rsync is a really useful Linux/Unix platform utility for synchronizing files, and can also be used as a tool for backing up data from one machine to another, using large capacity hard disk drives as the main backup medium, thus creating duplicate sets of data.
rsync transfers only the changes in files, or newly created files, using the rsync algorithmi, compressing the differences on on the fly and transferring the data to the destination, making network file transfers very fast and efficient.
rsync was orignally developed by Andrew Tridgell.
rsync links (links open in a new window)
rsync home page: http://rsync.samba.org/
Mike Rubel's 'Easy Automated Snapshot-Style Backups with Linux and Rsync' page: http://www.mikerubel.org/computers/rsync_snapshots/
John C. Bowman's rlbackup (Remote Linked Backup) page: http://www.math.ualberta.ca/imaging/rlbackup/
Nathan Rosenquist's rsnapshot project: http://rsnapshot.org/
My wrapper bash script for creating rsnapshot configurations on a backup server: createbackupsettings.sh