System information

How Changes to vCenter Server Inventory Affect Site Recovery Manager
Because Site Recovery Manager protection groups apply to a subset of the vCenter Server inventory,
changes to the protected inventory made by vCenter Server administrators and users can affect the integrity
of Site Recovery Manager protection and recovery. Site Recovery Manager depends on the availability of
certain objects, such as virtual machines, folders, resource pools, and networks, in the vCenter Server
inventory at the protected and recovery sites. Deletion of resources such as folders or networks that are
referenced by recovery plans can invalidate the plan. Renaming or relocating objects in the vCenter Server
inventory does not affect Site Recovery Manager, unless it causes resources to become inaccessible during
test or recovery.
Site Recovery Manager can tolerate certain changes at the protected site without disruption.
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Deleting protected virtual machines.
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Deleting an object for which an inventory mapping exists.
Site Recovery Manager can tolerate certain changes at the recovery site without disruption.
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Moving placeholder virtual machines to a different folder or resource pool.
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Deleting an object for which an inventory map exists.
Site Recovery Manager and the vCenter Server Database
If you update the vCenter Server installation that Site Recovery Manager extends, do not reinitialize the
vCenter Server database during the update. Site Recovery Manager stores identification information about
all vCenter Server objects in the Site Recovery Manager database. If you reinitialize the vCenter Server
database, the identification data that Site Recovery Manager has stored no longer matches identification
information in the new vCenter Server instance and objects are not found.
How Site Recovery Manager Interacts with DPM and DRS During
Recovery
Distributed Power Management (DPM) and Distributed Resource Scheduler (DRS) are not mandatory, but
Site Recovery Manager supports both services and enabling them provides certain benefits when you use
Site Recovery Manager.
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.
Site Recovery Manager temporarily disables 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, Site Recovery Manager
restores the DPM settings on the cluster on the recovery site to their original values.
For planned migration and reprotect operations, Site Recovery Manager also disables DPM on the affected
clusters on the protected site and ensures that all of the hosts in the cluster are powered on. This allows
Site Recovery Manager 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,
Site Recovery Manager 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.
Site Recovery Manager registers virtual machines across the available ESX hosts in a round-robin order, to
distribute the potential load as evenly as possible. Site Recovery Manager 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 disabled on the cluster.
Site Recovery Manager Administration
92 VMware, Inc.