I alluded to a second problem with VMM 2008 and Hyper-V earlier. The issue was that after a while, a previously healthy host would change to "requires attention". The virtualisation status would change to unknown and the agent would stop communicating. The host refresh would fail as follows:
Error (2927)
A Hardware Management error has occurred trying to contact server server.domain.local.
(Unknown error (0x80338104))
Recommended Action
Check that WinRM is installed and running on server server.domain.local. For more information use the command "winrm helpmsg hresult".
That WinRm error translates to "access denied". I confirmed all the networking stuff and WinRM were actually OK.
Not long after that, every VM on that Hyper-V cluster would become unmanageable in VMM. There’s a big clue that it’s a VMM issue. Hyper-V and Failover Clustering stay healthy. The VM’s are manageable in Hyper-V and run perfectly well.
Warning (13921)
Highly available virtual machine VM001 is not supported by VMM because one or more of its network adapters is not configured correctly.
Recommended Action
Ensure that all of the virtual network adapters are either disconnected or connected to highly available virtual networks.
I’d set up PRO earlier that afternoon. It was pretty simple. An OpsMgr console is installed on the VMM server. I installed PRO Tips on the OpsMgr 2007 SP1 server. That also sets up the VMM console and the management packs on the RMS. On the VMM server, I set up the FWDN of the OpsMgr server and the URL of the OpsMgr reporting server. That’s it!
Everything was good when I left work. When I got home I saw those above errors had taken place an VMM thought my cluster was messed up. OpsMgr alerted me about the status of the VM’s. Excellent! I checked the supplied knowledge and it was more than I’d found in a day of googling. As it turns out, my search terms sucked. The provided expertise in the alert gave me the search term I needed and I found an excellent blog post on the issue.
I use Active Directory Group Policy restricted groups to control membership of the local administrators groups. The VMM server was added by the agent install to the local administrators group to allow WMI and WinRM access. My GPO would refresh after several hours and wipe out that group membership. To fix this I reconfigured my GPO to add the VMM server to the Hyper-V host local administrators group and forced a GPO refresh on the server in question (GPUPDATE /FORCE). I restarted WinRM (and VMM agent) on the affected host. Finally I refreshed the host on the VMM server and the VM listings. Everything was back to normal in just a few seconds.
Thank you PRO!