <filename>/sys/i386/isa/psm.c</filename> and rebuild
            the kernel. See the section on <link
            linkend="make-kernel">building a kernel</link> if you have no
            experience with building kernels.</para>

          <programlisting>@@ -766,6 +766,8 @@
     if (verbose &gt;= 2)
         log(LOG_DEBUG, "psm%d: SET_DEFAULTS return code:%04x\n",
             unit, i);
+    set_mouse_resolution(sc-&gt;kbdc, PSMD_RES_HIGH);
+
 #if 0
     set_mouse_scaling(sc-&gt;kbdc);        /* 1:1 scaling */
     set_mouse_mode(sc-&gt;kbdc);                /* stream mode */</programlisting>

          <para>In versions 2.2.6 or later, specify the flags 0x04 to
            the PS/2 mouse driver to put the mouse into the high
            resolution mode.  Enter <emphasis>UserConfig</emphasis> by
            giving the <option>-c</option> option at the boot prompt:</para>

          <screen>boot: <userinput>-c</userinput></screen>

          <para>Then, in the <emphasis>UserConfig</emphasis> command line,
            type:</para>

          <screen>UserConfig&gt; <userinput>flags psm0 0x04</userinput>
UserConfig&gt; <userinput>quit</userinput></screen>

          <para>See the previous section for another possible cause of mouse
            problems.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="imake-tmpl">
          <para>When building an X app, <command>imake</command> cannot
            find <filename>Imake.tmpl</filename>.  Where is it?</para>
        </question>

        <answer>

          <para><filename>Imake.tmpl</filename> is part of the Imake package, a standard X
            application building tool.  <filename>Imake.tmpl</filename>, as well as several
            header files that are required to build X apps, is contained
            in the X prog distribution. You can install this from sysinstall
            or manually from the X distribution files.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="mouse-button-reverse">
          <para>How do I reverse the mouse buttons?</para>
        </question>

        <answer>
          <para>Run the command
            <command>xmodmap -e "pointer = 3 2 1"</command> from your
            <filename>.xinitrc</filename> or <filename>.xsession</filename>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="install-splash">
          <para>How do I install a splash screen and where do I find
            them?</para>
        </question>

        <answer>

          <para>Just prior to the release of FreeBSD 3.1, a new feature
            was added to allow the display of <quote>splash</quote> screens
            during the boot messages. The splash screens currently must be
            a 256 color bitmap (<filename>*.BMP</filename>) or ZSoft PCX
            (<filename>*.PCX</filename>) file. In addition, they must have
            a resolution of 320x200 or less to work on standard VGA
            adapters. If you compile VESA support into your kernel, then
            you can use larger bitmaps up to 1024x768. Note that VESA
            support requires the <literal>VM86</literal> kernel option to
            be compiled into the kernel. The actual VESA support can either
            be compiled directly into the kernel with the
            <literal>VESA</literal> kernel config option or by loading the
            VESA kld module during bootup.</para>

          <para>To use a splash screen, you need to modify the startup
            files that control the boot process for FreeBSD. The files for
            this changed prior to the release of FreeBSD 3.2, so there are
            now two ways of loading a splash screen:</para>

            <itemizedlist>
              <listitem>
                <para>FreeBSD 3.1</para>

                <para>The first step is to find a bitmap version of your
                  splash screen. Release 3.1 only supports Windows bitmap
                  splash screens. Once you have found your splash screen of
                  choice copy it to <filename>/boot/splash.bmp</filename>.
                  Next, you need to have a
                  <filename>/boot/loader.rc</filename> file that contains
                  the following lines:</para>

                <programlisting>load kernel
load -t splash_image_data /boot/splash.bmp
load splash_bmp
autoboot</programlisting>

              </listitem>

              <listitem>
                <para>FreeBSD 3.2+</para>

                <para>In addition to adding support for PCX splash screens,
                  FreeBSD 3.2 includes a nicer way of configuring the boot
                  process. If you wish, you can use the method listed above
                  for FreeBSD 3.1. If you do and you want to use PCX,
                  replace <literal>splash_bmp</literal> with
                  <literal>splash_pcx</literal>. If, on the other hand, you
                  want to use the newer boot configuration, you need to
                  create a <filename>/boot/loader.rc</filename> file that
                  contains the following lines:</para>

                <programlisting>include /boot/loader.4th
start</programlisting>

                <para>and a <filename>/boot/loader.conf</filename> that
                  contains the following:</para>

                <programlisting>splash_bmp_load="YES"
bitmap_load="YES"</programlisting>

                <para>This assumes you are using
                  <filename>/boot/splash.bmp</filename> for your splash
                  screen.  If you would rather use a PCX file, copy it to
                  <filename>/boot/splash.pcx</filename>, create a
                  <filename>/boot/loader.rc</filename> as instructed
                  above, and create a
                  <filename>/boot/loader.conf</filename> that
                  contains:</para>

                <programlisting>splash_pcx_load="YES"
bitmap_load="YES"
bitmap_name="/boot/splash.pcx"</programlisting>

              </listitem>
            </itemizedlist>

          <para>Now all you need is a splash screen.  For that you can
            surf on over to the gallery at <ulink
            URL="http://www.baldwin.cx/splash/">http://www.baldwin.cx/splash/</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="windows-keys">
          <para>Can I use the Windows(tm) keys on my keyboard in X?</para>
        </question>

        <answer>
          <para>Yes. All you need to do is use &man.xmodmap.1; to define
            what function you wish them to perform.</para>

          <para>Assuming all <quote>Windows(tm)</quote> keyboards are
            standard then the keycodes for the 3 keys are</para>

          <itemizedlist>
            <listitem>
              <para>115 - Windows(tm) key, between the left-hand Ctrl and
                Alt keys</para>
            </listitem>

            <listitem>
              <para>116 - Windows(tm) key, to the right of the Alt-Gr
                key</para>
            </listitem>

            <listitem>
              <para>117 - Menu key, to the left of the right-hand Ctrl
                key</para>
            </listitem>
          </itemizedlist>

          <para>To have the left Windows(tm) key print a comma, try
            this.</para>

          <screen>&prompt.root; <userinput>xmodmap -e "keycode 115 = comma"</userinput></screen>

          <para>You will probably have to re-start your window manager
            to see the result.</para>

          <para>To have the Windows(tm) key-mappings enabled automatically
            every time you start X either put the <command>xmodmap</command>
            commands in your <filename>~/.xinitrc</filename> file or,
            preferably, create a file <filename>~/.xmodmaprc</filename> and
            include the <command>xmodmap</command> options, one per line,
            then add the line</para>

          <programlisting>xmodmap $HOME/.xmodmaprc</programlisting>

          <para>to your <filename>~/.xinitrc</filename>.</para>

	  <para>For example, you could map the 3 keys top be F13, F14, and
	    F15, respectively.  This would make it easy to map them to
	    useful functions within applications or your window
	    manager, as demonstrated further down.</para>

          <para>To do this put the following in
            <filename>~/.xmodmaprc</filename>.</para>

          <programlisting>keycode 115 = F13
keycode 116 = F14
keycode 117 = F15</programlisting>

	  <para>If you use <command>fvwm2</command>, for example, you
	    could map the keys
            so that F13 iconifies (or de-iconifies) the window the cursor
            is in, F14 brings the window the cursor is in to the front or,
            if it is already at the front, pushes it to the back, and F15
            pops up the main Workplace (application) menu even if the
            cursor is not on the desktop, which is useful if you do not have
            any part of the desktop visible (and the logo on the key
            matches its functionality).</para>

	  <para>The following entries in
	    <filename>~/.fvwmrc</filename> implement the
	    aforementioned setup:</para>

          <programlisting>Key F13        FTIWS    A        Iconify
Key F14        FTIWS    A        RaiseLower
Key F15        A        A        Menu Workplace Nop</programlisting>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="x-3d-acceleration">
          <para>How can I get 3D hardware acceleration for
            OpenGL?</para>
        </question>

        <answer>
          <para>The availability of 3D acceleration depends on the
            version of XFree86 you are using and the type of video chip
            you have.  If you have an NVIDIA chip, check out the
            <ulink url="http://nvidia.netexplorer.org/">FreeBSD NVIDIA
            Driver Initiative </ulink> page, which discusses 3D
            acceleration for NVIDIA chips using XFree86-4.  For other
            cards with XFree86-4, including the Matrox G200/G400, ATI
            Rage 128/Radeon, and 3dfx Voodoo 3, 4, 5, and Banshee,
            information on hardware acceleration is available on the
            <ulink
            url="http://gladstone.uoregon.edu/~eanholt/dri/">XFree86-4
            Direct Rendering on FreeBSD</ulink> page.  Users of
            XFree86 version 3.3 can use the Utah-GLX port found in
            <filename role="package">graphics/utah-glx</filename> to get limited accelerated
            OpenGL on the Matrox Gx00, ATI Rage Pro, SiS 6326, i810,
            Savage, and older NVIDIA chips.</para>
          </answer>
        </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="networking">
    <title>Networking</title>

    <qandaset>
      <qandaentry>
        <question id="diskless-booting">
          <para>Where can I get information on
            <quote>diskless booting</quote>?</para>
          </question>

          <answer>
            <para><quote>Diskless booting</quote> means that the FreeBSD
              box is booted over a network, and reads the necessary files
              from a server instead of its hard disk. For full details,
              please read <ulink URL="../handbook/diskless.html">the
              Handbook entry on diskless booting</ulink></para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="router">
          <para>Can a FreeBSD box be used as a dedicated network
            router?</para>
        </question>

        <answer>
          <para>Yes.  Please see the Handbook entry on <ulink
            url="../handbook/routing.html"> advanced
            networking</ulink>, specifically the section on <ulink
            url="../handbook/routing.html#DEDICATED-ROUTER">routing
            and gateways</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="win95-connection">
          <para>Can I connect my Win95 box to the Internet via
            FreeBSD?</para>
        </question>

        <answer>
          <para>Typically, people who ask this question have two PC's
            at home, one with FreeBSD and one with Win95; the idea is to
            use the FreeBSD box to connect to the Internet and then be able
            to access the Internet from the Windows95 box through the
            FreeBSD box. This is really just a special case of the previous
            question.</para> <para>... and the answer is yes! In FreeBSD
            3.x, user-mode &man.ppp.8; contains a <option>-nat</option> option. If
            you run &man.ppp.8; with the <option>-nat</option>,
            set <literal>gateway_enable</literal> to
            <emphasis>YES</emphasis> in <filename>/etc/rc.conf</filename>,
            and configure your Windows machine correctly, this should work
            fine.</para>

          <para>More detailed information about setting this up can be
            found in the <ulink
            URL="../ppp-primer/index.html">
            Pedantic PPP Primer</ulink> by Steve Sims.</para>

          <para>If you are using kernel-mode PPP, or have an Ethernet
            connection to the Internet, you will have to use
            &man.natd.8;. Please look at the
            <link linkend="natd">natd</link> section of this FAQ.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="slip-ppp-support">
          <para>Does FreeBSD support SLIP and PPP?</para>
        </question>

        <answer>
          <para>Yes.  See the manual pages for &man.slattach.8;,
            &man.sliplogin.8;, &man.ppp.8;, and &man.pppd.8;.  &man.ppp.8;
            and &man.pppd.8; provide support for both incoming and outgoing
            connections, while &man.sliplogin.8; deals exclusively with
            incoming connections, and &man.slattach.8; deals exclusively
            with outgoing connections.</para>

          <para>For more information on how to use these, please see the
            <ulink url="../handbook/ppp-and-slip.html">Handbook chapter on
            PPP and SLIP</ulink>.</para>

          <para>If you only have access to the Internet through a
            <quote>shell account</quote>, you may want to have a look
            at the <filename role="package">net/slirp</filename> package.  It can provide you
            with (limited) access to services such as ftp and http
            direct from your local machine.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="natd">
          <para>Does FreeBSD support NAT or Masquerading?</para>
        </question>

        <answer>
          <para>If you have a local subnet (one or more local machines),
            but have been allocated only a single IP number from your
            Internet provider (or even if you receive a dynamic IP number),
            you may want to look at the &man.natd.8;
            program. &man.natd.8; allows you to connect an
            entire subnet to the Internet using only a single IP
            number.</para>

          <para>The &man.ppp.8;
            program has similar functionality built in via
            the <option>-nat</option> switch.  The
            alias library (&man.libalias.3;) is used in both cases.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="parallel-connect">
          <para>How do I connect two FreeBSD systems over a parallel line
            using PLIP?</para>
        </question>

        <answer>
          <para>Please see the <ulink url="../handbook/plip.html">PLIP
          section</ulink> of the Handbook.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="create-dev-net">
          <para>Why can I not create a <devicename>/dev/ed0</devicename>
            device?</para>
        </question>

        <answer>
          <para>Because they aren't necessary. In the Berkeley
            networking framework, network interfaces are only directly
            accessible by kernel code. Please see the
            <filename>/etc/rc.network</filename> file and the manual
            pages for the various network programs mentioned there for
            more information. If this leaves you totally confused,
            then you should pick up a book describing network
            administration on another BSD-related operating system;
            with few significant exceptions, administering networking
            on FreeBSD is basically the same as on SunOS 4.0 or
            Ultrix.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ethernet-aliases">
          <para>How can I set up Ethernet aliases?</para>
        </question>

	<answer>
	  <para>If the alias is on the same subnet as an address
	    already configured on the interface, then add 
	    <literal>netmask 0xffffffff</literal> to your
	    &man.ifconfig.8; command-line, as in the following:</para>
	  <screen>&prompt.root; <userinput>ifconfig ed0 alias 192.0.2.2 netmask 0xffffffff</userinput></screen>
	  <para>Otherwise, just specify the network address and
	    netmask as usual:</para>
	  <screen>&prompt.root; <userinput>ifconfig ed0 alias 172.16.141.5 netmask 0xffffff00</userinput</screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="port-3c503">
          <para>How do I get my 3C503 to use the other network
            port?</para>
        </question>

        <answer>
          <para>If you want to use the other ports, you will have to specify
            an additional parameter on the
            &man.ifconfig.8; command line. The default port is
            <literal>link0</literal>. To use the AUI port instead of the
            BNC one, use <literal>link2</literal>.  These flags should be
            specified using the ifconfig_* variables in
            <filename>/etc/rc.conf</filename> (see &man.rc.conf.5;).</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="nfs">
          <para>Why am I having trouble with NFS and FreeBSD?</para>
        </question>

        <answer>
          <para>Certain PC network cards are better than others (to put
            it mildly) and can sometimes cause problems with network
            intensive applications like NFS.</para>

          <para>See <ulink URL="../handbook/nfs.html">
            the Handbook entry on NFS</ulink> for more information on
            this topic.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="nfs-linux">
          <para>Why can I not NFS-mount from a Linux box?</para>
        </question>

        <answer>
          <para>Some versions of the Linux NFS code only accept mount
            requests from a privileged port; try</para>

          <screen>&prompt.root; <userinput>mount -o -P linuxbox:/blah /mnt</userinput></screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="nfs-sun">
          <para>Why can I not NFS-mount from a Sun box?</para>
        </question>

        <answer>
          <para>Sun workstations running SunOS 4.X only accept mount
            requests from a privileged port; try</para>

          <screen>&prompt.root; <userinput>mount -o -P sunbox:/blah /mnt</userinput></screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="exports-errors">
          <para>Why does <command>mountd</command> keep telling me it
            <errorname>can't change attributes</errorname> and that I have a
            <errorname>bad exports list</errorname> on my FreeBSD NFS
            server?</para>
        </question>

        <answer>
          <para>The most frequent problem is not understanding the
            correct format of <filename>/etc/exports</filename>.
            Please review &man.exports.5; and the <ulink
            url="../handbook/nfs.html">NFS</ulink> entry in the
            Handbook, especially the section on <ulink
            url="../handbook/nfs.html#CONFIGURING-NFS">configuring
            NFS</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-nextstep">
          <para>Why am I having problems talking PPP to NeXTStep
            machines?</para>
        </question>

        <answer>

          <para>Try disabling the TCP extensions in
            <filename>/etc/rc.conf</filename> (see &man.rc.conf.5;) by changing the following variable to
            NO:</para>

          <programlisting>tcp_extensions=NO</programlisting>

          <para>Xylogic's Annex boxes are also broken in this regard and
            you must use the above change to connect thru them.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ip-multicast">
          <para>How do I enable IP multicast support?</para>
        </question>

        <answer>
          <para>Multicast host operations are fully supported in FreeBSD
            2.0 and later by default. If you want your box to run as a
            multicast router, you will need to recompile your kernel with
            the <literal>MROUTING</literal> option and run
            &man.mrouted.8;. FreeBSD 2.2 and later will start
            &man.mrouted.8; at boot time if the flag
            <literal>mrouted_enable</literal> is set to
            <literal>"YES"</literal> in
            <filename>/etc/rc.conf</filename>.</para>

          <para>MBONE tools are available in their own ports category,
            <ulink url="http://www.FreeBSD.org/ports/mbone.html">mbone</ulink>.  If you are looking for the conference tools
            <command>vic</command> and <command>vat</command>,
            look there!</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="dec-pci-chipset">
          <para>Which network cards are based on the DEC PCI
             chipset?</para>
        </question><answer>

          <para>Here is a list compiled by Glen Foster
             <email>gfoster@driver.nsta.org</email>,
             with some more modern additions:</para>

          <table>
            <title>Network cards based on the DEC PCI chipset</title>

            <tgroup cols=2>
              <thead>
                <row>
                  <entry>Vendor</entry>
                  <entry>Model</entry>
                </row>
              </thead>

