> The most simple way is to back up your server with Time Machine. That happens to also be the only supported way.
However the OP's system version was 10.6.x Server. YMMV, but my experience trying to use TM to back up Snow Leopard Server has not been a positive one. TM works as expected for about a week, and then stalls out, never finishing its backup session despite plenty of free space on the destination volume.
Too bad, since I wouldn't mind using TM as a completely different method to supplement our normal nightly backup, but I've given up on it for now. If/when we update to 10.9 server I might try TM again.