I use BackupPC at home to backup my systems to an external hard drive.
The *NIX systems that are being backed up just need ssh, rsync, and an
account with permission to run rsync as root via sudo. It works really
well as rsync will only push over the changed files, and then BackupPC
maintains it's archive with lots of symlinks and such. The external
hard drive used to be encrypted, but I had issues when moving the
drive from one computer to another so I gave up on the encryption and
settled on a laptop lock. I'm hoping to work out a deal with a friend
so that I can drop another external HD at his place and rsync the
BackupPC archive to the external HD at his place.

For the Windows system I'm BackupPC grabs data via smb sharing. I've
tried getting the rsync+ssh setup working on Windows but so far I've
only had mixed results.

BackupPC is nice for devices such as laptops which may not be on the
network. It can be configured to periodically ping hosts and back them
up when they are available on the network.

I've successfully recovered an entire Linux system via BackupPC. For
Windows, I only backup data (Documents and Settings directories). You
would need to involve nt backup or some other utility to do a full
restore of a Windows system.

I tried configuring Backula before BackupPC. In the end I found
Backula to be overly complicated for what I was doing.

-- 
Andrew S. Zbikowski | http://andy.zibnet.us
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