              <tbody>
                <row>
                  <entry>ASUS</entry>
                  <entry>PCI-L101-TB</entry>
                </row>
                <row>
                  <entry>Accton</entry>
                  <entry>ENI1203</entry>
                </row>
                <row>
                  <entry>Cogent</entry>
                  <entry>EM960PCI</entry>
                </row>
                <row>
                  <entry>Compex</entry>
                  <entry>ENET32-PCI</entry>
                </row>
                <row>
                  <entry>D-Link</entry>
                  <entry>DE-530</entry>
                </row>
                <row>
                  <entry>Dayna</entry>
                  <entry>DP1203, DP2100</entry>
                </row>
                <row>
                  <entry>DEC</entry>
                  <entry>DE435, DE450</entry>
                </row>
                <row>
                  <entry>Danpex</entry>
                  <entry>EN-9400P3</entry>
                </row>
                <row>
                  <entry>JCIS</entry>
                  <entry>Condor JC1260</entry>
                </row>
                <row>
                  <entry>Linksys</entry>
                  <entry>EtherPCI</entry>
                </row>
                <row>
                  <entry>Mylex</entry>
                  <entry>LNP101</entry>
                </row>
                <row>
                  <entry>SMC</entry>
                  <entry>EtherPower 10/100 (Model 9332)</entry>
                </row>
                <row>
                  <entry>SMC</entry>
                  <entry>EtherPower (Model 8432)</entry>
                </row>
                <row>
                  <entry>TopWare</entry>
                  <entry>TE-3500P</entry>
                </row>
                <row>
                  <entry>Znyx (2.2.x)</entry>
                  <entry>ZX312, ZX314, ZX342, ZX345, ZX346, ZX348</entry>
                </row>
                <row>
                  <entry>Znyx (3.x)</entry>
                  <entry>ZX345Q, ZX346Q, ZX348Q, ZX412Q, ZX414, ZX442, ZX444,
                    ZX474, ZX478, ZX212, ZX214 (10mbps/hd)</entry>
                </row>
              </tbody>
            </tgroup>
          </table>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="fqdn-hosts">
          <para>Why do I have to use the FQDN for hosts on my
            site?</para>
        </question>

        <answer>
          <para>You will probably find that the host is actually in a
            different domain; for example, if you are in foo.example.org and
            you wish to reach a host called <hostid>mumble</hostid> in the
            <hostid role="domainname">example.org</hostid> domain, you will
            have to refer to it by the fully-qualified domain name, <hostid
            role="fqdn">mumble.example.org</hostid>, instead of just
            <hostid>mumble</hostid>.</para>

          <para>Traditionally, this was allowed by BSD BIND resolvers.
            However the current version of
            <application>bind</application> (see &man.named.8;)
            that ships with FreeBSD no longer provides default
            abbreviations for non-fully qualified domain names other than
            the domain you are in. So an unqualified host
            <hostid>mumble</hostid> must either be found as <hostid
            role="fqdn">mumble.foo.example.org</hostid>, or it will be searched
            for in the root domain.</para>

          <para>This is different from the previous behavior, where the
            search continued across
            <hostid role="domainname">mumble.example.org</hostid>, and
            <hostid role="domainname">mumble.edu</hostid>.  Have a look at
            RFC 1535 for why this was considered bad practice, or even a
            security hole.</para>

          <para>As a good workaround, you can place the line</para>

          <programlisting>search foo.example.org example.org</programlisting>

          <para>instead of the previous</para>

          <programlisting>domain foo.example.org</programlisting>

          <para>into your
            <filename>/etc/resolv.conf</filename> file (see &man.resolv.conf.5;).  However, make sure that the
            search order does not go beyond the <quote>boundary between
            local and public administration</quote>, as RFC 1535 calls
            it.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="network-permission-denied">
          <para>Why do I get an error, <errorname>Permission denied</errorname>,
            for all networking operations?</para>
        </question>

        <answer>
          <para>If you have compiled your kernel with the
            <literal>IPFIREWALL</literal> option, you need to be aware
            that the default policy as of 2.1.7R (this actually changed
            during 2.1-STABLE development) is to deny all packets that are
            not explicitly allowed.</para>

          <para>If you had unintentionally misconfigured your system for
            firewalling, you can restore network operability by typing
            the following while logged in as <username>root</username>:</para>

          <screen>&prompt.root; <userinput>ipfw add 65534 allow all from any to any</userinput></screen>

          <para>You can also set <literal>firewall_type="open"</literal>
            in <filename>/etc/rc.conf</filename>.</para>

          <para>For further information on configuring a FreeBSD firewall,
            see the <ulink URL="../handbook/firewalls.html">
            Handbook section</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ipfw-overhead">
          <para>How much overhead does IPFW incur?</para>
        </question>

        <answer>
          <para>Please see the Handbook's <ulink
            url="../handbook/firewalls.html">Firewalls</ulink>
            section, specifically the section on <ulink
            url="../handbook/firewalls.html#IPFW-OVERHEAD">IPFW
            Overhead & Optimization</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ipfw-fwd">
          <para>Why is my <command>ipfw</command> <quote>fwd</quote> rule
            to redirect a service to another machine not working?</para>
        </question>

        <answer>
          <para>Possibly because you want to do network address translation
            (NAT) and not just forward packets.  A <quote>fwd</quote> rule
            does exactly what it says; it forwards packets.  It does not
            actually change the data inside the packet.  Say we have a rule
            like:</para>

          <screen>01000 fwd <replaceable>10.0.0.1</replaceable> from any to <replaceable>foo 21</replaceable></screen>

          <para>When a packet with a destination address of
            <replaceable>foo</replaceable> arrives at the machine with this
            rule, the packet is forwarded to
            <replaceable>10.0.0.1</replaceable>, but it still has the
            destination address of <replaceable>foo</replaceable>!  The
            destination address of the packet is <emphasis>not</emphasis>
            changed to <replaceable>10.0.0.1</replaceable>.  Most machines
            would probably drop a packet that they receive with a
            destination address that is not their own.  Therefore, using a
            <quote>fwd</quote> rule does not often work the way the user
            expects.  This behavior is a feature and not a bug.</para>

          <para>See the <link linkend="service-redirect">FAQ about
            redirecting services</link>, the &man.natd.8; manual, or one of
            the several port redirecting utilities in the <ulink
            url="../../../../ports/index.html">ports collection</ulink> for a correct way to do
            this.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="service-redirect">
          <para>How can I redirect service requests from one machine to
            another?</para>
        </question>

        <answer>
          <para>You can redirect FTP (and other service) request with
            the <literal>socket</literal> package, available in the ports
            tree in category <quote>sysutils</quote>. Simply replace the
            service's command line to call socket instead, like so:</para>

          <programlisting>ftp stream tcp nowait nobody /usr/local/bin/socket socket <replaceable>ftp.example.com</replaceable> <replaceable>ftp</replaceable></programlisting>

          <para>where <replaceable>ftp.example.com</replaceable> and
            <replaceable>ftp</replaceable> are the host and port to
            redirect to, respectively.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="bandwidth-mgr-tool">
          <para>Where can I get a bandwidth management tool?</para>
        </question>

        <answer>
          <para>There are three bandwidth management tools available for
	    FreeBSD.  &man.dummynet.4; is integrated into FreeBSD (or more
	    specifically, &man.ipfw.4;); <ulink
	    URL="http://www.csl.sony.co.jp/person/kjc/programs.html">ALTQ</ulink>
	    is available for free; Bandwidth Manager from <ulink
	    URL="http://www.etinc.com/">Emerging Technologies</ulink> is a
	    commercial product.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="bpf-not-configured">
          <para>Why do I get <errorname>/dev/bpf0: device not
            configured</errorname>?</para>
        </question>

        <answer>
          <para>You are running a program that requires the Berkeley
            Packet Filter (&man.bpf.4;), but it's not in your kernel.
            Add this to your kernel config file and build a new
            kernel:</para>

          <programlisting>pseudo-device bpf        # Berkeley Packet Filter</programlisting>

          <para>After rebooting, create the device node. This can be
            accomplished by going to the <filename>/dev</filename>
            directory and running:</para>

          <screen>&prompt.root; <userinput>sh MAKEDEV bpf0</userinput></screen>

          <para>Please see the <ulink
            URL="../handbook/kernelconfig-nodes.html"> Handbook entry
            on device nodes</ulink> for more information on creating
            devices.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="mount-smb-share">
          <para>How do I mount a disk from a Windows machine that is on my
            network, like smbmount in Linux?</para>
        </question>

        <answer>
          <para>Use the <application>SMBFS</application> toolset.  It
            includes a set of kernel modifications and a set of
            userland programs.  The programs and information are
            available as <filename role="package">net/smbfs</filename> in the ports
            collection, or in the base system as of 4.5-RELEASE and
            later.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="icmp-response-bw-limit">
          <para>What are these messages about <quote>icmp-response
            bandwidth limit 300/200 pps</quote> in my log
            files?</para>
        </question>

        <answer>
          <para>This is the kernel telling you that some activity is
            provoking it to send more ICMP or TCP reset (RST)
            responses than it thinks it should.  ICMP responses are
            often generated as a result of attempted connections to
            unused UDP ports.  TCP resets are generated as a result of
            attempted connections to unopened TCP ports.  Among
            others, these are the kinds of activities which may cause
            these messages:</para>

          <itemizedlist>
            <listitem>
              <para>Brute-force denial of service (DoS) attacks (as
                opposed to single-packet attacks which exploit a
                specific vulnerability).</para>
            </listitem>

            <listitem>
              <para>Port scans which attempt to connect to a large
                number of ports (as opposed to only trying a few
                well-known ports).</para>
            </listitem>
          </itemizedlist>

          <para>The first number in the message tells you how many
            packets the kernel would have sent if the limit was not in
            place, and the second number tells you the limit.  You can
            control the limit using the
            <varname>net.inet.icmp.icmplim</varname> sysctl variable
            like this, where <literal>300</literal> is the limit in
            packets per second:</para>

          <screen>&prompt.root; <userinput>sysctl -w net.inet.icmp.icmplim=300</userinput></screen>

          <para>If you do not want to see messages about this in your
            log files, but you still want the kernel to do response
            limiting, you can use the
            <varname>net.inet.icmp.icmplim_output</varname> sysctl
            variable to disable the output like this:</para>

          <screen>&prompt.root; <userinput>sysctl -w net.inet.icmp.icmplim_output=0</userinput></screen>

          <para>Finally, if you want to disable response limiting, you
            can set the <varname>net.inet.icmp.icmplim</varname>
            sysctl variable (see above for an example) to
            <literal>0</literal>.  Disabling response limiting is
            discouraged for the reasons listed above.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="unknown-hw-addr-format">
          <para>What are these <errorname>arp: unknown hardware
            address format</errorname> error messages?</para>
        </question>

        <answer>
          <para>This means that some device on your local Ethernet is
            using a MAC address in a format that FreeBSD does not
            recognize.  This is probably caused by someone
            experimenting with an Ethernet card somewhere else on the
            network.  You will see this most commonly on cable modem
            networks.  It is harmless, and should not affect the
            performance of your FreeBSD machine.</para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="security">
    <title>Security</title>
    <qandaset>
      <qandaentry>
        <question id="extra-named-port">
	  <para>BIND (<command>named</command>) is listening on port 53 and
	    some other high-numbered port.  What is going on?</para>
	</question>

	<answer>
	  <para>FreeBSD 3.0 and later use a version of BIND
	    that uses a random high-numbered port for outgoing queries.  If
	    you want to use port 53 for outgoing queries, either to get
	    past a firewall or to make yourself feel better, you can try
	    the following in
	    <filename>/etc/namedb/named.conf</filename>:</para>

	  <programlisting>options {
        query-source address * port 53;
};</programlisting>

	  <para>You can replace the <literal>*</literal> with a single IP
	    address if you want to tighten things further.</para>

	  <para>Congratulations, by the way.  It is good practice to read
	    your &man.sockstat.1; output and notice odd
	    things!</para>
	</answer>
      </qandaentry>

      <qandaentry>
        <question id="sendmail-port-587">
          <para>Sendmail is listening on port 587 as well as the
            standard port 25! What is going on?</para>
        </question>

        <answer>
          <para>Recent versions of Sendmail support a
            mail submission feature that runs over port 587.  This is
            not yet widely supported, but is growing in
            popularity.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="toor-account">
          <para>What is this UID 0 <username>toor</username> account? Have I
            been compromised?</para>
        </question>

        <answer>
          <para>Do not worry. <username>toor</username> is an
            <quote>alternative</quote> superuser account (toor is root
            spelt backwards). Previously it was created when the
            &man.bash.1; shell was installed but now it is created by
            default. It is intended to be used with a non-standard shell so
            you do not have to change <username>root</username>'s default
            shell. This is important as shells which are not part of the
            base distribution (for example a shell installed from ports or
            packages) are likely be to be installed in
            <filename>/usr/local/bin</filename> which, by default, resides
            on a different filesystem. If <username>root</username>'s shell
            is located in <filename>/usr/local/bin</filename> and
            <filename>/usr</filename> (or whatever filesystem contains
            <filename>/usr/local/bin</filename>) is not mounted for some
            reason, <username>root</username> will not be able to log in to
            fix a problem (although if you reboot into single user mode
            you will be prompted for the path to a shell).</para>

          <para>Some people use <username>toor</username> for
            day-to-day root tasks with a non-standard shell, leaving
            <username>root</username>, with a standard shell, for
            single user mode or emergencies. By default you cannot log
            in using <username>toor</username> as it does not have a
            password, so log in as <username>root</username> and set a password for
            <username>toor</username> if you want to use it.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="suidperl">
          <para>Why is <command>suidperl</command> not working
            properly?</para>
        </question>

        <answer>
          <para>For security reasons, <command>suidperl</command> is
            installed without the suid bit by default.  The system
            administrator can enable suid behavior with the following
            command.</para>

	    <screen>&prompt.root; <userinput>chmod u+s /usr/bin/suidperl</userinput></screen>

          <para>If you want <command>suidperl</command> to be built
            suid during upgrades from source, edit
            <filename>/etc/make.conf</filename> and add
            <varname>ENABLE_SUIDPERL=true</varname> before you run
            <command>make buildworld</command>.</para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="ppp">
    <title>PPP</title>

    <qandaset>
      <qandaentry>
        <question id="userppp">
          <para>I cannot make &man.ppp.8; work.  What am I doing wrong?</para>
        </question>

        <answer>
          <para>You should first read the
            &man.ppp.8;
            man page and the <ulink
            URL="../handbook/ppp-and-slip.html#USERPPP">
            PPP section of the handbook</ulink>.  Enable logging with
            the command</para>

          <programlisting>set log Phase Chat Connect Carrier lcp ipcp ccp command</programlisting>

          <para>This command may be typed at the
            &man.ppp.8; command prompt or it may be
            entered in the <filename>/etc/ppp/ppp.conf</filename>
            configuration file (the start of the
            <literal>default</literal> section is the best
            place to put it).  Make sure that
            <filename>/etc/syslog.conf</filename> (see &man.syslog.conf.5;) contains the lines</para>

          <programlisting>!ppp
*.*        /var/log/ppp.log</programlisting>

          <para>and that the file <filename>/var/log/ppp.log</filename>
            exists.  You can now find out a lot about what is going on
            from the log file.  Do not worry if it does not all make sense.
            If you need to get help from someone, it may make sense to
            them.</para>

          <para>If your version of &man.ppp.8; does not understand the
            <command>set log</command> command, you should download the
            <ulink URL="http://people.FreeBSD.org/~brian/">
            latest version</ulink>. It will build on FreeBSD version
            2.1.5 and higher.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-hangs">
          <para>Why does &man.ppp.8; hang when I run it?</para>
        </question>

        <answer>
          <para>This is usually because your hostname will not resolve.
            The best way to fix this is to make sure that
            <filename>/etc/hosts</filename> is consulted by your
            resolver first by editing <filename>/etc/host.conf</filename>
            and putting the <literal>hosts</literal> line first.  Then,
            simply put an entry in <filename>/etc/hosts</filename> for
            your local machine.  If you have no local network, change your
            <hostid>localhost</hostid> line:</para>

          <programlisting>127.0.0.1        foo.bar.com foo localhost</programlisting>

          <para>Otherwise, simply add another entry for your host.
            Consult the relevant man pages for more details.</para>

          <para>You should be able to successfully
            <command>ping -c1 `hostname`</command> when you are done.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-nodial-auto">
          <para>Why will &man.ppp.8; not dial in <literal>-auto</literal>
            mode?</para>
        </question>

        <answer>
          <para>First, check that you have got a default route.  By running
            <command>netstat -rn</command> (see &man.netstat.1;), you should see two entries like this:</para>

          <programlisting>Destination        Gateway            Flags     Refs     Use     Netif Expire
default            10.0.0.2           UGSc        0        0      tun0
10.0.0.2           10.0.0.1           UH          0        0      tun0</programlisting>

          <para>This is assuming that you have used the addresses from the
            handbook, the man page or from the ppp.conf.sample file.
            If you do not have a default route, it may be because you are
            running an old version of &man.ppp.8;
            that does not understand the word <literal>HISADDR</literal>
            in the ppp.conf file.  If your version of
            &man.ppp.8; is from before FreeBSD
            2.2.5, change the</para>

          <programlisting>add 0 0 HISADDR</programlisting>

          <para>line to one saying</para>


          <programlisting>add 0 0 10.0.0.2</programlisting>

          <para>Another reason for the default route line being missing
            is that you have mistakenly set up a default router in your
            <filename>/etc/rc.conf</filename> (see &man.rc.conf.5;) file (this file was called
            <filename>/etc/sysconfig</filename> prior to release 2.2.2),
            and you have omitted the line saying</para>

          <programlisting>delete ALL</programlisting>

          <para>from <filename>ppp.conf</filename>.  If this is the case,
            go back to the <ulink
            URL="../handbook/ppp-and-slip.html#USERPPP-FINAL">
            Final system configuration</ulink> section of the
            handbook.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="no-route-to-host">
          <para>What does <errorname>No route to host</errorname> mean?</para>
        </question>

        <answer>
          <para>This error is usually due to a missing</para>

          <programlisting>MYADDR:
  delete ALL
  add 0 0 HISADDR</programlisting>

          <para>section in your <filename>/etc/ppp/ppp.linkup</filename>
            file.  This is only necessary if you have a dynamic IP address
            or do not know the address of your gateway.  If you are using
            interactive mode, you can type the following after entering
            <literal>packet mode</literal> (packet mode is
            indicated by the capitalized <acronym>PPP</acronym> in the
            prompt):</para>

