Linux Alternative to Symantec NetBackup

partimage-server - server to use partimage across a network
partimage - backup partitions into a compressed image file
bacula - network backup, recovery and verification
backuppc - high-performance, enterprise-grade system for backing up PCs
clonezilla

http://linux.about.com/od/softbackup/Linux_Software_Backup_Solutions.htm

5 Free Linux Backup Solutions http://www.foogazi.com/2008/02/25/free-linux-backup-solutions/

Linux Online - Category: Administration / Backup http://www.linux.org/apps/all/Administration/Backup.html

I would highly recommend Clonezilla with a DRBL server setup. This can not only backup, but also push out images over the network. The one caveat is that it's not good to use with servers because those need to be online and working, so you'll need some other way to do those since Clonezilla does not support live imaging.

Another option would be to use dd, since this is essentially what Clonezilla does (only with a nicer GUI). There's also G4L, Ghost For Linux, which may be another option, but I don't believe it has the network support that Clonezilla does.

The key to doing backups/imaging, especially where databases are concerned, is to make sure that the backups are byte-for-byte, bit-for-bit EXACT duplicates.

Clonezilla http://clonezilla.org/

Something like this may be what you are looking for: https://launchpad.net/deja-dup