I noticed this weekend that one host in a Windows 2012 Failover Cluster showed «host not responding» in the statuswindo in VMM 2012. The VMs running on the host worked just fine and we could managed the VMs through both Hyper-V manager and Failover Cluster msc.
The event viewer on the host showed error 3001 very often (every half min. or even more often).
This error has to do something with WMI so I guess this had to do with the Performance Counter not giving the info to VMM.
I came over a nice blog (please send me the link again for reference!) which showed me how to reset the performance counter
open an eleveted cmd.exe promot and go to c:windowssyswow64
There you can run the following command (you must have navigated to the c:windowssyswo64 directory or else you will get an error with error code 2 saying you can’t restore from a system restore backup)
After that you must run the following command to sync the information, important!