         <programlisting>delete ALL
add 0 0 HISADDR</programlisting>

          <para>Refer to the <ulink
            URL="../handbook/ppp-and-slip.html#USERPPP-DYNAMICIP">
            PPP and Dynamic IP addresses</ulink> section of the handbook
            for further details.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="connection-threeminutedrop">
          <para>Why does my connection drop after about 3 minutes?</para>
        </question>

        <answer>
          <para>The default PPP timeout is 3 minutes.  This can be
            adjusted with the line</para>

          <programlisting>set timeout <replaceable>NNN</replaceable></programlisting>

          <para>where <replaceable>NNN</replaceable> is the number of
            seconds of inactivity before the connection is closed.  If
            <replaceable>NNN</replaceable> is zero, the connection is never
            closed due to a timeout. It is possible to put this command in
            the <filename>ppp.conf</filename> file, or to type it at the
            prompt in interactive mode. It is also possible to adjust it on
            the fly while the line is active by connecting to
            <application>ppp</application>s server socket using
            &man.telnet.1; or &man.pppctl.8;.
            Refer to the
            &man.ppp.8; man
            page for further details.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-drop-heavy-load">
          <para>Why does my connection drop under heavy load?</para>
        </question>

        <answer>
          <para>If you have Link Quality Reporting (LQR) configured,
            it is possible that too many LQR packets are lost between
            your machine and the peer.  Ppp deduces that the line must
            therefore be bad, and disconnects.  Prior to FreeBSD version
            2.2.5, LQR was enabled by default.  It is now disabled by
            default. LQR can be disabled with the line</para>

          <programlisting>disable lqr</programlisting>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-drop-random">
          <para>Why does my connection drop after a random amount of
            time?</para>
        </question>

        <answer>
          <para>Sometimes, on a noisy phone line or even on a line with
            call waiting enabled, your modem may hang up because it
            thinks (incorrectly) that it lost carrier.</para>

          <para>There is a setting on most modems for determining how
            tolerant it should be to temporary losses of carrier.  On a
            USR Sportster for example, this is measured by the S10
            register in tenths of a second.  To make your modem more
            forgiving, you could add the following send-expect sequence
            to your dial string:</para>

          <programlisting>set dial "...... ATS10=10 OK ......"</programlisting>

          <para>Refer to your modem manual for details.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-hangs-random">
          <para>Why does my connection hang after a random amount of
            time?</para>
        </question><answer>

          <para>Many people experience hung connections with no apparent
            explanation.  The first thing to establish is which side of
            the link is hung.</para>

          <para>If you are using an external modem, you can simply try
            using &man.ping.8; to see if the
            <acronym>TD</acronym> light is flashing when you transmit data.
            If it flashes (and the <acronym>RD</acronym> light does not),
            the problem is with the remote end. If <acronym>TD</acronym>
            does not flash, the problem is local. With an internal modem,
            you will need to use the <literal>set server</literal> command in
            your <filename>ppp.conf</filename> file. When the hang occurs,
            connect to &man.ppp.8; using &man.pppctl.8;. If your network connection
            suddenly revives (PPP was revived due to the activity on the
            diagnostic socket) or if you cannot connect (assuming the
            <literal>set socket</literal> command succeeded at startup
            time), the problem is local. If you can connect and things are
            still hung, enable local async logging with <literal>set log
            local async</literal> and use &man.ping.8; from
            another window or terminal to make use of the link. The async
            logging will show you the data being transmitted and received
            on the link. If data is going out and not coming back, the
            problem is remote.</para>

          <para>Having established whether the problem is local or remote,
            you now have two possibilities:</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-remote-not-responding">
          <para>The remote end is not responding.  What can I do?</para>
        </question>

        <answer>
          <para>There is very little you can do about this.  Most ISPs
            will refuse to help if you are not running a Microsoft OS.
            You can <literal>enable lqr</literal> in your
            <filename>ppp.conf</filename> file, allowing &man.ppp.8; to detect
            the remote failure and hang up, but this detection is
            relatively slow and therefore not that useful.  You may want to
            avoid telling your ISP that you are running user-PPP...</para>

          <para>First, try disabling all local compression by adding the
            following to your configuration:</para>

          <programlisting>disable pred1 deflate deflate24 protocomp acfcomp shortseq vj
deny pred1 deflate deflate24 protocomp acfcomp shortseq vj</programlisting>

          <para>Then reconnect to ensure that this makes no difference.
            If things improve or if the problem is solved completely,
            determine which setting makes the difference through trial
            and error.  This will provide good ammunition when you contact
            your ISP (although it may make it apparent that you are not
            running a Microsoft product).</para>

          <para>Before contacting your ISP, enable async logging locally
            and wait until the connection hangs again.  This may use up
            quite a bit of disk space.  The last data read from the port
            may be of interest.  It is usually ascii data, and may even
            describe the problem
            (<quote>Memory fault, core dumped</quote>?).</para>

          <para>If your ISP is helpful, they should be able to enable
            logging on their end, then when the next link drop occurs,
            they may be able to tell you why their side is having a
            problem.  Feel free to send the details to &a.brian;, or
            even to ask your ISP to contact me directly.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-hung">
          <para>&man.ppp.8; has hung.  What can I do?</para>
        </question>

        <answer>
          <para>Your best bet here is to rebuild &man.ppp.8; by adding
            <literal>CFLAGS+=-g</literal> and <literal>STRIP=</literal>
            to the end of the Makefile, then doing a
            <command>make clean &amp;&amp; make &amp;&amp; make
            install</command>.  When &man.ppp.8; hangs, find the &man.ppp.8; process id
            with <command>ps ajxww | fgrep ppp</command> and run
            <command>gdb ppp <replaceable>PID</replaceable></command>.
            From the gdb prompt, you can then use <command>bt</command>
            to get a stack trace.</para>

          <para>Send the results to <email>brian@Awfulhak.org</email>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-loginok-thennothing">
          <para>Why does nothing happen after the <quote>Login OK!</quote>
            message?</para>
        </question>

        <answer>
          <para>Prior to FreeBSD version 2.2.5, once the link was
            established, &man.ppp.8;
            would wait for the peer to initiate the Line Control Protocol
            (LCP).  Many ISPs will not initiate negotiations and expect
            the client to do so.  To force
            &man.ppp.8; to initiate the LCP, use the
            following line:</para>

          <programlisting>set openmode active</programlisting>

            <note>
              <para>It usually does no
            harm if both sides initiate negotiation, so openmode is now
            active by default.  However, the next section explains when
            it <emphasis>does</emphasis> do some harm.</para>
            </note>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-same-magic">
          <para>I keep seeing errors about magic being the same.  What does
            it mean?</para>
        </question>

        <answer>
          <para>Occasionally, just after connecting, you may see messages
            in the log that say <quote>magic is the same</quote>.
            Sometimes, these messages are harmless, and sometimes one side
            or the other exits.  Most PPP implementations cannot survive
            this problem, and even if the link seems to come up, you will see
            repeated configure requests and configure acknowledgments in
            the log file until &man.ppp.8; eventually gives up and closes the
            connection.</para>

          <para>This normally happens on server machines with slow disks
            that are spawning a getty on the port, and executing &man.ppp.8; from
            a login script or program after login.  I have also heard reports
            of it happening consistently when using slirp.  The reason is
            that in the time taken between &man.getty.8; exiting and &man.ppp.8; starting,
            the client-side &man.ppp.8; starts sending Line Control Protocol (LCP)
            packets.  Because ECHO is still switched on for the port on
            the server, the client &man.ppp.8; sees these packets
            <quote>reflect</quote> back.</para>

          <para>One part of the LCP negotiation is to establish a magic
            number for each side of the link so that
            <quote>reflections</quote> can be detected. The protocol says
            that when the peer tries to negotiate the same magic number, a
            NAK should be sent and a new magic number should be chosen.
            During the period that the server port has ECHO turned on, the
            client &man.ppp.8; sends LCP packets, sees the same magic in the
            reflected packet and NAKs it. It also sees the NAK reflect
            (which also means &man.ppp.8; must change its magic). This produces a
            potentially enormous number of magic number changes, all of
            which are happily piling into the server's tty buffer. As soon
            as &man.ppp.8; starts on the server, it is flooded with magic number
            changes and almost immediately decides it has tried enough to
            negotiate LCP and gives up. Meanwhile, the client, who no
            longer sees the reflections, becomes happy just in time to see
            a hangup from the server.</para>

          <para>This can be avoided by allowing the peer to start
            negotiating with the following line in your ppp.conf
            file:</para>

          <programlisting>set openmode passive</programlisting>

          <para>This tells &man.ppp.8; to wait for the server to initiate LCP
            negotiations.  Some servers however may never initiate
            negotiations.  If this is the case, you can do something
            like:</para>

          <programlisting>set openmode active 3</programlisting>

          <para>This tells &man.ppp.8; to be passive for 3 seconds, and then to
            start sending LCP requests.  If the peer starts sending
            requests during this period, &man.ppp.8; will immediately respond
            rather than waiting for the full 3 second period.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-lcp-constant">
          <para>LCP negotiations continue until the connection is
            closed.  What is wrong?</para>
        </question>

        <answer>
          <para>There is currently an implementation mis-feature in
            &man.ppp.8; where it does not associate
            LCP, CCP &amp; IPCP responses with their original requests. As
            a result, if one PPP
            implementation is more than 6 seconds slower than the other
            side, the other side will send two additional LCP configuration
            requests. This is fatal.</para>

          <para>Consider two implementations,
            <hostid>A</hostid> and
            <hostid>B</hostid>. <hostid>A</hostid> starts
            sending LCP requests immediately after connecting and
            <hostid>B</hostid> takes 7 seconds to start. When
            <hostid>B</hostid> starts, <hostid>A</hostid>
            has sent 3 LCP REQs. We are assuming the line has ECHO switched
            off, otherwise we would see magic number problems as described in
            the previous section. <hostid>B</hostid> sends a
            REQ, then an ACK to the first of
            <hostid>A</hostid>'s REQs. This results in
            <hostid>A</hostid> entering the <acronym>OPENED</acronym>
            state and sending and ACK (the first) back to
            <hostid>B</hostid>. In the meantime,
            <hostid>B</hostid> sends back two more ACKs in response to
            the two additional REQs sent by <hostid>A</hostid>
            before <hostid>B</hostid> started up.
            <hostid>B</hostid> then receives the first ACK from
            <hostid>A</hostid> and enters the
            <acronym>OPENED</acronym> state.
            <hostid>A</hostid> receives the second ACK from
            <hostid>B</hostid> and goes back to the
            <acronym>REQ-SENT</acronym> state, sending another (forth) REQ
            as per the RFC. It then receives the third ACK and enters the
            <acronym>OPENED</acronym> state. In the meantime,
            <hostid>B</hostid> receives the forth REQ from
            <hostid>A</hostid>, resulting in it reverting to the
            <acronym>ACK-SENT</acronym> state and sending
            another (second) REQ and (forth) ACK as per the RFC.
            <hostid>A</hostid> gets the REQ, goes into
            <acronym>REQ-SENT</acronym> and sends another REQ. It
            immediately receives the following ACK and enters
            <acronym>OPENED</acronym>.</para>

          <para>This goes on until one side figures out that they are
            getting nowhere and gives up.</para>

          <para>The best way to avoid this is to configure one side to be
            <literal>passive</literal> - that is, make one side
            wait for the other to start negotiating.  This can be done
            with the</para>

          <programlisting>set openmode passive</programlisting>

          <para>command.  Care should be taken with this option.  You
            should also use the</para>

          <programlisting>set stopped N</programlisting>

          <para>command to limit the amount of time that
            &man.ppp.8; waits for the peer to begin
            negotiations.  Alternatively, the</para>

          <programlisting>set openmode active N</programlisting>

          <para>command (where <replaceable>N</replaceable> is the
            number of seconds to wait before starting negotiations) can be
            used.  Check the manual page for details.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-lockups">
          <para>Why does &man.ppp.8; lock up shortly after connection?</para>
        </question>

        <answer>
          <para>Prior to version 2.2.5 of FreeBSD, it was possible that
            your link was disabled shortly after connection due to
            &man.ppp.8; mis-handling Predictor1
            compression negotiation. This would only happen if both sides
            tried to negotiate different Compression Control Protocols
            (CCP). This problem is now corrected, but if you are still
            running an old version of &man.ppp.8;
            the problem can be circumvented with the line</para>

          <programlisting>disable pred1</programlisting>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-shell-test-lockup">
          <para>Why does &man.ppp.8; lock up when I shell out to test it?</para>
        </question>

        <answer>
          <para>When you execute the <command>shell</command> or
            <command>!</command> command, &man.ppp.8; executes a
            shell (or if you have passed any arguments,
            &man.ppp.8; will execute those arguments). Ppp will
            wait for the command to complete before continuing. If you
            attempt to use the PPP link while running the command, the link
            will appear to have frozen. This is because
            &man.ppp.8; is waiting for the command to
            complete.</para>

          <para>If you wish to execute commands like this, use the
            <command>!bg</command> command instead.  This will execute
            the given command in the background, and &man.ppp.8; can continue to
            service the link.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-nullmodem">
          <para>Why does &man.ppp.8; over a null-modem cable never exit?</para>
        </question>

        <answer>
          <para>There is no way for &man.ppp.8; to
            automatically determine that a direct connection has been
            dropped.  This is due to the lines that are used in a
            null-modem serial cable.  When using this sort of connection,
            LQR should always be enabled with the line</para>

          <programlisting>enable lqr</programlisting>

          <para>LQR is accepted by default if negotiated by the peer.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-auto-noreasondial">
          <para>Why does &man.ppp.8; dial for no reason in -auto mode?</para>
        </question><answer>

          <para>If &man.ppp.8; is dialing
            unexpectedly, you must determine the cause, and set up Dial
            filters (dfilters) to prevent such dialing.</para>

          <para>To determine the cause, use the following line:</para>

          <programlisting>set log +tcp/ip</programlisting>

          <para>This will log all traffic through the connection.  The
            next time the line comes up unexpectedly, you will see the
            reason logged with a convenient timestamp next to it.</para>

          <para>You can now disable dialing under these circumstances.
            Usually, this sort of problem arises due to DNS lookups.  To
            prevent DNS lookups from establishing a connection (this will
            <emphasis>not</emphasis> prevent
            &man.ppp.8; from passing the packets
            through an established connection), use the following:</para>

          <programlisting>set dfilter 1 deny udp src eq 53
set dfilter 2 deny udp dst eq 53
set dfilter 3 permit 0/0 0/0</programlisting>

          <para>This is not always suitable, as it will effectively break
            your demand-dial capabilities - most programs will need a DNS
            lookup before doing any other network related things.</para>

          <para>In the DNS case, you should try to determine what is
            actually trying to resolve a host name.  A lot of the time,
            &man.sendmail.8; is the culprit.  You should make sure that
            you tell sendmail not to do any DNS lookups in its
            configuration file.  See the section on
            <link linkend="ispmail">Mail Configuration</link> for details
            on how to create your own configuration file and what should
            go into it.  You may also want to add the following line to
            your <filename>.mc</filename> file:</para>

          <programlisting>define(`confDELIVERY_MODE', `d')dnl</programlisting>

          <para>This will make sendmail queue everything until the queue
            is run (usually, sendmail is invoked with
            <option>-bd -q30m</option>, telling it to run the queue every
            30 minutes) or until a <command>sendmail -q</command> is done
            (perhaps from your ppp.linkup file).</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ccp-errors">
          <para>What do these CCP errors mean?</para>
        </question>

        <answer>
          <para>I keep seeing the following errors in my log file:</para>

          <programlisting>CCP: CcpSendConfigReq
CCP: Received Terminate Ack (1) state = Req-Sent (6)</programlisting>

          <para>This is because &man.ppp.8; is trying to negotiate Predictor1
            compression, and the peer does not want to negotiate any
            compression at all.  The messages are harmless, but if you
            wish to remove them, you can disable Predictor1 compression
            locally too:</para>

          <programlisting>disable pred1</programlisting>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-lockup-ioerrors">
          <para>Why does &man.ppp.8; lock up during file transfers with IO
            errors?</para>
        </question>

        <answer>
          <para>Under FreeBSD 2.2.2 and before, there was a bug in the
            tun driver that prevents incoming packets of a size larger
            than the tun interface's MTU size.  Receipt of a packet
            greater than the MTU size results in an IO error being logged
            via syslogd.</para>

          <para>The PPP specification says that an MRU of 1500 should
            <emphasis>always</emphasis> be accepted as a minimum,
            despite any LCP negotiations, therefore it is possible that
            should you decrease the MTU to less than 1500, your ISP will
            transmit packets of 1500 regardless, and you will tickle this
            non-feature - locking up your link.</para>

          <para>The problem can be circumvented by never setting an MTU of
            less than 1500 under FreeBSD 2.2.2 or before.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-connectionspeed">
          <para>Why does &man.ppp.8; not log my connection speed?</para>
        </question>

        <answer>

          <para>In order to log all lines of your modem
            <quote>conversation</quote>, you must enable the
            following:</para>

          <programlisting>set log +connect</programlisting>

          <para>This will make &man.ppp.8; log
            everything up until the last requested <quote>expect</quote>
            string.</para>

          <para>If you wish to see your connect speed and are using PAP
            or CHAP (and therefore do not have anything to
            <quote>chat</quote> after the CONNECT in the dial script - no
            <literal>set login</literal> script), you must make sure that
            you instruct &man.ppp.8; to <quote>expect</quote> the whole CONNECT
            line, something like this:</para>

          <programlisting>set dial "ABORT BUSY ABORT NO\\sCARRIER TIMEOUT 4 \
  \"\" ATZ OK-ATZ-OK ATDT\\T TIMEOUT 60 CONNECT \\c \\n"</programlisting>

          <para>Here, we get our CONNECT, send nothing, then expect a
            line-feed, forcing &man.ppp.8; to read
            the whole CONNECT response.</para>

        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-ignores-backslash">
          <para>Why does &man.ppp.8; ignore the <literal>\</literal> character
            in my chat script?</para>
        </question><answer>

          <para>Ppp parses each line in your config files so that it can
            interpret strings such as
            <literal>set phone "123 456 789"</literal> correctly (and
            realize that the number is actually only
            <emphasis>one</emphasis> argument. In order to specify a
            <literal>&quot;</literal> character, you must escape it
            using a backslash (<literal>\</literal>).</para>

