I have a few Xen 5.5 servers in production and presently I'm not happy with the snapshot feature to a NAS device. Seems there are a few issues with recovery of snapshots.
What I'm looking for is an automated script that will take the virtual servers offline (shutdown), export to a mounted NAS (I do this already with our NAS). Once the export is done, start the virtual servers backup.
What I have found with testing is that the export of the virtual server is the only real way to recover a virtual server to another Xen server without any issues.