makeworld.html

FreeBSD操作系统的详细使用手册

Base System</a></h3>

<p>You must be in the <tt class="FILENAME">/usr/src</tt> directory:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">cd /usr/src</kbd>
</pre>

<p>(unless, of course, your source code is elsewhere, in which case change to that
directory instead).</p>

<p>To rebuild the world you use the <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=make&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">make</span>(1)</span></a> command. This
command reads instructions from the <tt class="FILENAME">Makefile</tt>, which describes
how the programs that comprise FreeBSD should be rebuilt, the order in which they should
be built, and so on.</p>

<p>The general format of the command line you will type is as follows:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">make -<var
class="REPLACEABLE">x</var> -D<var class="REPLACEABLE">VARIABLE</var> <var
class="REPLACEABLE">target</var></kbd>
</pre>

<p>In this example, <var class="OPTION">-<var class="REPLACEABLE">x</var></var> is an
option that you would pass to <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=make&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">make</span>(1)</span></a>. See the <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=make&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">make</span>(1)</span></a> manual page
for an example of the options you can pass.</p>

<p><var class="OPTION">-D<var class="REPLACEABLE">VARIABLE</var></var> passes a variable
to the <tt class="FILENAME">Makefile</tt>. The behavior of the <tt
class="FILENAME">Makefile</tt> is controlled by these variables. These are the same
variables as are set in <tt class="FILENAME">/etc/make.conf</tt>, and this provides
another way of setting them.</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">make -DNOPROFILE <var
class="REPLACEABLE">target</var></kbd>
</pre>

<p>is another way of specifying that profiled libraries should not be built, and
corresponds with the</p>

<pre class="PROGRAMLISTING">
NOPROFILE=    true     #    Avoid compiling profiled libraries
</pre>

<p>line in <tt class="FILENAME">/etc/make.conf</tt>.</p>

<p><var class="REPLACEABLE">target</var> tells <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=make&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">make</span>(1)</span></a> what you want
to do. Each <tt class="FILENAME">Makefile</tt> defines a number of different ``targets'',
and your choice of target determines what happens.</p>

<p>Some targets are listed in the <tt class="FILENAME">Makefile</tt>, but are not meant
for you to run. Instead, they are used by the build process to break out the steps
necessary to rebuild the system into a number of sub-steps.</p>

<p>Most of the time you will not need to pass any parameters to <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=make&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">make</span>(1)</span></a>, and so your
command like will look like this:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">make <var
class="REPLACEABLE">target</var></kbd>
</pre>

<p>Beginning with version 2.2.5 of FreeBSD (actually, it was first created on the
FreeBSD-CURRENT branch, and then retrofitted to FreeBSD-STABLE midway between 2.2.2 and
2.2.5) the <tt class="MAKETARGET">world</tt> target has been split in two: <tt
class="MAKETARGET">buildworld</tt> and <tt class="MAKETARGET">installworld</tt>.
Beginning with version 5.3 of FreeBSD the <tt class="MAKETARGET">world</tt> target will
be changed so it will not work at all by default because it is actually dangerous for
most users.</p>

<p>As the names imply, <tt class="MAKETARGET">buildworld</tt> builds a complete new tree
under <tt class="FILENAME">/usr/obj</tt>, and <tt class="MAKETARGET">installworld</tt>
installs this tree on the current machine.</p>

<p>This is very useful for 2 reasons. First, it allows you to do the build safe in the
knowledge that no components of your running system will be affected. The build is ``self
hosted''. Because of this, you can safely run <tt class="MAKETARGET">buildworld</tt> on a
machine running in multi-user mode with no fear of ill-effects. It is still recommended
that you run the <tt class="MAKETARGET">installworld</tt> part in single user mode,
though.</p>

<p>Secondly, it allows you to use NFS mounts to upgrade multiple machines on your
network. If you have three machines, <tt class="HOSTID">A</tt>, <tt class="HOSTID">B</tt>
and <tt class="HOSTID">C</tt> that you want to upgrade, run <tt class="COMMAND">make
buildworld</tt> and <tt class="COMMAND">make installworld</tt> on <tt
class="HOSTID">A</tt>. <tt class="HOSTID">B</tt> and <tt class="HOSTID">C</tt> should
then NFS mount <tt class="FILENAME">/usr/src</tt> and <tt class="FILENAME">/usr/obj</tt>
from <tt class="HOSTID">A</tt>, and you can then run <tt class="COMMAND">make
installworld</tt> to install the results of the build on <tt class="HOSTID">B</tt> and
<tt class="HOSTID">C</tt>.</p>

<p>Although the <tt class="MAKETARGET">world</tt> target still exists, you are strongly
encouraged not to use it.</p>

<p>Run</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">make buildworld</kbd>
</pre>

<p>It is now possible to specify a <var class="OPTION">-j</var> option to <tt
class="COMMAND">make</tt> which will cause it to spawn several simultaneous processes.
This is most useful on multi-CPU machines. However, since much of the compiling process
is IO bound rather than CPU bound it is also useful on single CPU machines.</p>