          <para>When the chat interpreter parses each argument, it
            re-interprets the argument in order to find any special
            escape sequences such as <literal>\P</literal> or
            <literal>\T</literal> (see the man page).  As a result of this
            double-parsing, you must remember to use the correct number of
            escapes.</para>

          <para>If you wish to actually send a <literal>\</literal>
            character to (say) your modem, you would need something
            like:</para>

          <programlisting>set dial "\"\" ATZ OK-ATZ-OK AT\\\\X OK"</programlisting>

          <para>resulting in the following sequence:</para>

          <programlisting>ATZ
OK
AT\X
OK</programlisting>

          <para>or</para>

          <programlisting>set phone 1234567
set dial "\"\" ATZ OK ATDT\\T"</programlisting>

          <para>resulting in the following sequence:</para>

          <programlisting>ATZ
OK
ATDT1234567</programlisting>

        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-segfault-nocore">
          <para>Why does &man.ppp.8; get a seg-fault, but I see no
            <filename>ppp.core</filename> file?</para>
        </question>

        <answer>
          <para>Ppp (or any other program for that matter) should never
            dump core.  Because &man.ppp.8; runs with an effective user id of 0,
            the operating system will not write &man.ppp.8;'s core image to disk
            before terminating it.  If, however &man.ppp.8;
            is actually terminating due to a
            segmentation violation or some other signal that normally
            causes core to be dumped, <emphasis>and</emphasis>
            you are sure you are using the latest version (see the start of
            this section), then you should do the following:</para>

          <screen>&prompt.user; <userinput>tar xfz ppp-*.src.tar.gz</userinput>
&prompt.user; <userinput>cd ppp*/ppp</userinput>
&prompt.user; <userinput>echo STRIP= &gt;&gt;Makefile</userinput>
&prompt.user; <userinput>echo CFLAGS+=-g &gt;&gt;Makefile</userinput>
&prompt.user; <userinput>make clean all</userinput>
&prompt.user; <userinput>su</userinput>
&prompt.root; <userinput>make install</userinput>
&prompt.root; <userinput>chmod 555 /usr/sbin/ppp</userinput></screen>

          <para>You will now have a debuggable version of &man.ppp.8; installed.
            You will have to be <username>root</username> to run &man.ppp.8; as all of its privileges
            have been revoked.  When you start &man.ppp.8;, take a careful note
            of what your current directory was at the time.</para>

          <para>Now, if and when &man.ppp.8; receives the segmentation violation,
            it will dump a core file called <filename>ppp.core</filename>.  You should then do
            the following:</para>

          <screen>&prompt.user; <userinput>su</userinput>
&prompt.root; <userinput>gdb /usr/sbin/ppp ppp.core</userinput>
<prompt>(gdb)</prompt> <userinput>bt</userinput>
.....
<prompt>(gdb)</prompt> <userinput>f 0</userinput>
....
<prompt>(gdb)</prompt> <userinput>i args</userinput>
....
<prompt>(gdb)</prompt> <userinput>l</userinput>
.....</screen>

          <para>All of this information should be given alongside your
            question, making it possible to diagnose the problem.</para>

          <para>If you are familiar with gdb, you may wish to find out some
            other bits and pieces such as what actually caused the dump and
            the addresses &amp; values of the relevant variables.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-autodialprocess-noconnect">
          <para>Why does the process that forces a dial in auto mode never
            connect?</para>
        </question>

        <answer>
          <para>This was a known problem with
            &man.ppp.8; set up to negotiate a
            dynamic local IP number with the peer in auto mode.  It is
            fixed in the latest version - search the man page for
            <literal>iface</literal>.</para>

          <para>The problem was that when that initial program calls
            &man.connect.2;, the IP number of the tun interface is assigned
            to the socket endpoint. The kernel creates the first outgoing
            packet and writes it to the tun device.
            &man.ppp.8; then reads the packet and
            establishes a connection. If, as a result of
            &man.ppp.8;'s dynamic IP assignment, the
            interface address is changed, the original socket endpoint will
            be invalid. Any subsequent packets sent to the peer will
            usually be dropped. Even if they are not, any responses will
            not route back to the originating machine as the IP number is
            no longer owned by that machine.</para>

          <para>There are several theoretical ways to approach this
            problem. It would be nicest if the peer would re-assign the
            same IP number if possible <literal>:-)</literal>
            The current version of &man.ppp.8; does
            this, but most other implementations do not.</para>

          <para>The easiest method from our side would be to never change
            the tun interface IP number, but instead to change all outgoing
            packets so that the source IP number is changed from the
            interface IP to the negotiated IP on the fly. This is
            essentially what the <literal>iface-alias</literal> option in
            the latest version of &man.ppp.8; is
            doing (with the help of
            &man.libalias.3; and &man.ppp.8;'s <option>-nat</option> switch) -
            it is maintaining all previous interface addresses and NATing
            them to the last negotiated address.</para>

          <para>Another alternative (and probably the most reliable) would
            be to implement a system call that changes all bound sockets
            from one IP to another.  &man.ppp.8; would
            use this call to modify the sockets of all existing programs
            when a new IP number is negotiated. The same system call could
            be used by dhcp clients when they are forced to re-bind() their
            sockets.</para>

          <para>Yet another possibility is to allow an interface to be
            brought up without an IP number. Outgoing packets would be
            given an IP number of 255.255.255.255 up until the first
            SIOCAIFADDR ioctl is done. This would result in fully binding
            the socket. It would be up to &man.ppp.8;
            to change the source IP number, but only if it is set to
            255.255.255.255, and only the IP number and IP checksum would
            need to change. This, however is a bit of a hack as the kernel
            would be sending bad packets to an improperly configured
            interface, on the assumption that some other mechanism is
            capable of fixing things retrospectively.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ppp-nat-games">
          <para>Why do most games not work with the -nat switch?</para>
        </question>

        <answer>
          <para>The reason games and the like do not work when libalias
            is in use is that the machine on the outside will try to open a
            connection or send (unsolicited) UDP packets to the machine on
            the inside. The NAT software does not know that it should send
            these packets to the interior machine.</para>

          <para>To make things work, make sure that the only thing
            running is the software that you are having problems with, then
            either run tcpdump on the tun interface of the gateway or
            enable &man.ppp.8; tcp/ip logging (<literal>set log +tcp/ip</literal>)
            on the gateway.</para>

          <para>When you start the offending software, you should see
            packets passing through the gateway machine. When something
            comes back from the outside, it will be dropped (that is the
            problem). Note the port number of these packets then shut down
            the offending software. Do this a few times to see if the port
            numbers are consistent. If they are, then the following line in
            the relevant section of <filename>/etc/ppp/ppp.conf</filename> will make the
            software functional:</para>

          <programlisting>nat port <replaceable>proto</replaceable> <replaceable>internalmachine</replaceable>:<replaceable>port</replaceable> <replaceable>port</replaceable></programlisting>

          <para>where <replaceable>proto</replaceable> is either
            <literal>tcp</literal> or <literal>udp</literal>,
            <replaceable>internalmachine</replaceable> is the machine that
            you want the packets to be sent to and
            <replaceable>port</replaceable> is the destination port number
            of the packets.</para>

          <para>You will not be able to use the software on other machines
            without changing the above command, and running the software
            on two internal machines at the same time is out of the question
            - after all, the outside world is seeing your entire internal
            network as being just a single machine.</para>

          <para>If the port numbers are not consistent, there are three
            more options:</para>

          <orderedlist>
            <listitem>
          <para>Submit support in
            libalias. Examples of <quote>special cases</quote> can be found
            in <filename>/usr/src/lib/libalias/alias_*.c</filename>
            (<filename>alias_ftp.c</filename> is a good prototype). This
            usually involves reading certain recognised outgoing packets,
            identifying the instruction that tells the outside machine to
            initiate a connection back to the internal machine on a
            specific (random) port and setting up a <quote>route</quote> in
            the alias table so that the subsequent packets know where to
            go.</para>

          <para>This is the most difficult solution, but it is the best
            and will make the software work with multiple machines.</para>
            </listitem>

            <listitem>
              <para>Use a proxy.  The
            application may support socks5 for example, or (as in the
            <quote>cvsup</quote> case) may have a <quote>passive</quote>
            option that avoids ever requesting that the peer open
            connections back to the local machine.</para>
            </listitem>

            <listitem>
          <para>Redirect everything to
            the internal machine using <literal>nat addr</literal>.  This
            is the sledge-hammer approach.</para>
            </listitem>
          </orderedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="useful-port-numbers">
          <para>Has anybody made a list of useful port numbers?</para>
        </question><answer>

          <para>Not yet, but this is intended to grow into such a list
            (if any interest is shown).  In each example,
            <replaceable>internal</replaceable> should be replaced with
            the IP number of the machine playing the game.</para>

          <itemizedlist>
            <listitem>
              <para><application>Asheron's Call</application></para>

              <para><literal>nat port udp
                <replaceable>internal</replaceable>
                :65000 65000</literal></para>

              <para>Manually change the port number within the game to
                65000. If you have got a number of machines that you wish
                to play on assign a unique port number for each (i.e.
                65001, 65002, etc) and add a <literal>nat port</literal>
                line for each one.</para>
            </listitem>

            <listitem>
              <para><application>Half Life</application></para>

              <para><literal>nat port udp
                <replaceable>internal</replaceable>:27005
                27015</literal></para>
            </listitem>

            <listitem>
              <para><application>PCAnywhere 8.0</application></para>

              <para><literal>nat port udp
                <replaceable>internal</replaceable>:5632
                5632</literal></para>

              <para><literal>nat port tcp
                <replaceable>internal</replaceable>:5631
                5631</literal></para>
            </listitem>

            <listitem>
              <para><application>Quake</application></para>

              <para><literal>nat port udp
                <replaceable>internal</replaceable>:6112
                6112</literal></para>

              <para>Alternatively, you may want to take a look at <ulink
                URL="http://www.battle.net/support/proxy/">
                www.battle.net</ulink> for Quake proxy support.</para>
            </listitem>

            <listitem>
              <para><application>Quake 2</application></para>

              <para><literal>nat port udp
                <replaceable>internal</replaceable>:27901
                27910</literal></para>
              <para><literal>nat port udp
                <replaceable>internal</replaceable>:60021
                60021</literal></para>
              <para><literal>nat port udp
                <replaceable>internal</replaceable>:60040
                60040</literal></para>
            </listitem>

            <listitem>
              <para><application>Red Alert</application></para>

              <para><literal>nat port udp
                <replaceable>internal</replaceable>:8675
                8675</literal></para>

              <para><literal>nat port udp
                <replaceable>internal</replaceable>:5009
                5009</literal></para>
            </listitem>
          </itemizedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="fcs-errors">
          <para>What are FCS errors?</para>
        </question>

        <answer>
          <para>FCS stands for <literal>F</literal>rame
            <literal>C</literal>heck
            <literal>S</literal>equence.  Each PPP packet
            has a checksum attached to ensure that the data being
            received is the data being sent.  If the FCS of an incoming
            packet is incorrect, the packet is dropped and the HDLC FCS
            count is increased.  The HDLC error values can be displayed
            using the <literal>show hdlc</literal> command.</para>

          <para>If your link is bad (or if your serial driver is dropping
            packets), you will see the occasional FCS error.  This is not
            usually worth worrying about although it does slow down the
            compression protocols substantially.  If you have an external
            modem, make sure your cable is properly shielded from
            interference - this may eradicate the problem.</para>

          <para>If your link freezes as soon as you have connected and you
            see a large number of FCS errors, this may be because your link
            is not 8 bit clean. Make sure your modem is not using software
            flow control (XON/XOFF). If your datalink
            <emphasis>must</emphasis> use software flow control, use the
            command <literal>set accmap 0x000a0000</literal> to tell
            &man.ppp.8; to escape the <literal>^Q</literal> and
            <literal>^S</literal> characters.</para>

          <para>Another reason for seeing too many FCS errors may be that
            the remote end has stopped talking <acronym>PPP</acronym>. You
            may want to enable <literal>async</literal> logging at this
            point to determine if the incoming data is actually a login or
            shell prompt. If you have a shell prompt at the remote end,
            it is possible to terminate &man.ppp.8; without dropping the line by
            using the <literal>close lcp</literal> command (a following
            <literal>term</literal> command will reconnect you to the shell
            on the remote machine.</para>

          <para>If nothing in your log file indicates why the link might
            have been terminated, you should ask the remote administrator
            (your ISP?) why the session was terminated.</para>
        </answer>
      </qandaentry>

      <qandaentry id=PPPoEwithNAT>
        <question id="macos-win98-pppoe-freeze">
          <para>Why do MacOS and Windows 98 connections freeze when
            running PPPoE on the gateway?</para>
        </question>

        <answer>
          <para>Thanks to Michael Wozniak
            <email>mwozniak@netcom.ca</email> for figuring this out and
            Dan Flemming <email>danflemming@mac.com</email> for the Mac
            solution:</para>

          <para>This is due to what is called a <quote>Black Hole</quote>
            router.  MacOS and Windows 98 (and maybe other Microsoft OSs)
            send TCP packets with a requested segment size too big to fit
            into a PPPoE frame (MTU is 1500 by default for Ethernet)
            <emphasis>and</emphasis> have the <quote>do not
            fragment</quote> bit set (default of TCP) and the Telco router
            is not sending ICMP <quote>must fragment</quote> back to the
            www site you are trying to load.  (Alternatively, the router is
            sending the ICMP packet correctly, but the firewall at the www
            site is dropping it.)  When the www server is sending
            you frames that do not fit into the PPPoE pipe the Telco router
            drops them on the floor and your page does not load (some
            pages/graphics do as they are smaller than a MSS.) This seems
            to be the default of most Telco PPPoE configurations (if only
            they knew how to program a router... sigh...)</para>

          <para>One fix is to use regedit on your 95/98 boxes to add the
            following registry entry...</para>

          <programlisting>HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Class\NetTrans\0000\MaxMTU</programlisting>

          <para>It should be a string with a value <quote>1436</quote>, as
            some ADSL routers are reported to be unable to deal with packets
            larger than this.  This registry key has been changed to
            <literal>Tcpip\Parameters\Interfaces\<replaceable>ID for adapter</replaceable>\MTU</literal>
            in Windows 2000 and becomes a DWORD.</para>

          <para>Refer to the Microsoft Knowledge Base documents <ulink
            url="http://support.microsoft.com/support/kb/articles/Q158/4/74.asp">Q158474
            - Windows TCPIP Registry Entries</ulink> and <ulink
            url="http://support.microsoft.com/support/kb/articles/Q120/6/42.asp">Q120642
            - TCPIP & NBT Configuration Parameters for Windows
            NT</ulink> for more information on changing Windows MTU to
            work with a NAT router.</para>

          <para>Another regedit possibility under Windows 2000 is to
            set the
            <literal>Tcpip\Parameters\Interfaces\<replaceable>ID for
            adapter</replaceable>\EnablePMTUBHDetect</literal> DWORD
            to 1 as mentioned in the Microsoft document 120642
            mentioned above.</para>

          <para>Unfortunately, MacOS does not provide an interface for
            changing TCP/IP settings. However, there is commercial software
            available, such as OTAdvancedTuner (OT for OpenTransport, the
            MacOS TCP/IP stack) by <ulink
            URL="http://www.softworks.com/">Sustainable Softworks</ulink>,
            that will allow users to customize TCP/IP settings. MacOS NAT
            users should select <literal>ip_interface_MTU</literal> from
            the drop-down menu, enter <literal>1450</literal> instead of
            <literal>1500</literal> in the box, click the box next to
            <literal>Save as Auto Configure</literal>, and click
            <literal>Make Active</literal>.</para>

          <para>The latest version of &man.ppp.8;
            (2.3 or greater) has an <command>enable tcpmssfixup</command>
            command that will automatically adjust the MSS to an appropriate
            value.  This facility is enabled by default.  If you are stuck
            with an older version of &man.ppp.8;, you
            may want to look at the <application>tcpmssd</application>
            port.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="desperation">
          <para>None of this helps - I am desperate!  What can I do?</para>
        </question>

        <answer>
          <para>If all else fails, send as much information as you can,
            including your config files, how you are starting
            &man.ppp.8;, the relevant parts of your
            log file and the output of the <command>netstat -rn</command>
            command (before and after connecting) to the &a.questions; or
            the <ulink URL="news:comp.unix.bsd.freebsd.misc">
            comp.unix.bsd.freebsd.misc</ulink> news group, and someone
            should point you in the right direction.</para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="serial">
    <title>Serial Communications</title>

    <para>This section answers common questions about serial
      communications with FreeBSD.  PPP and SLIP are covered in the
      <xref linkend="networking" remap="Networking"> section.</para>


    <qandaset>
      <qandaentry>
        <question id="found-serial">
          <para>How do I tell if FreeBSD found my serial ports?</para>
        </question>

        <answer>
          <para>As the FreeBSD kernel boots, it will probe for the serial
            ports in your system for which the kernel was configured.
            You can either watch your system closely for the messages it
            prints or run the command</para>

          <screen>&prompt.user; <userinput>dmesg | grep sio</userinput></screen>

          <para>after your system is up and running.</para>

          <para>Here is some example output from the above command:</para>

          <programlisting>sio0 at 0x3f8-0x3ff irq 4 on isa
sio0: type 16550A
sio1 at 0x2f8-0x2ff irq 3 on isa
sio1: type 16550A</programlisting>

          <para>This shows two serial ports.  The first is on irq 4, is
            using port address <literal>0x3f8</literal>, and has a
            16550A-type UART chip.  The second uses the same kind of chip
            but is on irq 3 and is at port address <literal>0x2f8</literal>.
            Internal modem cards are treated just like serial ports---except
            that they always have a modem <quote>attached</quote> to the
            port.</para>

          <para>The <filename>GENERIC</filename> kernel includes support
            for two serial ports using the same irq and port address
            settings in the above example.  If these settings are not
            right for your system, or if you have added modem cards or have
            more serial ports than your kernel is configured for, just
            reconfigure your kernel.  See section
            <link linkend="make-kernel">about building a kernel</link> for
            more details.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="found-modem">
          <para>How do I tell if FreeBSD found my modem cards?</para>
        </question>

