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<sect1 id="ch-tools-cleanup">
<?dbhtml filename="cleanup.html"?>
<title>Cleaning up and Saving the Temporary System</title>
<sect2>
<title>Cleaning</title>
<para>First, remove the currently installed documentation to prevent them
from ending up in the final system, and to save about 35 MB:</para>
<screen><userinput>rm -rf /usr/share/{info,man,doc}/*</userinput></screen>
<para>Second, the libtool .la files are only useful when linking with static
libraries. They are unneeded and potentially harmful when using dynamic
shared libraries, specially when using non-autotools build systems.
While still in chroot, remove those files now:</para>
<screen><userinput>find /usr/{lib,libexec} -name \*.la -delete</userinput></screen>
<para>
The current system size is now about 3 GB, however
the /tools directory is no longer needed. It uses about
1 GB of disk space. Delete it now:
</para>
<screen><userinput>rm -rf /tools</userinput></screen>
</sect2>
<sect2>
<title>Backup</title>
<note><para>
All the remaining steps in this section are optional. Nevertheless,
as soon as you begin installing packages in <xref
linkend="chapter-building-system"/>, the temporary files will be
overwritten. So it may be a good idea to do a backup of the current
system as described below.
</para></note>
<para>
The following steps are performed from outside the chroot
environment. That means, you have to leave the chroot environment
first before continuing. The reason for that is to
get access to file system locations outside of the chroot
environment to store/read the backup archive which should
not be placed within the
<filename class="directory">$LFS</filename> hierarchy for
safety reasons.
</para>
<important>
<para>All of the following instructions are executed by
<systemitem class="username">root</systemitem>. Take extra
care about the commands you're going to run as mistakes
here can modify your host system. Be aware that the
environment variable <envar>LFS</envar>
is set for user <systemitem class="username">lfs</systemitem> by default
but may <emphasis>not</emphasis> be set for
<systemitem class="username">root</systemitem>. Whenever
commands are to be executed by <systemitem class="username">root</systemitem>,
make sure you have set <envar>LFS</envar>.
This has been discussed in <xref linkend='ch-partitioning-aboutlfs'/>.
</para>
</important>
<para>
Now, if you are making a backup, leave the chroot environment:
</para>
<screen role="nodump"><userinput>exit</userinput></screen>
<para>
At this point the essential programs and libraries have been created
and your current system is in a good state. Your system can now be
backed up for later reuse. In case of fatal failures in the subsequent
chapters, it often turns out that removing everything and starting over
(more carefully) is the best option to recover. Unfortunately, all the
temporary files will be removed, too. To avoid spending extra time to
redo something which has been built successfully, prepare a backup.
</para>
<para>
Make sure you have at least 1 GB free disk space (the source tarballs
will be included in the backup archive) in the home directory of user
<systemitem class="username">root</systemitem>.
</para>
<para>Before we make a backup, unmount the virtual file systems:</para>
<screen role="nodump"><userinput>umount $LFS/dev{/pts,}
umount $LFS/{sys,proc,run}</userinput></screen>
<para>
Create the backup archive by running the following command:
</para>
<note>
<para>
Because the backup archive is compressed, it takes a relatively
long time (over 10 minutes) even on a resonably fast system.
</para>
<para>
Also, ensure the <envar>LFS</envar> environment variable is set
for the root user.
</para>
</note>
<screen role="nodump" revision="sysv"><userinput>cd $LFS
tar -cJpf $HOME/lfs-temp-tools-&version;.tar.xz .</userinput></screen>
<screen role="nodump" revision="systemd"><userinput>cd $LFS
tar -cJpf $HOME/lfs-temp-tools-&versiond;.tar.xz .</userinput></screen>
<para>
Replace <envar>$HOME</envar> by a directory of your choice if you
do not want to have the backup stored in <systemitem
class="username">root</systemitem>'s home directory.
</para>
</sect2>
<sect2>
<title>Restore</title>
<para>
In case some mistakes have been made and you need to start over, you can
use this backup to restore the system and save some recovery time.
Since the sources are located under
<filename class="directory">$LFS</filename>, they are included in the
backup archive as well, so they do not need to be downloaded again. After
checking that <envar>$LFS</envar> is set properly,
restore the backup by executing the following commands:
</para>
<!-- Make the following look different so users don't blindly run the
restore when they don't need to. -->
<warning><para>The following commands are extremly dangerous. If
you run <command>rm -rf ./*</command> as the root user and you
do not change to the $LFS directory or the <envar>LFS</envar>
environment variable is not set for the root user, it will destroy
your entire host system. YOU ARE WARNED.</para></warning>
<screen role="nodump" revision="sysv"><computeroutput>cd $LFS
rm -rf ./*
tar -xpf $HOME/lfs-temp-tools-&version;.tar.xz</computeroutput></screen>
<screen role="nodump" revision="systemd"><computeroutput>cd $LFS
rm -rf ./*
tar -xpf $HOME/lfs-temp-tools-&versiond;.tar.xz</computeroutput></screen>
<para>
Again, double check that the environment has been setup properly
and continue building the rest of the system.
</para>
<important>
<para>
If you left the chroot environment to create a backup or restart
building using a restore, remember to check that the virtual
filesystems are still mounted (<command>findmnt | grep
$LFS</command>). If they are not mounted, remount them now as
described in <xref linkend='ch-tools-kernfs'/> and re-enter the chroot
environment (see <xref linkend='ch-tools-chroot'/>) before continuing.
</para>
</important>
</sect2>
</sect1>