I've never used it, but suse provides an auto-yast function that will duplicate everything after an install, ie all packages, as well as other system configuration options. At the very end of the install, on the screen that basically says done, there is a button that says "duplicate this server with autoyast".
Here's a link that mentions it, 2nd to last paragraph:
http://madpenguin.org/cms/index.php/...id=7150&page=2