        <answer>
          <para>Refer to the answer to the previous question.</para>

        </answer>
      </qandaentry>

      <qandaentry>
        <question id="missing-tty0X">
          <para>I just upgraded to 2.0.5 and my
            <devicename>tty0<replaceable>X</replaceable></devicename>
            are missing!  How do I solve this problem?</para>
        </question>

        <answer>
          <para>Do not worry, they have been merged with the
            <devicename>ttyd<replaceable>X</replaceable></devicename> devices. You will have to change
            any old configuration files you have, though.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="access-serial-ports">
          <para>How do I access the serial ports on FreeBSD?</para>
        </question>

        <answer>
          <para>The third serial port,
            <devicename>sio2</devicename>
            (see &man.sio.4;, known as COM3 in DOS), is on <devicename>/dev/cuaa2</devicename>
            for dial-out devices, and on <devicename>/dev/ttyd2</devicename>
            for dial-in devices.  What is the difference between these two
            classes of devices?</para>

          <para>You use <devicename>ttyd<replaceable>X</replaceable></devicename> for dial-ins.  When
            opening <devicename>/dev/ttyd<replaceable>X</replaceable></devicename> in blocking mode, a
            process will wait for the corresponding
            <devicename>cuaa<replaceable>X</replaceable></devicename> device to become inactive, and then
            wait for the carrier detect line to go active.  When you open
            the <devicename>cuaa<replaceable>X</replaceable></devicename> device, it makes sure the serial
            port is not already in use by the <devicename>ttyd<replaceable>X</replaceable></devicename>
            device. If the port is available, it <quote>steals</quote> it
            from the <devicename>ttyd<replaceable>X</replaceable></devicename> device. Also, the
            <devicename>cuaa<replaceable>X</replaceable></devicename> device does not care about carrier
            detect. With this scheme and an auto-answer modem, you can have
            remote users log in and you can still dialout with the same
            modem and the system will take care of all the
            conflicts.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="enable-multiport-serial">
          <para>How do I enable support for a multiport serial
            card?</para>
        </question>

        <answer>
          <para>Again, the section on kernel configuration provides
            information about configuring your kernel. For a multiport
            serial card, place an &man.sio.4; line
            for each serial port on the card in the kernel configuration
            file. But place the irq and vector specifiers on only one of
            the entries. All of the ports on the card should share one irq.
            For consistency, use the last serial port to specify the irq.
            Also, specify the <literal>COM_MULTIPORT</literal>
            option.</para>

          <para>The following example is for an AST 4-port serial card on
            irq 7:</para>

          <programlisting>options "COM_MULTIPORT"
device sio4 at isa? port 0x2a0 tty flags 0x781
device sio5 at isa? port 0x2a8 tty flags 0x781
device sio6 at isa? port 0x2b0 tty flags 0x781
device sio7 at isa? port 0x2b8 tty flags 0x781 irq 7 vector siointr</programlisting>

          <para>The flags indicate that the master port has minor number 7
            (<literal>0x700</literal>), diagnostics enabled during probe
            (<literal>0x080</literal>), and all the ports share an irq
            (<literal>0x001</literal>).</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="multiport-serial-share-irq">
          <para>Can FreeBSD handle multiport serial cards sharing
            irqs?</para>
        </question>

        <answer>
          <para>Not yet. You will have to use a different irq for each
            card.</para>

        </answer>
      </qandaentry>

      <qandaentry>
        <question id="default-serial-params">
          <para>Can I set the default serial parameters for a
            port?</para>
        </question>

        <answer>
          <para>The <devicename>ttyd<replaceable>X</replaceable></devicename> (or
            <devicename>cuaa<replaceable>X</replaceable></devicename>) device is the regular device
            you will want to open for your applications.  When a process
            opens the device, it will have a default set of terminal I/O
            settings. You can see these settings with the command</para>

          <screen>&prompt.root; <userinput>stty -a -f /dev/ttyd1</userinput></screen>

          <para>When you change the settings to this device, the settings
            are in effect until the device is closed.  When it is reopened,
            it goes back to the default set.  To make changes to the
            default set, you can open and adjust the settings of the
            <quote>initial state</quote> device. For example, to turn on
            <acronym>CLOCAL</acronym> mode, 8 bits, and
            <acronym>XON/XOFF</acronym> flow control by default for
            ttyd5, do:</para>

          <screen>&prompt.root; <userinput>stty -f /dev/ttyid5 clocal cs8 ixon ixoff</userinput></screen>

          <para>A good place to do this is in
            <filename>/etc/rc.serial</filename>. Now, an application will
            have these settings by default when it opens
            <filename>ttyd5</filename>.  It can still change these settings
            to its liking, though.</para>

          <para>You can also prevent certain settings from being changed
            by an application by making adjustments to the
            <quote>lock state</quote> device.  For example, to lock the
            speed of <devicename>ttyd5</devicename> to 57600 bps, do</para>

          <screen>&prompt.root; <userinput>stty -f /dev/ttyld5 57600</userinput></screen>

          <para>Now, an application that opens <devicename>ttyd5</devicename>
            and tries to change the speed of the port will be stuck with
          57600 bps.</para>

          <para>Naturally, you should make the initial state and lock state
            devices writable only by <username>root</username>. The
            &man.MAKEDEV.8;
            script does <emphasis>NOT</emphasis> do this when it creates the
            device entries.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="enable-dialup">
          <para>How can I enable dialup logins on my modem?</para>
        </question>

        <answer>
          <para>So you want to become an Internet service provider, eh?
            First, you will need one or more modems that can auto-answer.
            Your modem will need to assert carrier-detect when it detects a
            carrier and not assert it all the time. It will need to hang up
            the phone and reset itself when the data terminal ready
            (<acronym>DTR</acronym>) line goes from on to off. It should
            probably use <filename>RTS/CTS</filename> flow control or no
            local flow control at all. Finally, it must use a constant
            speed between the computer and itself, but (to be nice to your
            callers) it should negotiate a speed between itself and the
            remote modem.</para>

          <para>For many Hayes command-set--compatible modems, this
            command will make these settings and store them in
            nonvolatile memory:</para>

          <programlisting>AT &amp;C1 &amp;D3 &amp;K3 &amp;Q6 S0=1 &amp;W</programlisting>

          <para>See the section <link linkend="direct-at">on sending AT
            commands</link> below for information on how to make these
            settings without resorting to an MS-DOS terminal program.</para>

          <para>Next, make an entry in
            <filename>/etc/ttys</filename> (see &man.ttys.5;) for the modem.  This file lists all the ports
            on which the operating system will await logins.  Add a line
            that looks something like this:</para>

          <programlisting>ttyd1 "/usr/libexec/getty std.57600" dialup on insecure</programlisting>

          <para>This line indicates that the second serial port
            (<devicename>/dev/ttyd1</devicename>) has a modem connected
            running at 57600 bps and no parity
            (<literal>std.57600</literal>, which comes from the file
            <filename>/etc/gettytab</filename>, see &man.gettytab.5;).
            The terminal type for this port is <literal>dialup</literal>.
            The port is <literal>on</literal> and is
            <literal>insecure</literal>---meaning root logins on the port
            are not allowed. For dialin ports like this one, use the
            <devicename>ttyd<replaceable>X</replaceable></devicename> entry.</para>

          <para>It is common practice to use <literal>dialup</literal> as
            the terminal type. Many users set up in their <filename>.profile</filename> or
            <filename>.login</filename> files a prompt for the actual terminal type if the
            starting type is dialup. The example shows the port as
            insecure. To become root on this port, you have to login as a
            regular user, then &man.su.1; to become
            <username>root</username>. If you use <literal>secure</literal>
            then <username>root</username> can login in directly.</para>

          <para>After making modifications to
            <filename>/etc/ttys</filename>, you need to send a hangup or
            <acronym>HUP</acronym> signal to the
            &man.init.8; process:</para>

          <screen>&prompt.root; <userinput>kill -HUP 1</userinput></screen>

          <para>This forces the &man.init.8; process to reread
            <filename>/etc/ttys</filename>.  The init process will then start getty
            processes on all <literal>on</literal> ports.  You can find
            out if logins are available for your port by typing</para>

          <screen>&prompt.user; <userinput>ps -ax | grep '[t]tyd1'</userinput></screen>

          <para>You should see something like:</para>

          <programlisting>747 ??  I      0:00.04 /usr/libexec/getty std.57600 ttyd1</programlisting>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="dumb-terminal">
          <para>How can I connect a dumb terminal to my FreeBSD
            box?</para>
        </question>

        <answer>
          <para>If you are using another computer as a terminal into your
            FreeBSD system, get a null modem cable to go between the two
            serial ports.  If you are using an actual terminal, see its
            accompanying instructions.</para>

          <para>Then, modify
            <filename>/etc/ttys</filename> (see &man.ttys.5;), like above.  For example, if you are
            hooking up a WYSE-50 terminal to the fifth serial port,
            use an entry like this:</para>

          <programlisting>ttyd4 "/usr/libexec/getty std.38400" wyse50 on secure</programlisting>

          <para>This example shows that the port on
            <devicename>/dev/ttyd4</devicename> has a wyse50 terminal
            connected at 38400 bps with no parity
            (<literal>std.38400</literal> from
            <filename>/etc/gettytab</filename>, see &man.gettytab.5;) and <username>root</username> logins are
            allowed (<literal>secure</literal>).</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="cannot-tip">
          <para>Why can I not run <command>tip</command> or
            <command>cu</command>?</para>
        </question>

        <answer>
          <para>On your system, the programs &man.tip.1;
            and &man.cu.1;
            are probably executable only by
            <username>uucp</username>
            and group <groupname>dialer</groupname>.  You can use the group
            <groupname>dialer</groupname> to control who has access to your
            modem or remote systems.  Just add yourself to group
            dialer.</para>

          <para>Alternatively, you can let everyone on your system
            run &man.tip.1; and &man.cu.1; by
            typing:</para>

          <screen>&prompt.root; <userinput>chmod 4511 /usr/bin/cu</userinput>
&prompt.root; <userinput>chmod 4511 /usr/bin/tip</userinput></screen>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="hayes-unsupported">
          <para>My stock Hayes modem is not supported---what
            can I do?</para>
        </question>

        <answer>
          <para>Actually, the man page for &man.tip.1; is
            out of date.  There is a generic Hayes dialer already built in.
            Just use <literal>at=hayes</literal> in your
            <filename>/etc/remote</filename> (see &man.remote.5;) file.</para>

          <para>The Hayes driver is not smart enough to recognize some of
            the advanced features of newer modems---messages like
            <literal>BUSY</literal>, <literal>NO DIALTONE</literal>, or
            <literal>CONNECT 115200</literal> will just confuse it. You
            should turn those messages off when you use &man.tip.1;
            (using <literal>ATX0&amp;W</literal>).</para>

          <para>Also, the dial timeout for &man.tip.1; is 60
            seconds.  Your modem should use something less, or else tip
            will think there is a communication problem.  Try
            <literal>ATS7=45&amp;W</literal>.</para>

          <para>Actually, as shipped &man.tip.1; does not yet
            support it fully. The solution is to edit the file
            <filename>tipconf.h</filename> in the directory
            <filename>/usr/src/usr.bin/tip/tip</filename>.  Obviously you
            need the source distribution to do this.</para>

          <para>Edit the line <literal>#define HAYES 0</literal>
            to <literal>#define HAYES 1</literal>. Then
            <command>make</command> and <command>make install</command>.
            Everything works nicely after that.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="direct-at">
          <para>How am I expected to enter these AT commands?</para>
        </question>

        <answer>
          <para>Make what is called a <quote>direct</quote> entry in your
            <filename>/etc/remote</filename> file (see &man.remote.5;).  For example, if your modem is hooked
            up to the first serial port, <devicename>/dev/cuaa0</devicename>,
            then put in the following line:</para>

          <programlisting>cuaa0:dv=/dev/cuaa0:br#19200:pa=none</programlisting>

          <para>Use the highest bps rate your modem supports in the br
            capability.  Then, type
            <command>tip <devicename>cuaa0</devicename></command> (see &man.tip.1;)
            and you will be connected to your modem.</para>

          <para>If there is no <devicename>/dev/cuaa0</devicename> on your
            system, do this:</para>

          <screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>sh MAKEDEV cuaa0</userinput></screen>

          <para>Or use cu as <username>root</username> with the following command:</para>

          <screen>&prompt.root; <userinput>cu -l<replaceable>line</replaceable> -s<replaceable>speed</replaceable></userinput></screen>

          <para>with <replaceable>line</replaceable> being the serial port (e.g.
            <devicename>/dev/cuaa0</devicename>) and <replaceable>speed</replaceable> being the speed
            (e.g.<literal>57600</literal>).  When you are done entering
            the AT commands hit <literal>~.</literal> to exit.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="gt-failure">
          <para>Why does the <literal>&lt;@&gt;</literal> sign for the pn
            capability not work?</para></question><answer>

          <para>The <literal>&lt;@&gt;</literal> sign in the phone number
            capability tells tip to look in
            <filename>/etc/phones</filename> for a phone number.  But the
            <literal>&lt;@&gt;</literal> sign is also a special character
            in capability files like <filename>/etc/remote</filename>.
            Escape it with a backslash:</para>

          <programlisting>pn=\@</programlisting>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="dial-command-line">
          <para>How can I dial a phone number on the command
            line?</para>
        </question><answer>

          <para>Put what is called a <quote>generic</quote> entry in your
            <filename>/etc/remote</filename> file (see &man.remote.5;).  For example:</para>

          <programlisting>tip115200|Dial any phone number at 115200 bps:\
        :dv=/dev/cuaa0:br#115200:at=hayes:pa=none:du:
tip57600|Dial any phone number at 57600 bps:\
        :dv=/dev/cuaa0:br#57600:at=hayes:pa=none:du:</programlisting>

          <para>Then you can do something like <command>tip -115200
            5551234</command>.  If you prefer &man.cu.1;
            over
            &man.tip.1;, use a generic cu entry:</para>

          <programlisting>cu115200|Use cu to dial any number at 115200bps:\
        :dv=/dev/cuaa1:br#57600:at=hayes:pa=none:du:</programlisting>

          <para>and type <command>cu 5551234 -s 115200</command>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="set-bps">
          <para>Do I have to type in the bps rate every time I do
            that?</para>
        </question><answer>

          <para>Put in an entry for <literal>tip1200</literal> or
            <literal>cu1200</literal>, but go ahead and use whatever bps
            rate is appropriate with the br capability.
            &man.tip.1;
            thinks a good default is 1200 bps which is why it looks for
            a <literal>tip1200</literal> entry. You do not have to use 1200
            bps, though.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="terminal-server">
          <para>How can I more easily access a number of hosts through a
            terminal server?</para>
        </question>

        <answer>
          <para>Rather than waiting until you are connected and typing
            <literal>CONNECT <replaceable>host</replaceable></literal>
            each time, use tip's <literal>cm</literal> capability. For
            example, these entries in
            <filename>/etc/remote</filename> (see &man.remote.5;):</para>

          <programlisting>pain|pain.deep13.com|Forrester's machine:\
        :cm=CONNECT pain\n:tc=deep13:
muffin|muffin.deep13.com|Frank's machine:\
        :cm=CONNECT muffin\n:tc=deep13:
deep13:Gizmonics Institute terminal server:\
        :dv=/dev/cuaa2:br#38400:at=hayes:du:pa=none:pn=5551234:</programlisting>

          <para>will let you type <command>tip pain</command> or
            <command>tip muffin</command> to connect to the hosts
            <hostid>pain</hostid> or <hostid>muffin</hostid>; and
            <command>tip deep13</command> to get to the terminal
            server.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="tip-multiline">
          <para>Can tip try more than one line for each site?</para>
        </question>

        <answer>
          <para>This is often a problem where a university has several
            modem lines and several thousand students trying to use
            them...</para>

          <para>Make an entry for your university in
            <filename>/etc/remote</filename> (see &man.remote.5;) and use <literal>&lt;\@&gt;</literal> for
            the <literal>pn</literal> capability:</para>

          <programlisting>big-university:\
        :pn=\@:tc=dialout
dialout:\
        :dv=/dev/cuaa3:br#9600:at=courier:du:pa=none:</programlisting>

          <para>Then, list the phone numbers for the university in
            <filename>/etc/phones</filename> (see &man.phones.5;):</para>

          <programlisting>big-university 5551111
big-university 5551112
big-university 5551113
big-university 5551114</programlisting>

          <para>&man.tip.1;
            will try each one in the listed order, then give
            up.  If you want to keep retrying, run &man.tip.1;
            in a while loop.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="multi-controlp">
          <para>Why do I have to hit CTRL+P twice to send CTRL+P
            once?</para>
        </question>

        <answer>
          <para>CTRL+P is the default <quote>force</quote> character,
            used to tell &man.tip.1;
            that the next character is literal data.  You can set the
            force character to any other character with the
            <literal>~s</literal> escape, which means <quote>set a
            variable</quote>.</para>

          <para>Type <literal>~sforce=<replaceable>single-char
            </replaceable></literal> followed by a newline.
            <replaceable>single-char</replaceable> is any single character.
            If you leave out <replaceable>single-char</replaceable>,
            then the force character is the nul character, which you can
            get by typing CTRL+2 or CTRL+SPACE.  A pretty good value for
            <replaceable>single-char</replaceable> is SHIFT+CTRL+6, which
            I have seen only used on some terminal servers.</para>

          <para>You can have the force character be whatever you want by
            specifying the following in your
            <filename>$HOME/.tiprc</filename> file:</para>

          <programlisting>force=<replaceable>single-char</replaceable></programlisting>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="uppercase">
          <para>Why is everything I type suddenly in UPPER CASE?</para>
        </question>

        <answer>
          <para>You must have pressed CTRL+A, &man.tip.1;
            <quote>raise character</quote>, specially
            designed for people with broken caps-lock keys. Use
            <literal>~s</literal> as above and set the variable
            <quote>raisechar</quote> to something reasonable.  In fact,
            you can set it to the same as the force character, if you
            never expect to use either of these features.</para>

