Linux System Administration

Backing Up User Data to a Server with rsync

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Backing Up User Data to a Server with rsync

The most critical data to back up is data that is impossible, or very costly, to re-cre-

ate. Usually this is user data that has grown over months or years of work. You can

typically restore system data relatively easily by reinstalling from the original distribu-

tion media.

We’ll focus here on making backups of user data from Linux desktop computers. A

backup server needs enough disk space to store all of your user files. A dedicated

machine is recommended. For a large office, disks may have a RAID (Redundant

Array of Independent Disks) configuration to further protect against multiple failures.

The Linux utility rsync is a copy program designed to replicate large quantities of

data. It can skip previously copied files and fragments and encrypt data transfers

with ssh, making remote backups with rsync faster and more secure than they are

with traditional tools like cp, cpio,ortar. To check whether rsync is on your system,

enter:

# rsync --help

bash: rsync: command not found

If you see that message, you have to get the rsync package. To install it in Debian,

enter:

# apt-get install rsync

Usually, you’ll want your backups to preserve the original ownership and permis-

sions. Thus, you’ll need to ensure that all users have accounts and home directories

on the backup server.

rsync Basics

The syntax of the rsync ...