<p>On a typical single-CPU machine you would run:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">make -j4 buildworld</kbd>
</pre>

<p><a href="http://www.FreeBSD.org/cgi/man.cgi?query=make&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">make</span>(1)</span></a> will then have
up to 4 processes running at any one time. Empirical evidence posted to the mailing lists
shows this generally gives the best performance benefit.</p>

<p>If you have a multi-CPU machine and you are using an SMP configured kernel try values
between 6 and 10 and see how they speed things up.</p>

<p>Be aware that this is still somewhat experimental, and commits to the source tree may
occasionally break this feature. If the world fails to compile using this parameter try
again without it before you report any problems.</p>
</div>

<div class="SECT3">
<h3 class="SECT3"><a id="AEN27762" name="AEN27762">19.4.7.3 Timings</a></h3>

<p>Many factors influence the build time, but currently a 500&nbsp;MHz <span
class="TRADEMARK">Pentium</span>&reg;&nbsp;III with 128&nbsp;MB of RAM takes about
2&nbsp;hours to build the FreeBSD-STABLE tree, with no tricks or shortcuts used during
the process. A FreeBSD-CURRENT tree will take somewhat longer.</p>
</div>
</div>

<div class="SECT2">
<h2 class="SECT2"><a id="AEN27770" name="AEN27770">19.4.8 Compile and Install a New
Kernel</a></h2>

<p>To take full advantage of your new system you should recompile the kernel. This is
practically a necessity, as certain memory structures may have changed, and programs like
<a href="http://www.FreeBSD.org/cgi/man.cgi?query=ps&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">ps</span>(1)</span></a> and <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=top&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">top</span>(1)</span></a> will fail to
work until the kernel and source code versions are the same.</p>

<p>The simplest, safest way to do this is to build and install a kernel based on <tt
class="FILENAME">GENERIC</tt>. While <tt class="FILENAME">GENERIC</tt> may not have all
the necessary devices for your system, it should contain everything necessary to boot
your system back to single user mode. This is a good test that the new system works
properly. After booting from <tt class="FILENAME">GENERIC</tt> and verifying that your
system works you can then build a new kernel based on your normal kernel configuration
file.</p>

<p>On modern versions of FreeBSD it is important to <a
href="makeworld.html#MAKE-BUILDWORLD">build world</a> before building a new kernel.</p>

<div class="NOTE">
<blockquote class="NOTE">
<p><b>Note:</b> If you want to build a custom kernel, and already have a configuration
file, just use <var class="LITERAL">KERNCONF=<var
class="REPLACEABLE">MYKERNEL</var></var> like this:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">cd /usr/src</kbd>
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">make buildkernel KERNCONF=<var
class="REPLACEABLE">MYKERNEL</var></kbd>
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">make installkernel KERNCONF=<var
class="REPLACEABLE">MYKERNEL</var></kbd>
</pre>

<p>In FreeBSD&nbsp;4.2 and older you must replace <var class="LITERAL">KERNCONF=</var>
with <var class="LITERAL">KERNEL=</var>. 4.2-STABLE that was fetched before Feb 2nd, 2001
does not recognize <var class="LITERAL">KERNCONF=</var>.</p>
</blockquote>
</div>

<p>Note that if you have raised <var class="LITERAL">kern.securelevel</var> above 1 <span
class="emphasis"><i class="EMPHASIS">and</i></span> you have set either the <var
class="LITERAL">noschg</var> or similar flags to your kernel binary, you might find it
necessary to drop into single user mode to use <tt class="MAKETARGET">installkernel</tt>.
Otherwise you should be able to run both these commands from multi user mode without
problems. See <a href="http://www.FreeBSD.org/cgi/man.cgi?query=init&sektion=8"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">init</span>(8)</span></a> for details
about <var class="LITERAL">kern.securelevel</var> and <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=chflags&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">chflags</span>(1)</span></a> for details
about the various file flags.</p>

<p>If you are upgrading to a version of FreeBSD below 4.0 you should use the old kernel
build procedure. However, it is recommended that you use the new version of <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=config&sektion=8"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">config</span>(8)</span></a>, using a
command line like this.</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd
class="USERINPUT">/usr/obj/usr/src/usr.sbin/config/config <var
class="REPLACEABLE">KERNELNAME</var></kbd>
</pre>
</div>

<div class="SECT2">
<h2 class="SECT2"><a id="AEN27825" name="AEN27825">19.4.9 Reboot into Single User
Mode</a></h2>

<p>You should reboot into single user mode to test the new kernel works. Do this by
following the instructions in <a href="makeworld.html#MAKEWORLD-SINGLEUSER">Section
19.4.5</a>.</p>
</div>

<div class="SECT2">
<h2 class="SECT2"><a id="AEN27831" name="AEN27831">19.4.10 Install the New System
Binaries</a></h2>