          <para>Here is a sample .tiprc file perfect for Emacs users who
            need to type CTRL+2 and CTRL+A a lot:</para>

          <programlisting>force=^^
raisechar=^^</programlisting>

<para>The ^^ is SHIFT+CTRL+6.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="tip-filetransfer">
          <para>How can I do file transfers with
            <command>tip</command>?</para>
        </question>

        <answer>
          <para>If you are talking to another Unix system, you can send
            and receive files with <literal>~p</literal> (put) and
            <literal>~t</literal> (take).  These commands run
            &man.cat.1; and
            &man.echo.1; on the remote system to accept and send files.
            The syntax is:</para>

          <programlisting>~p &lt;local-file&gt; [&lt;remote-file&gt;]
~t &lt;remote-file&gt; [&lt;local-file&gt;]</programlisting>

          <para>There is no error checking, so you probably should use
            another protocol, like zmodem.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="zmodem-tip">
          <para>How can I run zmodem with
            <application>tip</application>?</para>
        </question>

        <answer>
          <para>First, install one of the zmodem programs from the
            ports collection (such as one of the two from the comms
            category, <application>lrzsz</application> or
            <application>rzsz</application>.</para>

          <para>To receive files, start the sending program on the
            remote end.  Then, press enter and type
            <literal>~C rz</literal> (or <literal>~C lrz</literal> if you
            installed <application>lrzsz</application>) to begin
            receiving them locally.</para>

          <para>To send files, start the receiving program on the remote
            end.  Then, press enter and type
            <literal>~C sz <replaceable>files</replaceable></literal>
            (or <literal>~C lsz <replaceable>files</replaceable></literal>)
            to send them to the remote system.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="cannot-find-serial">
          <para>Why does FreeBSD not find my serial ports, even
            when the settings are correct?</para>
        </question>

        <answer>
          <para>Motherboards and cards with Acer UARTs do not probe
            properly under the FreeBSD sio probe.  Obtain a patch from
            <ulink URL="http://www.lemis.com/serial-port-patch.html">
            www.lemis.com</ulink> to fix your problem.</para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="misc">
    <title>Miscellaneous Questions</title>

    <qandaset>
      <qandaentry>
        <question id="more-swap">
          <para>FreeBSD uses far more swap space than Linux. Why?</para>
        </question>

        <answer>
          <para>FreeBSD only appears to use more swap than Linux.  In
            actual fact, it does not. The main difference between FreeBSD
            and Linux in this regard is that FreeBSD will proactively move
            entirely idle, unused pages of main memory into swap in order
            to make more main memory available for active use. Linux tends
            to only move pages to swap as a last resort. The perceived
            heavier use of swap is balanced by the more efficient use of
            main memory.</para>

          <para>Note that while FreeBSD is proactive in this regard, it
            does not arbitrarily decide to swap pages when the system is
            truly idle.  Thus you will not find your system all paged
            out when you get up in the morning after leaving it idle
            overnight.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="top-freemem">
          <para>Why does <command>top</command> show very little free memory even
            when I have very few programs running?</para>
        </question>

        <answer>
          <para>The simple answer is that free memory is wasted
            memory.  Any memory that your programs do not actively
            allocate is used within the FreeBSD kernel as disk
            cache.  The values shown by &man.top.1; labeled as
            <literal>Inact</literal>, <literal>Cache</literal>, and
            <literal>Buf</literal> are all cached data at different
            aging levels.  This cached data means the system does
            not have to access a slow disk again for data it has
            accessed recently, thus increasing overall performance.
            In general, a low value shown for <literal>Free</literal>
            memory in &man.top.1; is good, provided it is not
            <emphasis>very</emphasis> low.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="aout-elf">
          <para>Why use (what are) a.out and ELF executable
            formats?</para>
        </question>

        <answer>
          <para>To understand why FreeBSD uses the
            <filename>ELF</filename> format, you must first know a little
            about the 3 currently <quote>dominant</quote> executable
            formats for Unix:</para>

            <note>
              <para>Prior to FreeBSD 3.x, FreeBSD used the a.out
                format.</para>
            </note>

            <itemizedlist>
              <listitem>
                <para>&man.a.out.5;</para>

                <para>The oldest and <quote>classic</quote> Unix object
                  format.  It uses a short and compact header with a magic
                  number at the beginning that is often used to
                  characterize the format (see
                  &man.a.out.5; for more details).  It contains three
                  loaded segments: .text, .data, and .bss plus a symbol
                  table and a string table.</para>
              </listitem>

              <listitem>
                <para><acronym>COFF</acronym></para>

                <para>The SVR3 object format.  The header now comprises
                  a section table, so you can have more than just .text,
                  .data, and .bss sections.</para>
              </listitem>

              <listitem>
                <para><acronym>ELF</acronym></para>

                <para>The successor to <acronym>COFF</acronym>, featuring
                  Multiple sections and 32-bit or 64-bit possible values.
                  One major drawback: <acronym>ELF</acronym> was also
                  designed with the assumption that there would be only
                  one ABI per system architecture.  That assumption is
                  actually quite incorrect, and not even in the
                  commercial SYSV world (which has at least three ABIs:
                  SVR4, Solaris, SCO) does it hold true.</para>

                <para>FreeBSD tries to work around this problem somewhat
                  by providing a utility for <emphasis>branding</emphasis>
                  a known <acronym>ELF</acronym> executable with
                  information about the ABI it is compliant with.  See the
                  man page for &man.brandelf.1;
                  for more information.</para>
              </listitem>
            </itemizedlist>

          <para>FreeBSD comes from the <quote>classic</quote> camp and has
            traditionally used the &man.a.out.5;
            format, a technology tried and proven through
            many generations of BSD releases. Though it has also been
            possible for some time to build and run native
            <acronym>ELF</acronym> binaries (and kernels) on a FreeBSD
            system, FreeBSD initially resisted the <quote>push</quote> to
            switch to <acronym>ELF</acronym> as the default format. Why?
            Well, when the Linux camp made their painful transition to
            <acronym>ELF</acronym>, it was not so much to flee the
            <filename>a.out</filename> executable format as it was their
            inflexible jump-table based shared library mechanism, which
            made the construction of shared libraries very difficult for
            vendors and developers alike. Since the <acronym>ELF</acronym>
            tools available offered a solution to the shared library
            problem and were generally seen as <quote>the way
            forward</quote> anyway, the migration cost was accepted as
            necessary and the transition made.</para>

          <para>In FreeBSD's case, our shared library mechanism is based
            more closely on Sun's <application>SunOS</application>-style
            shared library mechanism and, as such, is very easy to use.
            However, starting with 3.0, FreeBSD officially supports
            <acronym>ELF</acronym> binaries as the default format. Even
            though the <filename>a.out</filename> executable format has
            served us well, the GNU people, who author the compiler tools
            we use, have dropped support for the <filename>a.out</filename>
            format. This has forced us to maintain a divergent version of
            the compiler and linker, and has kept us from reaping the
            benefits of the latest GNU development efforts. Also the
            demands of ISO-C++, notably constructors and destructors, has
            also led to native <acronym>ELF</acronym> support in future
            FreeBSD releases.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="binary-formats">
          <para>Yes, but why are there so many different formats?</para>
        </question>

        <answer>
          <para>Back in the dim, dark past, there was simple hardware.
            This simple hardware supported a simple, small system. a.out
            was completely adequate for the job of representing binaries on
            this simple system (a PDP-11). As people ported Unix from this
            simple system, they retained the a.out format because it was
            sufficient for the early ports of Unix to architectures like
            the Motorola 68k, VAXen, etc.</para>

          <para>Then some bright hardware engineer decided that if he
            could force software to do some sleazy tricks, then he would be
            able to shave a few gates off the design and allow his CPU core
            to run faster. While it was made to work with this new kind of
            hardware (known these days as RISC), <filename>a.out</filename>
            was ill-suited for this hardware, so many formats were
            developed to get to a better performance from this hardware
            than the limited, simple <filename>a.out</filename> format
            could offer. Things like <acronym>COFF</acronym>,
            <acronym>ECOFF</acronym>, and a few obscure others were
            invented and their limitations explored before things seemed to
            settle on <acronym>ELF</acronym>.</para>

          <para>In addition, program sizes were getting huge and disks
            (and physical memory) were still relatively small so the
            concept of a shared library was born. The VM system also became
            more sophisticated. While each one of these advancements was
            done using the <filename>a.out</filename> format, its
            usefulness was stretched more and more with each new feature.
            In addition, people wanted to dynamically load things at run
            time, or to junk parts of their program after the init code had
            run to save in core memory and/or swap space. Languages became
            more sophisticated and people wanted code called before main
            automatically. Lots of hacks were done to the
            <filename>a.out</filename> format to allow all of these things
            to happen, and they basically worked for a time. In time,
            <filename>a.out</filename> was not up to handling all these
            problems without an ever increasing overhead in code and
            complexity. While <acronym>ELF</acronym> solved many of these
            problems, it would be painful to switch from the system that
            basically worked. So <acronym>ELF</acronym> had to wait until
            it was more painful to remain with <filename>a.out</filename>
            than it was to migrate to <acronym>ELF</acronym>.</para>

          <para>However, as time passed, the build tools that FreeBSD
            derived their build tools from (the assembler and loader
            especially) evolved in two parallel trees. The FreeBSD tree
            added shared libraries and fixed some bugs. The GNU folks that
            originally write these programs rewrote them and added simpler
            support for building cross compilers, plugging in different
            formats at will, etc. Since many people wanted to build cross
            compilers targeting FreeBSD, they were out of luck since the
            older sources that FreeBSD had for as and ld were not up to the
            task. The new gnu tools chain (binutils) does support cross
            compiling, <acronym>ELF</acronym>, shared libraries, C++
            extensions, etc. In addition, many vendors are releasing
            <acronym>ELF</acronym> binaries, and it is a good thing for
            FreeBSD to run them. And if it is running
            <acronym>ELF</acronym> binaries, why bother having
            <filename>a.out</filename> any more? It is a tired old horse
            that has proven useful for a long time, but it is time to turn
            him out to pasture for his long, faithful years of
            service.</para>

          <para><acronym>ELF</acronym> is more expressive than a.out and
            will allow more extensibility in the base system. The
            <acronym>ELF</acronym> tools are better maintained, and offer
            cross compilation support, which is important to many people.
            <acronym>ELF</acronym> may be a little slower than a.out, but
            trying to measure it can be difficult. There are also numerous
            details that are different between the two in how they map
            pages, handle init code, etc. None of these are very important,
            but they are differences. In time support for
            <filename>a.out</filename> will be moved out of the GENERIC
            kernel, and eventually removed from the kernel once the need to
            run legacy <filename>a.out</filename> programs is past.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="chmod-symlinks">
          <para>Why will chmod not change the permissions on symlinks?</para>
        </question>

        <answer>
          <para>Symlinks do not have permissions, and by default,
            &man.chmod.1; will not follow symlinks to change the
            permissions on the target file. So if you have a file,
            <filename>foo</filename>, and a symlink to that file,
            <filename>bar</filename>, then this command will always
            succeed.</para>

          <screen>&prompt.user; <userinput>chmod g-w bar</userinput></screen>

          <para>However, the permissions on <filename>foo</filename> will
            not have changed.</para>

          <para>You have to use either <option>-H</option> or
            <option>-L</option> together with the <option>-R</option>
            option to make this work.  See the
            &man.chmod.1; and &man.symlink.7;
            man pages for more info.</para>

            <warning>
              <para>The <option>-R</option> option does a
                <acronym>RECURSIVE</acronym>
                &man.chmod.1;.  Be careful about
                specifying directories or symlinks to directories to
                &man.chmod.1;.  If you want to
                change the permissions of a directory referenced by a
                symlink, use &man.chmod.1;
                without any options and follow the symlink
                with a trailing slash (<filename>/</filename>).  For
                example, if <filename>foo</filename> is a symlink to
                directory <filename>bar</filename>, and you want to change
                the permissions of <filename>foo</filename> (actually
                <filename>bar</filename>), you would do something
                like:</para>

              <screen>&prompt.user; <userinput>chmod 555 foo/</userinput></screen>

              <para>With the trailing slash, &man.chmod.1;
                will follow the symlink,
                <filename>foo</filename>, to change the permissions of the
                directory, <filename>bar</filename>.</para>
            </warning>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="login-8char">
          <para>Why are login names restricted to 8 characters or less
            in FreeBSD 2.2.X and earlier?</para>
        </question>

        <answer>

          <para>You would think it would be easy enough to change
            <literal>UT_NAMESIZE</literal> and rebuild the whole world,
            and everything would just work. Unfortunately there are often
            scads of applications and utilities (including system tools)
            that have hard-coded small numbers (not always
            <literal>8</literal> or <literal>9</literal>, but oddball ones
            like <literal>15</literal> and <literal>20</literal>) in
            structures and buffers. Not only will this get you log files
            which are trashed (due to variable-length records getting
            written when fixed records were expected), but it can break
            Suns NIS clients and potentially cause other problems in
            interacting with other Unix systems.</para>

          <para>In FreeBSD 3.0 and later, the maximum name length has
            been increased to 16 characters and those various utilities
            with hard-coded name sizes have been found and fixed. The fact
            that this touched so many areas of the system is why, in fact,
            the change was not made until 3.0.</para>

          <para>If you are absolutely confident in your ability to find
            and fix these sorts of problems for yourself when and if they
            pop up, you can increase the login name length in earlier
            releases by editing <filename>/usr/include/utmp.h</filename> and changing
            UT_NAMESIZE accordingly. You must also update MAXLOGNAME in
            <filename>/usr/include/sys/param.h</filename> to match the UT_NAMESIZE change.
            Finally, if you build from sources, do not forget that
            /usr/include is updated each time! Change the appropriate files
            in /usr/src/.. instead.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="dos-binaries">
          <para>Can I run DOS binaries under FreeBSD?</para>
        </question>

        <answer>
          <para>Yes, starting with version 3.0 you can using BSDI's
            <application>doscmd</application> DOS emulation which has
            been integrated and enhanced. Send mail to the &a.emulation;
            if you are interested in joining this ongoing effort!</para>

          <para>For pre-3.0 systems, there is a neat utility called
            <application>pcemu</application> in the ports collection which emulates an 8088
            and enough BIOS services to run DOS text mode applications.
            It requires the X Window System (provided as XFree86).</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="translation">
          <para>What do I need to do to translate a FreeBSD document into
            my native language?</para>
        </question>

        <answer>
          <para>See the <ulink url="../fdp-primer/translations.html">
            Translation FAQ</ulink> in the FreeBSD Documentation Project
            Primer.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="freebsd-mail-bounces">
	  <para>Why does my email to any address at FreeBSD.org bounce?</para>
        </question>

        <answer>
	  <para>The FreeBSD.org mail system rejects mail that is
            either misconfigured or is potential spam.  Your mail
            might bounce for one of the following reasons:</para>

	  <itemizedlist>
	    <listitem>
              <para>The email is being sent from a known spam
                domain or IP block.</para>

              <para>The FreeBSD mail servers reject email from known
                spam sources.  If you have service through a company
                or domain who generates or relays spam, please switch
                to a service provider who does not.</para>
            </listitem>

            <listitem>
              <para>The body of the email only contains HTML.</para>

              <para>Mail should be sent in plain text only.  Please
                configure your mail user agent to send plain
                text.</para>
            </listitem>

            <listitem>
              <para>The mailer at FreeBSD.org cannot resolve the IP
                address of the connecting host back to a symbolic
                name.</para>

              <para>Working reverse DNS is a standard requirement for
                accepting mail from a host. Set up reverse DNS for
                your mail server's IP address.  Many home services
                (DSL, cable, dialup, etc.) will not give you this
                option.  In this case, relay your email through your
                service provider's mail server.</para>
            </listitem>
          </itemizedlist>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="free-account">
          <para>Where can I find a free FreeBSD account?</para>
        </question>

        <answer>
          <para>While FreeBSD does not provide open access to any of their
            servers, others do provide open access Unix systems.  The
            charge varies and limited services may be available.</para>

          <para><ulink URL="http://www.arbornet.org/">Arbornet,
            Inc</ulink>, also known as M-Net, has been providing open
            access to Unix systems since 1983.  Starting on an Altos
            running System III, the site switched to BSD/OS in 1991.  In
            June of 2000, the site switched again to FreeBSD.  M-Net can be
            accessed via telnet and SSH and provides basic access to the
            entire FreeBSD software suite.  However, network access is
            limited to members and patrons who donate to the system, which
            is run as a non-profit organization.  M-Net also provides an
            bulletin board system and interactive chat.</para>

          <para><ulink URL="http://www.grex.org/">Grex</ulink> provides a
            site very similar to M-Net including the same bulletin board
            and interactive chat software.  However, the machine is a Sun
            4M and is running SunOS</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="sup-define">
          <para>What is <command>sup</command>, and how do I use
            it?</para>
        </question>

        <answer>
          <para><ulink URL="http://www.FreeBSD.org/cgi/ports.cgi?^sup">
            SUP</ulink> stands for Software Update Protocol, and was
            developed by CMU for keeping their development trees in sync.
            We used it to keep remote sites in sync with our central
            development sources.</para>

          <para>SUP is not bandwidth friendly, and has been retired.
            The current recommended method to keep your sources up to
            date is <ulink URL="../handbook/synching.html#CVSUP">
            CVSup</ulink></para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="daemon-name">
          <para>What is the cute little red guy's name?</para>
        </question>

        <answer>
          <para>He does not have one, and is just called <quote>the BSD
            daemon</quote>.  If you insist upon using a name, call him
            <quote>beastie</quote>.  Note that <quote>beastie</quote>
            is pronounced <quote>BSD</quote>.</para>

          <para>You can learn more about the BSD daemon on his <ulink
            url="http://www.mckusick.com/beastie/index.html">home
            page</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="use-beastie">
          <para>Can I use the BSD daemon image?</para>
        </question>

        <answer>
          <para>Perhaps.  The BSD daemon is copyrighted by Marshall
            Kirk McKusick.  You will want to check his <ulink
            url="http://www.mckusick.com/beastie/mainpage/copyright.html">Statement
            on the Use of the BSD Daemon Figure</ulink> for detailed
            usage terms.</para>

