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Reverting a snapshot means returning to an older random number generator state, which has the potential to completely break crypto. That's probably an unavoidable consequence of the feature, but users should to be aware of this - only I don't know how to make them aware. --Mitr 15:57, 20 July 2012 (UTC)

Reverting disk snapshots requires rebooting the VM, which I assume wouldn't cause crypt problems. It sounds like you're saying doing a memory + disk revert for a running VM could cause crypto issues, but if that's the case, our existing 'save/restore' support (basically a memory snapshot which forces the VM to turn off) would suffer the same problem. Granted that might just mean we should be warning users about that case as well, but it's a preexisting issue at least. --Crobinso 21:26, 22 July 2012 (UTC)