The Virtual Machine Management Service (VMMS) runs in user mode in the management OS of every Hyper-V host. It has nothing to do with SCVMM; that’s just an unfortunate similarity in names. The VMMS provides the WMI or management interface to Hyper-V for all management tools, such as PowerShell, Hyper-V Manager, or Failover Cluster Manager.
Microsoft published a KB article for when a standard Hyper-V replica is created unexpectedly after you restart the VMMS service in Windows Server 2012.
Consider the following scenario:
- You have Windows Server 2012-based Hyper-V servers that are running in an environment that has Hyper Replica deployed.
- You set more than two recovery points.
- You restart the VMMS service on a replica server, or you restart the replica server.
- You wait about 5 minutes until the first time delta is arrived from the primary site.
In this scenario, a standard replica (recovery point) is created unexpectedly.
Note If the time interval between the latest recovery point and the arrival of the delta is less than 60 minutes, a standard replica should not be created.
This issue occurs because the VMMS service incorrectly compares the time stamp of the earliest recovery point to the latest delta time stamp. Therefore, the system takes a new snapshot every time the VMMS service is restarted
A hotfix has been published to resolve this issue. It’s not an issue I’d expect to see too often but the fix is there.