This may be common knowledge but I always forget this after a few weeks:
How do I know when the server was restarted? I've always gone with what I call the "lazy" way by just looking at the uptime for the NIC but we all know that may not be accurate if there was ever a disconnect to the network. The proper way is to look for "Event 6009". Whenever a server restarts, this Event ID is always logged.
In case you noticed, yes, this is a Cisco Unity deployment in VI3. We deployed one of these for our clients as soon as Cisco supported Unity in a virtualized environment.