Backing Up the Linux System
The backup server itself should be backed up, which constitutes a local backup procedure. Certain Linux network backup tools also resemble the local backup procedures. For these reasons, you should understand how to perform a local backup. This involves knowing what backup packages are available and how to use at least one. (I describe the tar command, which is often used when backing up to disk and tape media.) Because optical media are particularly complex, I also describe them in more detail. Finally, no backup is complete unless you can restore data from it, so I describe how to do this.
A Rundown of Linux Backup Packages
Backing up a computer is essentially a matter of copying files. Backup, though, presents certain unique challenges that aren’t present in many other file-copying operations. One of these is the preservation of file metadata. Some file copying techniques lose some types of metadata, but backup tools tend to preserve more metadata. Another unique backup challenge is use of tapes, CD-R drives, and other unusual media used for backups. Most Linux backup packages are either designed for use with tapes as well as or instead of disk files, or they use additional programs to help store the data on the backup media. Finally, backup media are often of limited capacity, so a method of compression is desirable. Some Linux backup tools include compression algorithms, but others rely on additional programs, such as gzip or bzip2, to compress a ...