I have a new Dell PowerEdge R900 Windows 2008 Standard x86 Hyper-V server with 8 Guests (7 are Windows Server 2008 Standard x64 and 1 is Windows Server 2008 Standard x86). I have BE Agent for MS Virtual Servers on the host which is making full 'online' guest OS backups successfully. The servers remain running during the backups and the VSS-aware applications and services (such as SQL 2008) are notified about the backup and all seems well.
However, when I restore a single VM, or all VM's, to the same Hyper-V host server, or to completely different Hyper-V box, the servers come out of restore in an 'Off' state, not a 'Saved' state. So, when I then start the VM guest manually, I get a "Windows Error Recovery" message during boot-up, and have to select 'Start Windows Normally"... Is this the way it should be? I always assumed, after reading up on the product, that the BE agent for MS Virtual Servers would allow me to do an online backup, without having to temporarily save the state of the guest OS, and then in the event of a failure restore the guest OS in a 'Saved' state so that it is fully intact and corruption-free.
If I turn off the "Backup (volume snapsot)" integration services for the guest OS's, it temporarily saves the state of the first guest (which takes approx 30-60 seconds each), creates a vss snapshot, starts the guest back up, backups that guest, and then moves onto the next guest in the list. Then, if I restore one of those guests, BE restores the guest in a 'Saved' state and I can then start the guest and continue right where I left off. This is great, except that you have a 30-60 second downtime per guest, which for many 24/7/365 environments is not ideal.
So, why does a BE restore restore to a 'Saved' state only when the "Backup (volume snapshot)" service is disabled? Shouldn't it also be fully capable of restoring in a 'Saved' state when the "Backup (volume snapshot)" integration service is on as well? It is backing up the files that contain a snapshot of the systems memory at the time of backup, so from what I can tell it has everything it needs for a proper 'Saved' state restore... but BE doesn't seem to want to restore it in a 'Saved' state.
I switched from my 'diskshadow' scripted backups (http://virtuallyaware.spaces.live.com/blog/cns!549C424F228D6040!153.entry
which had the same problem (not able to restore 'online' backups to a 'saved' state), because I thought BE Agent for MS Virtual Servers would have no problem restoring to a saved state since everything I read in documentation seemed to indicate it would as long as all the requirements were met (which in my case they have been).
Anyone care to comment? Thanks in advance!