          <para>In summary, you are free to use the image in a tasteful
            manner, for personal use, so long as appropriate credit is
            given.  If you want to use him commercially, you must
            contact Kirk McKusick.  More details are available on the
            <ulink
            url="http://www.mckusick.com/beastie/index.html">BSD
            Daemon's home page</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="daemon-images">
          <para>Do you have any BSD daemon images I could use?</para>
        </question>

        <answer>
          <para>You will find eps and Xfig drawings under
            <filename>/usr/share/examples/BSD_daemon/</filename>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="define-MFC">
          <para>What does <acronym>MFC</acronym> mean?</para>
        </question>

        <answer>
          <para>MFC is an acronym for <quote>Merged From -CURRENT</quote>.
            It is used in the CVS logs to denote when a change was
            migrated from the CURRENT to the STABLE branches.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="define-BSD">
          <para>What does <acronym>BSD</acronym> mean?</para>
        </question>

        <answer>
          <para>It stands for something in a secret language that only
            members can know. It does not translate literally but its ok
            to tell you that BSD's translation is something between,
            <quote>Formula-1 Racing Team</quote>, <quote>Penguins are
            tasty snacks</quote>, and <quote>We have a better sense of
            humor than Linux</quote>. :-)</para>

          <para>Seriously, BSD is an acronym for <quote>Berkeley
            Software Distribution</quote>, which is the name the
            Berkeley <acronym>CSRG</acronym> (Computer Systems Research
            Group) chose for their Unix distribution way back when.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="define-repocopy">
          <para>What is a repo-copy?</para>
        </question>

        <answer>
          <para>A repo-copy (which is a short form of <quote>repository
            copy</quote>) refers to the direct copying of files within
            the CVS repository.</para>

          <para>Without a repo-copy, if a file needed to be copied or
            moved to another place in the repository, the committer would
            run <command>cvs add</command> to put the file in its new
            location, and then <command>cvs rm</command> on the old file
            if the old copy was being removed.</para>

          <para>The disadvantage of this method is that the history
            (i.e. the entries in the CVS logs) of the file would not be
            copied to the new location. As the FreeBSD Project considers
            this history very useful, a repository copy is often used
            instead. This is a process where one of the repository meisters
            will copy the files directly within the repository, rather than
            using the &man.cvs.1; program.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="bikeshed-painting">
          <para>Why should I care what color the bikeshed is?</para>
        </question>

        <answer>
          <para>The really, really short answer is that you should not.
            The somewhat longer answer is that just because you are
            capable of building a bikeshed does not mean you should stop
            others from building one just because you do not like the
            color they plan to paint it.  This is a metaphor indicating
            that you need not argue about every little feature just
            because you know enough to do so.  Some people have
            commented that the amount of noise generated by a change is
            inversely proportional to the complexity of the
            change.</para>

          <para>The longer and more complete answer is that after a very
            long argument about whether &man.sleep.1; should take
            fractional second arguments, &a.phk; posted a long
            message entitled <quote><ulink
            url="http://www.FreeBSD.org/cgi/getmsg.cgi?fetch=506636+517178+/usr/local/www/db/text/1999/freebsd-hackers/19991003.freebsd-hackers">A bike
            shed (any colour will do) on greener grass...</ulink></quote>.
            The appropriate portions of that message are quoted
            below.</para>

          <blockquote>
            <attribution>&a.phk; on freebsd-hackers, October
              2, 1999</attribution>

            <para>
              <quote>What is it about this bike shed?</quote> Some
              of you have asked me.</para>

            <para>It is a long story, or rather it is an old story, but
              it is quite short actually.  C. Northcote Parkinson wrote
              a book in the early 1960'ies, called <quote>Parkinson's
              Law</quote>, which contains a lot of insight into the
              dynamics of management.</para>

            <para>[snip a bit of commentary on the book]</para>

            <para>In the specific example involving the bike shed, the
              other vital component is an atomic power-plant, I guess
              that illustrates the age of the book.</para>

            <para>Parkinson shows how you can go in to the board of
              directors and get approval for building a multi-million or
              even billion dollar atomic power plant, but if you want to
              build a bike shed you will be tangled up in endless
              discussions.</para>

            <para>Parkinson explains that this is because an atomic
              plant is so vast, so expensive and so complicated that
              people cannot grasp it, and rather than try, they fall
              back on the assumption that somebody else checked all the
              details before it got this far.  Richard P. Feynmann
              gives a couple of interesting, and very much to the point,
              examples relating to Los Alamos in his books.</para>

            <para>A bike shed on the other hand.  Anyone can build one
              of those over a weekend, and still have time to watch the
              game on TV.  So no matter how well prepared, no matter how
              reasonable you are with your proposal, somebody will seize
              the chance to show that he is doing his job, that he is
              paying attention, that he is
              <emphasis>here</emphasis>.</para>

            <para>In Denmark we call it <quote>setting your
              fingerprint</quote>.  It is about personal pride and
              prestige, it is about being able to point somewhere and
              say <quote>There!  <emphasis>I</emphasis> did that.</quote>
              It is a strong trait in politicians, but present in most
              people given the chance.  Just think about footsteps in
              wet cement.</para>
          </blockquote>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="funnies">
    <title>The FreeBSD Funnies</title>

    <qandaset>
      <qandaentry>
        <question id="very-very-cool">
          <para>How cool is FreeBSD?</para>
        </question>

        <answer>
          <para>Q. Has anyone done any temperature testing while
            running FreeBSD? I know Linux runs cooler than DOS, but have
            never seen a mention of FreeBSD. It seems to run really
            hot.</para>

          <para>A. No, but we have done numerous taste tests on
            blindfolded volunteers who have also had 250 micrograms of
            LSD-25 administered beforehand. 35% of the volunteers said that
            FreeBSD tasted sort of orange, whereas Linux tasted like purple
            haze. Neither group mentioned any significant variances in
	    temperature.  We eventually had to throw the
            results of this survey out entirely anyway when we found that
            too many volunteers were wandering out of the room during the
            tests, thus skewing the results.  We think most of the volunteers
            are at Apple now, working on their new <quote>scratch and
            sniff</quote> GUI. It is a funny old business we are in!</para>

          <para>Seriously, both FreeBSD and Linux use the
            <acronym>HLT</acronym> (halt) instruction when the system is
            idle thus lowering its energy consumption and therefore the
            heat it generates. Also if you have APM (advanced power
            management) configured, then FreeBSD can also put the CPU into
            a low power mode.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="letmeoutofhere">
          <para>Who is scratching in my memory banks??</para>
        </question>

        <answer>
          <para>Q. Is there anything <quote>odd</quote> that FreeBSD
            does when compiling the kernel which would cause the memory to
            make a scratchy sound? When compiling (and for a brief moment
            after recognizing the floppy drive upon startup, as well), a
            strange scratchy sound emanates from what appears to be the
            memory banks.</para>

          <para>A. Yes!  You will see frequent references to
            <quote>daemons</quote> in the BSD documentation, and what most
            people do not know is that this refers to genuine, non-corporeal
            entities that now possess your computer. The scratchy sound
            coming from your memory is actually high-pitched whispering
            exchanged among the daemons as they best decide how to deal
            with various system administration tasks.</para>

          <para>If the noise gets to you, a good
            <command>fdisk /mbr</command> from DOS will get rid of them,
            but do not be surprised if they react adversely and try to stop
            you. In fact, if at any point during the exercise you hear the
            satanic voice of Bill Gates coming from the built-in speaker,
            take off running and do not ever look back! Freed from the
            counterbalancing influence of the BSD daemons, the twin demons
            of DOS and Windows are often able to re-assert total control
            over your machine to the eternal damnation of your soul.
	    Now that you know, given a choice you would probably prefer to get
	    used to the scratchy noises, no?</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="changing-lightbulbs">
          <para>How many FreeBSD hackers does it take to change a
            lightbulb?</para>
        </question>

        <answer>
          <para>One thousand, one hundred and seventy-two:</para>

          <para>Twenty-three to complain to -CURRENT about the lights
            being out;</para>

          <para>Four to claim that it is a configuration problem, and
            that such matters really belong on -questions;</para>

          <para>Three to submit PRs about it, one of which is misfiled
            under doc and consists only of "it's dark";</para>

          <para>One to commit an untested lightbulb which breaks
            buildworld, then back it out five minutes later;</para>

          <para>Eight to flame the PR originators for not including
            patches in their PRs;</para>

          <para>Five to complain about buildworld being broken;</para>

          <para>Thirty-one to answer that it works for them, and they
            must have cvsupped at a bad time;</para>

          <para>One to post a patch for a new lightbulb to -hackers;</para>

          <para>One to complain that he had patches for this three years
            ago, but when he sent them to -CURRENT they were just ignored,
            and he has had bad experiences with the PR system; besides,
            the proposed new lightbulb is non-reflexive;</para>

          <para>Thirty-seven to scream that lightbulbs do not belong in
            the base system, that committers have no right to do things
            like this without consulting the Community, and WHAT IS
            -CORE DOING ABOUT IT!?</para>

          <para>Two hundred to complain about the color of the bicycle
            shed;</para>

          <para>Three to point out that the patch breaks &man.style.9;;</para>

          <para>Seventeen to complain that the proposed new lightbulb is
            under GPL;</para>

          <para>Five hundred and eighty-six to engage in a flame war
            about the comparative advantages of the GPL, the BSD
            license, the MIT license, the NPL, and the personal hygiene
            of unnamed FSF founders;</para>

          <para>Seven to move various portions of the thread to -chat
            and -advocacy;</para>

          <para>One to commit the suggested lightbulb, even though it
            shines dimmer than the old one;</para>

          <para>Two to back it out with a furious flame of a commit
            message, arguing that FreeBSD is better off in the dark than
            with a dim lightbulb;</para>

          <para>Forty-six to argue vociferously about the backing out
            of the dim lightbulb and demanding a statement from
            -core;</para>

          <para>Eleven to request a smaller lightbulb so it will fit
            their Tamagotchi if we ever decide to port FreeBSD to that
            platform;</para>

          <para>Seventy-three to complain about the SNR on -hackers and
            -chat and unsubscribe in protest;</para>

          <para>Thirteen to post "unsubscribe", "How do I unsubscribe?",
            or "Please remove me from the list", followed by the usual
            footer;</para>

          <para>One to commit a working lightbulb while everybody is too
            busy flaming everybody else to notice;</para>

          <para>Thirty-one to point out that the new lightbulb would shine
            0.364% brighter if compiled with TenDRA (although it will have
            to be reshaped into a cube), and that FreeBSD should therefore
            switch to TenDRA instead of EGCS;</para>

          <para>One to complain that the new lightbulb lacks
            fairings;</para>

          <para>Nine (including the PR originators) to ask
            "what is MFC?";</para>

          <para>Fifty-seven to complain about the lights being out two
            weeks after the bulb has been changed.</para>

          <para><emphasis>&a.nik; adds:</emphasis></para>

          <para><emphasis>I was laughing quite hard at
            this.</emphasis></para>

          <para><emphasis>And then I thought,
            "Hang on, shouldn't there be '1 to document it.' in that list somewhere?"</emphasis></para>

          <para><emphasis>And then I was enlightened :-)</emphasis></para>
        </answer>
      </qandaentry>
      
      <qandaentry>
        <question id="dev-null">
          <para>Where does data written to <filename>/dev/null</filename>
	    go?</para>
        </question>
        <answer>
          <para>It goes into a special data sink in the CPU where it
            is converted to heat which is vented through the heatsink
            / fan assembly.  This is why CPU cooling is increasingly
            important; as people get used to faster processors, they
            become careless with their data and more and more of it
            ends up in <filename>/dev/null</filename>, overheating
            their CPUs.  If you delete <filename>/dev/null</filename>
            (which effectively disables the CPU data sink) your CPU
            may run cooler but your system will quickly become
            constipated with all that excess data and start to behave
            erratically.  If you have a fast network connection you
            can cool down your CPU by reading data out of
            <filename>/dev/random</filename> and sending it off
            somewhere; however you run the risk of overheating your
            network connection and <filename>/</filename> or angering
            your ISP, as most of the data will end up getting
            converted to heat by their equipment, but they generally
            have good cooling, so if you do not overdo it you should be
            OK.</para>

	  <para><emphasis>Paul Robinson adds:</emphasis></para>

	  <para>There are other methods. As every good sysadmin knows,
            it is part of standard practise to send data to the screen
            of interesting variety to keep all the pixies that make up
            your picture happy. Screen pixies (commonly mis-typed or
            re-named as 'pixels') are categorised by the type of hat
            they wear (red, green or blue) and will hide or appear
            (thereby showing the colour of their hat) whenever they
            receive a little piece of food. Video cards turn data into
            pixie-food, and then send them to the pixies - the more
            expensive the card, the better the food, so the better
            behaved the pixies are. They also need constant simulation
            - this is why screen savers exist.</para>

          <para>To take your suggestions further, you could just throw
            the random data to console, thereby letting the pixies
            consume it. This causes no heat to be produced at all,
            keeps the pixies happy and gets rid of your data quite
            quickly, even if it does make things look a bit messy on
            your screen.</para>

          <para>Incidentally, as an ex-admin of a large ISP who
            experienced many problems attempting to maintain a stable
            temperature in a server room, I would strongly discourage
            people sending the data they do not want out to the
            network. The fairies who do the packet switching and
            routing get annoyed by it as well.</para>
	</answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="advanced">
    <title>Advanced Topics</title>

    <qandaset>
      <qandaentry>
        <question id="learn-advanced">
          <para>How can I learn more about FreeBSD's internals?</para>
        </question>

        <answer>
          <para>At this time, there is no book on FreeBSD-specific OS
            internals.  Much general UNIX knowledge is directly
            applicable to FreeBSD, however.  Additionally, there are
            BSD-specific books that are still relevant.</para>

          <para>For a list, please check the Handbook's <ulink
            URL="../handbook/bibliography-osinternals.html">Operating
            System Internals Bibliography</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="define-snap-release">
          <para>What are SNAPs and RELEASEs?</para>
        </question>

        <answer>
          <para>There are currently three active/semi-active branches
            in the FreeBSD <ulink
            URL="http://www.FreeBSD.org/cgi/cvsweb.cgi">
            CVS Repository</ulink> (the RELENG_2 branch is probably
            only changed twice a year, which is why there are only three
            active branches of development):</para>

            <itemizedlist>
              <listitem>
                <para><literal>RELENG_2_2</literal>   AKA
                  <emphasis>2.2-STABLE</emphasis></para>
              </listitem>

              <listitem>
                <para><literal>RELENG_3</literal>     AKA
                  <emphasis>3.X-STABLE</emphasis></para>
              </listitem>

              <listitem>
                <para><literal>RELENG_4</literal>      AKA
                  <emphasis>4-STABLE</emphasis></para>
              </listitem>

              <listitem>
                <para><literal>HEAD</literal>         AKA
                  <emphasis>-CURRENT</emphasis>  AKA
                  <emphasis>5.0-CURRENT</emphasis></para>
              </listitem>

            </itemizedlist>

          <para><literal>HEAD</literal> is not an actual branch tag,
            like the other two; it is simply a symbolic constant for
            <quote><emphasis>the current, non-branched development
            stream</emphasis></quote> which we simply refer to as
            <quote>-CURRENT</quote>.</para>

          <para>Right now, <quote>-CURRENT</quote> is the 5.0 development
            stream and the <literal>4-STABLE</literal> branch,
            <symbol>RELENG_4</symbol>, forked off from
            <quote>-CURRENT</quote> in Mar 2000.</para>

          <para>The <literal>2.2-STABLE</literal> branch,
            <symbol>RELENG_2_2</symbol>, departed -CURRENT in November
            1996, and has pretty much been retired.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="custrel">
          <para>How do I make my own custom release?</para>
        </question>

        <answer>
          <para>Please see the <ulink
            url="../../articles/releng/article.html">
            Release Engineering</ulink> article.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="makeworld-clobbers">
          <para>Why does <command>make world</command> clobber my existing
            installed binaries?</para>
        </question>

        <answer>
          <para>Yes, this is the general idea; as its name might suggest,
            <command>make world</command> rebuilds every system binary from
            scratch, so you can be certain of having a clean and consistent
            environment at the end (which is why it takes so long).</para>

          <para>If the environment variable <literal>DESTDIR</literal>
            is defined while running <command>make world</command> or
            <command>make install</command>, the newly-created binaries
            will be deposited in a directory tree identical to the
            installed one, rooted at <literal>${DESTDIR}</literal>.
            Some random combination of shared libraries modifications and
            program rebuilds can cause this to fail in <command>make
            world</command> however.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="bus-speed-defaulted">
          <para>Why does my system say <quote>(bus speed
            defaulted)</quote> when it boots?</para>
        </question>

        <answer>

          <para>The Adaptec 1542 SCSI host adapters allow the user to
            configure their bus access speed in software. Previous versions
            of the 1542 driver tried to determine the fastest usable speed
            and set the adapter to that. We found that this breaks some
            users' systems, so you now have to define the
            <symbol>TUNE_1542</symbol> kernel configuration option in order
            to have this take place. Using it on those systems where it
            works may make your disks run faster, but on those systems
            where it does not, your data could be corrupted.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="ctm">
          <para>Can I follow current with limited Internet access?</para>
        </question>

        <answer>
          <para>Yes, you can do this <literal>without</literal>
            downloading the whole source tree by using the <ulink
            URL="../handbook/synching.html#CTM">CTM facility</ulink>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="split-240k">
          <para>How did you split the distribution into 240k files?</para>
        </question>

        <answer>
          <para>Newer BSD based systems have a <option>-b</option>
            option to split that allows them to split files on arbitrary
            byte boundaries.</para>

          <para>Here is an example from
            <filename>/usr/src/Makefile</filename>.</para>

          <programlisting>bin-tarball:
(cd ${DISTDIR}; \
tar cf - . \
gzip --no-name -9 -c | \
split -b 240640 - \
${RELEASEDIR}/tarballs/bindist/bin_tgz.)</programlisting>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="submitting-kernel-extensions">
          <para>I have written a kernel extension, who do I send it
            to?</para>
        </question>

