I released the July updates onto our network this past weekend. I’d also deployed our new AV the previous week. Let’s just say that AV mixed with Hyper-V and followed by a reboot made for a nice mess.
I logged into the Hyper-V lab this morning to find half of my VM’s were missing. They’re sitting find (but idle) on the storage. It’s just Hyper-V has "forgotten" that they ever existed.
I trawled through the Windows Event logs (Application and Service logs – Microsoft – Windows – Hyper-V-Config – Admin) and found a series of these:
Event ID: 4096
The Virtual Machines configuration <big long GUID> at <path to VM> is no longer accessible: The requested operation cannot be performed on a file with a user-mapped section open. (0x800704C8)
Ok. A bit of googling found an entry on the TechNet forums that says you need to disable scanning for the VHD’s and the XML files of your VM’s. Ouch!
OK, so I did that and rebooted by lab server. Still no dice. Actually, Hyper-V doesn’t even bother attempting to load these VM’s now. OK, I’ll do what I would in any other virtualisation product; I’ll open them. Ick … no open command. Import? Nope; because MS in their wisdom (!) decided that the import/export format should be different to that of a normal VM.
So I’ve got a plethora of VM’s that are sitting on my disk in a saved state that I cannot load up. My only way forward is to re-add the virtual hard disks as new VM’s. This is a pain:
- I lose my saved states.
- I have to reconfigure every single VM that is missing.
- Each VM has to do the PNP dance with a "new" NIC and I have to reconfigure IPv4 addressing.
- It’s just lots of work I shouldn’t have to do.
I’ve logged a bug report with MS. I’m open to any constructive suggestions.