In SCVMM, you can configure maintenance mode for a virtual machine host anytime that you need to perform maintenance tasks on the physical host, such as applying security updates or replacing hardware on the physical host computer.

Before maintaining a host that is being used for recovery, edit VPGs that contain virtual machines that are replicating to this host and change their recovery host. Assuming that you only change the recovery host, the resulting update uses live migration and should be very quick.