        <answer>
          <para>Please take a look at <ulink
            URL="../../articles/contributing/index.html">The contributing to FreeBSD article on how to
            submit code</ulink>.</para>

          <para>And thanks for the thought!</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="pnp-initialize">
          <para>How are Plug N Play ISA cards detected and
            initialized?</para>
        </question>

        <answer>
          <para>By: Frank Durda IV
            <email>uhclem@nemesis.lonestar.org</email></para>

          <para>In a nutshell, there a few I/O ports that all of the
            PnP boards respond to when the host asks if anyone is out
            there. So when the PnP probe routine starts, he asks if there
            are any PnP boards present, and all the PnP boards respond with
            their model # to a I/O read of the same port, so the probe
            routine gets a wired-OR <quote>yes</quote> to that question. At
            least one bit will be on in that reply. Then the probe code is
            able to cause boards with board model IDs (assigned by
            Microsoft/Intel) lower than X to go <quote>off-line</quote>. It
            then looks to see if any boards are still responding to the
            query. If the answer was <literal>0</literal>, then there are
            no boards with IDs above X. Now probe asks if there are any
            boards below <literal>X</literal>. If so, probe knows there are
            boards with a model numbers below X. Probe then asks for boards
            greater than X-(limit/4) to go off-line. If repeats the query.
            By repeating this semi-binary search of IDs-in-range enough
            times, the probing code will eventually identify all PnP boards
            present in a given machine with a number of iterations that is
            much lower than what 2^64 would take.</para>

          <para>The IDs are two 32-bit fields (hence 2&circ;64) + 8 bit
            checksum. The first 32 bits are a vendor identifier. They never
            come out and say it, but it appears to be assumed that
            different types of boards from the same vendor could have
            different 32-bit vendor ids. The idea of needing 32 bits just
            for unique manufacturers is a bit excessive.</para>

          <para>The lower 32 bits are a serial #, Ethernet address,
            something that makes this one board unique. The vendor must
            never produce a second board that has the same lower 32 bits
            unless the upper 32 bits are also different. So you can have
            multiple boards of the same type in the machine and the full 64
            bits will still be unique.</para>

          <para>The 32 bit groups can never be all zero.  This allows the
            wired-OR to show non-zero bits during the initial binary
            search.</para>

          <para>Once the system has identified all the board IDs present,
            it will reactivate each board, one at a time (via the same I/O
            ports), and find out what resources the given board needs, what
            interrupt choices are available, etc. A scan is made over all
            the boards to collect this information.</para>

          <para>This info is then combined with info from any ECU files
            on the hard disk or wired into the MLB BIOS. The ECU and BIOS
            PnP support for hardware on the MLB is usually synthetic, and
            the peripherals do not really do genuine PnP. However by
            examining the BIOS info plus the ECU info, the probe routines
            can cause the devices that are PnP to avoid those devices the
            probe code cannot relocate.</para>

          <para>Then the PnP devices are visited once more and given
            their I/O, DMA, IRQ and Memory-map address assignments. The
            devices will then appear at those locations and remain there
            until the next reboot, although there is nothing that says you
            cannot move them around whenever you want.</para>

          <para>There is a lot of oversimplification above, but you
            should get the general idea.</para>

          <para>Microsoft took over some of the primary printer status
            ports to do PnP, on the logic that no boards decoded those
            addresses for the opposing I/O cycles. I found a genuine IBM
            printer board that did decode writes of the status port during
            the early PnP proposal review period, but MS said
            <quote>tough</quote>. So they do a write to the printer status
            port for setting addresses, plus that use that address +
            <literal>0x800</literal>, and a third I/O port for reading that
            can be located anywhere between <literal>0x200</literal> and
            <literal>0x3ff</literal>.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="major-numbers">
          <para>Can you assign a major number for a device driver I have
            written?</para>
        </question>

        <answer>

          <para>This depends on whether or not you plan on making the
            driver publicly available. If you do, then please send us a
            copy of the driver source code, plus the appropriate
            modifications to <filename>files.i386</filename>, a
            sample configuration file entry, and the appropriate
            &man.MAKEDEV.8;
            code to create any special files your device uses. If you do
            not, or are unable to because of licensing restrictions, then
            character major number 32 and block major number 8 have been
            reserved specifically for this purpose; please use them. In any
            case, we would appreciate hearing about your driver on
            &a.hackers;.</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="alternate-directory-layout">
          <para>What about alternative layout policies for
            directories?</para>
        </question>

        <answer>
          <para>In answer to the question of alternative layout policies
            for directories, the scheme that is currently in use is
            unchanged from what I wrote in 1983. I wrote that policy for
            the original fast filesystem, and never revisited it. It works
            well at keeping cylinder groups from filling up. As several of
            you have noted, it works poorly for find. Most filesystems are
            created from archives that were created by a depth first search
            (aka ftw). These directories end up being striped across the
            cylinder groups thus creating a worst possible scenario for
            future depth first searches. If one knew the total number of
            directories to be created, the solution would be to create
            (total / fs_ncg) per cylinder group before moving on.
            Obviously, one would have to create some heuristic to guess at
            this number. Even using a small fixed number like say 10 would
            make an order of magnitude improvement. To differentiate
            restores from normal operation (when the current algorithm is
            probably more sensible), you could use the clustering of up to
            10 if they were all done within a ten second window. Anyway, my
            conclusion is that this is an area ripe for
            experimentation.</para>

          <para>Kirk McKusick, September 1998</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="kernel-panic-troubleshooting">
          <para>How can I make the most of the data I see when my kernel
            panics?</para>
        </question>

        <answer>
          <para><emphasis>[This section was extracted from a mail
            written by &a.wpaul; on the freebsd-current
            <link linkend="mailing">mailing list</link> by &a.des;, who
            fixed a few typos and added the bracketed comments]
            </emphasis></para>

          <programlisting>From: Bill Paul &lt;wpaul@skynet.ctr.columbia.edu&gt;
Subject: Re: the fs fun never stops
To: Ben Rosengart
Date: Sun, 20 Sep 1998 15:22:50 -0400 (EDT)
Cc: current@FreeBSD.org</programlisting>

          <para><emphasis>Ben Rosengart posted the following
            panic message]</emphasis></para>

          <programlisting>&gt; Fatal trap 12: page fault while in kernel mode
&gt; fault virtual address   = 0x40
&gt; fault code              = supervisor read, page not present
&gt; instruction pointer     = 0x8:0xf014a7e5
                                ^^^^^^^^^^
&gt; stack pointer           = 0x10:0xf4ed6f24
&gt; frame pointer           = 0x10:0xf4ed6f28
&gt; code segment            = base 0x0, limit 0xfffff, type 0x1b
&gt;                         = DPL 0, pres 1, def32 1, gran 1
&gt; processor eflags        = interrupt enabled, resume, IOPL = 0
&gt; current process         = 80 (mount)
&gt; interrupt mask          =
&gt; trap number             = 12
&gt; panic: page fault</programlisting>

          <para>[When] you see a message like this, it is not enough to just
            reproduce it and send it in. The instruction pointer value that
            I highlighted up there is important; unfortunately, it is also
            configuration dependent. In other words, the value varies
            depending on the exact kernel image that you are using. If
            you are using a GENERIC kernel image from one of the snapshots,
            then it is possible for somebody else to track down the
            offending function, but if you are running a custom kernel then
            only <emphasis>you</emphasis> can tell us where the fault
            occurred.</para>

          <para>What you should do is this:</para>

            <procedure>
              <step>
                <para>Write down the instruction pointer value. Note that
                  the <literal>0x8:</literal> part at the beginning is not
                  significant in this case: it is the
                  <literal>0xf0xxxxxx</literal> part that we want.</para>
              </step>

              <step>
                <para>When the system reboots, do the following:

                  <screen>&prompt.user; <userinput>nm -n /kernel.that.caused.the.panic | grep f0xxxxxx</userinput></screen>

                  where <literal>f0xxxxxx</literal> is the instruction
                  pointer value. The odds are you will not get an exact
                  match since the symbols in the kernel symbol table are
                  for the entry points of functions and the instruction
                  pointer address will be somewhere inside a function, not
                  at the start. If you do not get an exact match, omit the
                  last digit from the instruction pointer value and try
                  again, i.e.:

                  <screen>&prompt.user; <userinput>nm -n /kernel.that.caused.the.panic | grep f0xxxxx</userinput></screen>

                   If that does not yield any results, chop off another
                   digit. Repeat until you get some sort of output. The
                   result will be a possible list of functions which caused
                   the panic. This is a less than exact mechanism for
                   tracking down the point of failure, but it is better than
                   nothing.</para>
              </step>
            </procedure>

          <para>I see people constantly show panic messages like this
            but rarely do I see someone take the time to match up the
            instruction pointer with a function in the kernel symbol
            table.</para>

          <para>The best way to track down the cause of a panic is by
            capturing a crash dump, then using
            &man.gdb.1; to generate a stack trace on the
            crash dump.</para>

          <para>In any case, the method I normally use is this:</para>

            <procedure>
              <step>
                <para>Set up a kernel config file, optionally adding
                  <literal>options DDB</literal> if you think you need
                  the kernel debugger for something. (I use this mainly
                  for setting breakpoints if I suspect an infinite loop
                  condition of some kind.)</para>
              </step>

              <step>
                <para>Use <command>config -g
                  <replaceable>KERNELCONFIG</replaceable></command> to set
                  up the build directory.</para>
              </step>

              <step>
                <para><command>cd /sys/compile/
                  <replaceable>KERNELCONFIG</replaceable>; make
                  </command></para>
              </step>

              <step>
                <para>Wait for kernel to finish compiling.</para>
              </step>

              <step>
                <para><command>make install</command></para>
              </step>

              <step>
                <para>reboot</para>
              </step>
            </procedure>

          <para>The &man.make.1; process will have built two kernels.
            <filename>kernel</filename> and
            <filename>kernel.debug</filename>.  <filename>kernel</filename>
            was installed as <filename>/kernel</filename>, while
            <filename>kernel.debug</filename> can be used as the source of
            debugging symbols for &man.gdb.1;.</para>

          <para>To make sure you capture a crash dump, you need edit
            <filename>/etc/rc.conf</filename> and set
            <literal>dumpdev</literal> to point to your swap
            partition. This will cause the &man.rc.8; scripts
            to use the &man.dumpon.8; command to enable crash
            dumps. You can also run &man.dumpon.8; manually.
            After a panic, the crash dump can be recovered using
            &man.savecore.8;; if
            <literal>dumpdev</literal> is set in
            <filename>/etc/rc.conf</filename>, the &man.rc.8;
            scripts will run &man.savecore.8; automatically
            and put the crash dump in
            <filename>/var/crash</filename>.</para>

            <note>
              <para>FreeBSD crash dumps are usually the same size as the
                physical RAM size of your machine. That is, if you have
                64MB of RAM, you will get a 64MB crash dump. Therefore you
                must make sure there is enough space in
                <filename>/var/crash</filename> to hold the dump.
                Alternatively, you run &man.savecore.8;
                manually and have it recover the crash dump to another
                directory where you have more room. It is possible to limit
                the size of the crash dump by using <literal>options
                MAXMEM=(foo)</literal> to set the amount of memory the
                kernel will use to something a little more sensible. For
                example, if you have 128MB of RAM, you can limit the
                kernel's memory usage to 16MB so that your crash dump size
                will be 16MB instead of 128MB.</para>
            </note>

          <para>Once you have recovered the crash dump, you can get a
            stack trace with &man.gdb.1; as follows:</para>

          <screen>&prompt.user; <userinput>gdb -k /sys/compile/KERNELCONFIG/kernel.debug /var/crash/vmcore.0</userinput>
<prompt>(gdb)</prompt> <userinput>where</userinput></screen>

          <para>Note that there may be several screens worth of
            information; ideally you should use
            &man.script.1; to capture all of them. Using the
            unstripped kernel image with all the debug symbols should show
            the exact line of kernel source code where the panic occurred.
            Usually you have to read the stack trace from the bottom up in
            order to trace the exact sequence of events that lead to the
            crash. You can also use &man.gdb.1; to print out
            the contents of various variables or structures in order to
            examine the system state at the time of the crash.</para>

          <para>Now, if you are really insane and have a second computer,
            you can also configure &man.gdb.1; to do remote
            debugging such that you can use &man.gdb.1; on
            one system to debug the kernel on another system, including
            setting breakpoints, single-stepping through the kernel code,
            just like you can do with a normal user-mode program. I have not
            played with this yet as I do not often have the chance to set up
            two machines side by side for debugging purposes.</para>

          <para><emphasis>[Bill adds: "I forgot to mention one thing: if
            you have DDB enabled and the kernel drops into the debugger,
            you can force a panic (and a crash dump) just by typing 'panic'
            at the ddb prompt. It may stop in the debugger again during the
            panic phase. If it does, type 'continue' and it will finish the
            crash dump." -ed]</emphasis></para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="dlsym-failure">
          <para>Why has dlsym() stopped working for ELF executables?</para>
        </question>

        <answer>
          <para>The ELF toolchain does not, by default, make the symbols
            defined in an executable visible to the dynamic linker.
            Consequently <function>dlsym()</function> searches on handles
            obtained from calls to <function>dlopen(NULL,
            flags)</function> will fail to find such symbols.</para>

          <para>If you want to search, using <function>dlsym()</function>,
            for symbols present in the main executable of a process, you
            need to link the executable using the
            <option>-export-dynamic</option> option to the
            ELF
            linker (&man.ld.1;).</para>
        </answer>
      </qandaentry>

      <qandaentry>
        <question id="change-kernel-address-space">
          <para>How can I increase or reduce the kernel address space?</para>
        </question>

        <answer>
          <para>By default, the kernel address space is 256 MB on
            FreeBSD 3.x and 1 GB on FreeBSD 4.x. If you run a
            network-intensive server (e.g. a large FTP or HTTP server),
            you might find that 256 MB is not enough.</para>

          <para>So how do you increase the address space? There are two
            aspects to this. First, you need to tell the kernel to reserve
            a larger portion of the address space for itself. Second, since
            the kernel is loaded at the top of the address space, you need
            to lower the load address so it does not bump its head against
            the ceiling.</para>

          <para>The first goal is achieved by increasing the value of
            <literal>NKPDE</literal> in
            <filename>src/sys/i386/include/pmap.h</filename>. Here is what
            it looks like for a 1 GB address space:</para>

          <programlisting>#ifndef NKPDE
#ifdef SMP
#define NKPDE                   254     /* addressable number of page tables/pde's */
#else
#define NKPDE                   255     /* addressable number of page tables/pde's */
#endif  /* SMP */
#endif</programlisting>

          <para>To find the correct value of <literal>NKPDE</literal>,
            divide the desired address space size (in megabytes) by four,
            then subtract one for UP and two for SMP.</para>

          <para>To achieve the second goal, you need to compute the
            correct load address: simply subtract the address space size
            (in bytes) from 0x100100000; the result is 0xc0100000 for a 1
            GB address space. Set <symbol>LOAD_ADDRESS</symbol> in
            <filename>src/sys/i386/conf/Makefile.i386</filename> to that
            value; then set the location counter in the beginning of the
            section listing in
            <filename>src/sys/i386/conf/kernel.script</filename> to the
            same value, as follows:</para>

          <programlisting>OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386")
OUTPUT_ARCH(i386)
ENTRY(btext)
SEARCH_DIR(/usr/lib); SEARCH_DIR(/usr/obj/elf/home/src/tmp/usr/i386-unknown-freebsdelf/lib);
SECTIONS
{
  /* Read-only sections, merged into text segment: */
  . = 0xc0100000 + SIZEOF_HEADERS;
  .interp     : { *(.interp)    }</programlisting>

          <para>Then reconfig and rebuild your kernel. You will probably
            have problems with &man.ps.1;
            &man.top.1; and the like; <command>make
            world</command> should take care of it (or a manual rebuild of
            <filename>libkvm</filename>,
            &man.ps.1; and &man.top.1;
            after copying the patched <filename>pmap.h</filename> to
            <filename>/usr/include/vm/</filename>.</para>

          <para>NOTE: the size of the kernel address space must be a
            multiple of four megabytes.</para>

          <para>[&a.dg; adds: <emphasis>I think the kernel address space
            needs to be a power of two, but I am not certain about that. The
          old(er) boot code used to monkey with the high order address bits
          and I think expected at least 256MB
          granularity.]</emphasis></para>
        </answer>
      </qandaentry>
    </qandaset>
  </chapter>

  <chapter id="acknowledgments">
    <title>Acknowledgments</title>

    <blockquote>
       <attribution>FreeBSD Core Team</attribution>

       <para>If you see a problem with this FAQ, or wish to submit an
         entry, please mail the &a.faq;.  We appreciate your feedback,
         and cannot make this a better FAQ without your help!</para>
    </blockquote>

      <variablelist>
        <varlistentry>
          <term>&a.jkh;</term>
            <listitem>
              <para>Occasional fits of FAQ-reshuffling and updating.</para>
            </listitem>
          </varlistentry>

          <varlistentry>
            <term>&a.dwhite;</term>

            <listitem>
              <para>Services above and beyond the call of duty on
                freebsd-questions</para>
            </listitem>
          </varlistentry>

          <varlistentry>
            <term>&a.joerg;</term>

            <listitem>
              <para>Services above and beyond the call of duty on
                Usenet</para>
            </listitem>
          </varlistentry>

          <varlistentry>
            <term>&a.wollman;</term>

            <listitem>
              <para>Networking and formatting</para>
            </listitem>
          </varlistentry>

          <varlistentry>
            <term>Jim Lowe</term>

            <listitem>
              <para>Multicast information</para>
            </listitem>
          </varlistentry>

          <varlistentry>
            <term>&a.pds;</term>

            <listitem>
              <para>FreeBSD FAQ typing machine slavey</para>
            </listitem>
          </varlistentry>

          <varlistentry>
            <term>The FreeBSD Team</term>

            <listitem>
              <para>Kvetching, moaning, submitting data</para>

            </listitem>
          </varlistentry>
        </variablelist>

    <para>And to any others we have forgotten, apologies and heartfelt
      thanks!</para>
  </chapter>

  &bibliography;
</book>
