Techrepublic has a useful article that illustrates backing up on a Linux system using a few commonly available tools. The author uses rsync, which is used to synchronize files between two system, ssh to authenticate to a remote machine, tar for creating an easily movable archive, and cron to schedule the backups automagically.
Every IT administrator knows a good backup plan is an absolute necessity for successful disaster recovery. For many, the backup plan seems to always begin with the purchase of proprietary systems that are often costly, unreliable, and not terribly adept. Fortunately, Linux has a solution that is -- like the operating system itself -- cost-effective, reliable, and flexible.
The beauty of this system is that nearly all modern Linux distributions already have all the tools you need to set it up. The only detail not included is a bit of imagination, a piece of hardware to send the backup files to, and some time to script the files.
The article steps through setting up the server to accept rsync and SSH calls, before writing the scripts to do the backups. It also shows you how to create public and private SSH keys, required for authenticating, and then placing them on the proper machines.[Read More]