7.14. Cleaning up and Saving the Temporary System

7.14.1. Cleaning

First, remove the currently installed documentation to prevent them from ending up in the final system, and to save about 35 MB:

rm -rf /usr/share/{info,man,doc}/*

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:

find /usr/{lib,libexec} -name \*.la -delete

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:

rm -rf /tools

7.14.2. Backup

[Note]

Note

All the remaining steps in this section are optional. Nevertheless, as soon as you begin installing packages in Chapter 8, the temporary files will be overwritten. So it may be a good idea to do a backup of the current system as described below.

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 $LFS hierarchy for safety reasons.

[Important]

Important

All of the following instructions are executed by root. 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 LFS is set for user lfs by default but may not be set for root. Whenever commands are to be executed by root, make sure you have set LFS. This has been discussed in Section 2.6, “Setting The $LFS Variable”.

Now, if you are making a backup, leave the chroot environment:

exit

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.

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 root.

Before we make a backup, unmount the virtual file systems:

umount $LFS/dev{/pts,}
umount $LFS/{sys,proc,run}

Create the backup archive by running the following command:

[Note]

Note

Because the backup archive is compressed, it takes a relatively long time (over 10 minutes) even on a resonably fast system.

Also, ensure the LFS environment variable is set for the root user.

cd $LFS 
tar -cJpf $HOME/lfs-temp-tools-11.0-systemd-rc3.tar.xz .

Replace $HOME by a directory of your choice if you do not want to have the backup stored in root's home directory.

7.14.3. Restore

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 $LFS, they are included in the backup archive as well, so they do not need to be downloaded again. After checking that $LFS is set properly, restore the backup by executing the following commands:

[Warning]

Warning

The following commands are extremly dangerous. If you run rm -rf ./* as the root user and you do not change to the $LFS directory or the LFS environment variable is not set for the root user, it will destroy your entire host system. YOU ARE WARNED.

cd $LFS 
rm -rf ./* 
tar -xpf $HOME/lfs-temp-tools-11.0-systemd-rc3.tar.xz

Again, double check that the environment has been setup properly and continue building the rest of the system.

[Important]

Important

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 (findmnt | grep $LFS). If they are not mounted, remount them now as described in Section 7.3, “Preparing Virtual Kernel File Systems” and re-enter the chroot environment (see Section 7.4, “Entering the Chroot Environment”) before continuing.