You can install Site Recovery Manager in any of the deployment models that vCenter Server supports. However, the vCenter Server deployment model that you select can have implications for Site Recovery Manager operation.
You deploy vCenter Server with a Platform Services Controller. You can either embed the Platform Services Controller with vCenter Server or it can be external to vCenter Server. Several vCenter Server instances can share the same external Platform Services Controller.
You can deploy the Platform Services Controller in several different configurations.
Each Platform Services Controller can have its own vCenter Single Sign-On domain.
Several Platform Services Controller instances can join the same vCenter Single Sign-On domain.
You can configure vCenter Single Sign-On domains in Enhanced Linked Mode, which federates all of the Platform Services Controller instances from each of the linked domains.
For information about the deployment models that vCenter Server supports, see vCenter Server Deployment Models in vSphere Installation and Setup.
You must take the deployment model of vCenter Server and Platform Services Controller into consideration when you install Site Recovery Manager. During a disaster recovery, Site Recovery Manager, vCenter Server, and the associated Platform Services Controller must be up and running on the recovery site.
Configuring the Platform Services Controller and Selecting the Correct vCenter Server Instance in an Enhanced Linked Mode Environment
When you install Site Recovery Manager Server, you provide the address of the Platform Services Controller that is associated with the vCenter Server instance to protect. You then select the vCenter Server instance with which to register Site Recovery Manager from the list of all of the vCenter Server instances that this Platform Services Controller serves. In an Enhanced Linked Mode environment, that list might include vCenter Server instances from other sites. If you select the wrong vCenter Server instance and complete the Site Recovery Manager installation, you cannot subsequently modify the Site Recovery Manager installation to select the correct vCenter Server instance. In this case, you must uninstall and reinstall Site Recovery Manager to select the correct vCenter Server instance.
When you install Site Recovery Manager Server on the protected site, make sure that you select the vCenter Server instance that manages the virtual machines to protect.
When you install Site Recovery Manager Server on the recovery site, make sure that you select the vCenter Server instance to which to recover virtual machines.
Ensure that the Platform Services Controller, vCenter Server, and Site Recovery Manager Server are all located on the protected site, or all on the recovery site.
After you have installed Site Recovery Manager, if vCenter Server migrates to a different Platform Services Controller or if the address of the Platform Services Controller changes, you can reconfigure Site Recovery Manager with the new Platform Services Controller address. For example, you can change from an embedded Platform Services Controller to an external Platform Services Controller. For information about changing Platform Services Controller, see Reconfigure vCenter Server with Embedded Platform Services Controller to vCenter Server with External Platform Services Controller in vSphere Installation and Setup.
You change the Platform Services Controller address by running the Site Recovery Manager installer in Modify mode.
Sharing Platform Services Controller Instances Across Site Recovery Manager Sites
A single point of failure is created if you share a Platform Services Controller instance between the protected and recovery sites. If the shared Platform Services Controller goes offline, neither the protected site nor the recovery site will function, making recovery impossible.
Concurrent Installations of Site Recovery Manager in an Enhanced Linked Mode Environment
In an Enhanced Linked Mode environment, do not install Site Recovery Manager under more than one Platform Services Controller at the same time. A conflict can arise in the creation of the solution user that Platform Services Controller creates at the domain level for Site Recovery Manager authentication with vCenter Server if the following conditions exist:
If the installation of one Site Recovery Manager Server instance overlaps with the installation of another Site Recovery Manager Server instance under two different Platform Services Controller instances.
Those Platform Services Controller instances are in Enhanced Linked Mode.
The conflict does not prevent installation, but it does cause one of the Site Recovery Manager Server instances to fail to start, with the error message Failed to start service. The message Failed to start Authorization Manager appears in the event log for that Site Recovery Manager Server instance.