<p>If you were building a version of FreeBSD recent enough to have used <tt
class="COMMAND">make buildworld</tt> then you should now use <tt
class="MAKETARGET">installworld</tt> to install the new system binaries.</p>

<p>Run</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">cd /usr/src</kbd>
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">make installworld</kbd>
</pre>

<div class="NOTE">
<blockquote class="NOTE">
<p><b>Note:</b> If you specified variables on the <tt class="COMMAND">make
buildworld</tt> command line, you must specify the same variables in the <tt
class="COMMAND">make installworld</tt> command line. This does not necessarily hold true
for other options; for example, <var class="OPTION">-j</var> must never be used with <tt
class="MAKETARGET">installworld</tt>.</p>

<p>For example, if you ran:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">make -DNOPROFILE buildworld</kbd>
</pre>

<p>you must install the results with:</p>

<pre class="SCREEN">
<samp class="PROMPT">#</samp> <kbd class="USERINPUT">make -DNOPROFILE installworld</kbd>
</pre>

<p>otherwise it would try to install profiled libraries that had not been built during
the <tt class="COMMAND">make buildworld</tt> phase.</p>
</blockquote>
</div>
</div>

<div class="SECT2">
<h2 class="SECT2"><a id="AEN27858" name="AEN27858">19.4.11 Update Files Not Updated by
<tt class="COMMAND">make installworld</tt></a></h2>

<p>Remaking the world will not update certain directories (in particular, <tt
class="FILENAME">/etc</tt>, <tt class="FILENAME">/var</tt> and <tt
class="FILENAME">/usr</tt>) with new or changed configuration files.</p>

<p>The simplest way to update these files is to use <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=mergemaster&sektion=8"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">mergemaster</span>(8)</span></a>, though
it is possible to do it manually if you would prefer to do that. Regardless of which way
you choose, be sure to make a backup of <tt class="FILENAME">/etc</tt> in case anything
goes wrong.</p>

<div class="SECT3">
<h3 class="SECT3"><a id="MERGEMASTER" name="MERGEMASTER">19.4.11.1 <tt
class="COMMAND">mergemaster</tt></a></h3>

<i class="AUTHORGROUP"><span class="CONTRIB">Contributed by</span> Tom Rhodes.</i> 

<p>The <a href="http://www.FreeBSD.org/cgi/man.cgi?query=mergemaster&sektion=8"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">mergemaster</span>(8)</span></a> utility
is a Bourne script that will aid you in determining the differences between your
configuration files in <tt class="FILENAME">/etc</tt>, and the configuration files in the
source tree <tt class="FILENAME">/usr/src/etc</tt>. This is the recommended solution for
keeping the system configuration files up to date with those located in the source
tree.</p>

<p><tt class="COMMAND">mergemaster</tt> was integrated into the FreeBSD base system
between 3.3-RELEASE and 3.4-RELEASE, which means it is present in all -STABLE and
-CURRENT systems since 3.3.</p>

<p>To begin simply type <tt class="COMMAND">mergemaster</tt> at your prompt, and watch it
start going. <tt class="COMMAND">mergemaster</tt> will then build a temporary root
environment, from <tt class="FILENAME">/</tt> down, and populate it with various system
configuration files. Those files are then compared to the ones currently installed in
your system. At this point, files that differ will be shown in <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=diff&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">diff</span>(1)</span></a> format, with
the <var class="OPTION">+</var> sign representing added or modified lines, and <var
class="OPTION">-</var> representing lines that will be either removed completely, or
replaced with a new line. See the <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=diff&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">diff</span>(1)</span></a> manual page
for more information about the <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=diff&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">diff</span>(1)</span></a> syntax and how
file differences are shown.</p>

<p><a href="http://www.FreeBSD.org/cgi/man.cgi?query=mergemaster&sektion=8"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">mergemaster</span>(8)</span></a> will
then show you each file that displays variances, and at this point you will have the
option of either deleting the new file (referred to as the temporary file), installing
the temporary file in its unmodified state, merging the temporary file with the currently
installed file, or viewing the <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=diff&sektion=1"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">diff</span>(1)</span></a> results
again.</p>

<p>Choosing to delete the temporary file will tell <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=mergemaster&sektion=8"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">mergemaster</span>(8)</span></a> that we
wish to keep our current file unchanged, and to delete the new version. This option is
not recommended, unless you see no reason to change the current file. You can get help at
any time by typing <b class="KEYCAP">?</b> at the <a
href="http://www.FreeBSD.org/cgi/man.cgi?query=mergemaster&sektion=8"><span
class="CITEREFENTRY"><span class="REFENTRYTITLE">mergemaster</span>(8)</span></a> prompt.
If the user chooses to skip a file, it will be presented again after all other files have
been dealt with.</p>

<p>Choosing to install the unmodified temporary file will replace the current file with
the new one. For most unmodified files, this is the best option.</p>

<p>Choosing to merge the file will present you with a text editor, and the contents of