How VMware Live Site Recovery Interacts with DPM and DRS During Recovery

Distributed Power Management (DPM) and Distributed Resource Scheduler (DRS) are not mandatory, but VMware Live Site Recovery supports both services and enabling them provides certain benefits when you use VMware Live Site Recovery.

DPM is a VMware feature that manages power consumption by ESX hosts. DRS is a VMware facility that manages the assignment of virtual machines to ESX hosts.

VMware Live Site Recovery temporarily deactivates DPM for the clusters on the recovery site and ensures that all hosts in the cluster are powered on when recovery or test recovery starts. This allows for sufficient host capacity while recovering virtual machines. After the recovery or test is finished, VMware Live Site Recovery restores the DPM settings on the cluster on the recovery site to their original values.

For planned migration and reprotect operations, VMware Live Site Recovery also deactivates DPM on the affected clusters on the protected site and ensures that all of the hosts in the cluster are powered on. This allows VMware Live Site Recovery to complete host level operations, for example unmounting datastores or cleaning up storage after a reprotect operation. After the planned migration or reprotect operation has finished, VMware Live Site Recovery restores the DPM settings on the cluster on the protected site to their original values.

The hosts in the cluster are left in the running state so that DPM can power them down as needed. VMware Live Site Recovery registers virtual machines across the available ESX hosts in a round-robin order, to distribute the potential load as evenly as possible. VMware Live Site Recovery always uses DRS placement to balance the load intelligently across hosts before it powers on recovered virtual machines on the recovery site, even if DRS is deactivated on the cluster.

If DRS is enabled and in fully automatic mode, DRS might move other virtual machines to further balance the load across the cluster while VMware Live Site Recovery is powering on the recovered virtual machines. DRS continues to balance all virtual machines across the cluster after VMware Live Site Recovery has powered on the recovered virtual machines.