With Site Recovery Manager, you can connect multiple protected sites to a single recovery site. The virtual machines on the protected sites all recover to the same recovery site. This configuration is known as a shared recovery site, a many-to-one, fan-in, or an N:1 configuration.

In the standard one-to-one Site Recovery Manager configuration, you use Site Recovery Manager to protect a specific instance of vCenter Server by pairing it with another vCenter Server instance. The first vCenter Server instance, the protected site, recovers virtual machines to the second vCenter Server instance, the recovery site.

Another example is to have multiple protected sites that you configure to recover to a single, shared recovery site. For example, an organization can provide a single recovery site with which multiple protected sites for remote field offices can connect. Another example for a shared recovery site is for a service provider that offers business continuity services to multiple customers.

In a shared recovery site configuration, you install one Site Recovery Manager Server instance on each protected site, each of which connects to a different vCenter Server instance. On the recovery site, you install multiple Site Recovery Manager Server instances to pair with each Site Recovery Manager Server instance on the protected sites. All of the Site Recovery Manager Server instances on the shared recovery site connect to a single vCenter Server instance. Each Site Recovery Manager Server instance in a pair must have the same Site Recovery Manager extension ID, which you can set when you install Site Recovery Manager Server. You can consider the owner of a Site Recovery Manager Server pair to be a customer of the shared recovery site.

You can convert an existing one-to-one configuration of Site Recovery Manager into a shared recovery site configuration. To convert a one-to-one configuration to a shared recovery site configuration, you deploy additional Site Recovery Manager Server and vCenter Server instances as protected sites, and pair them with additional Site Recovery Manager Server instances that all connect to the existing vCenter Server instance on the recovery site. Each pair of Site Recovery Manager Server instances in the shared recovery site configuration must use a different Site Recovery Manager extension ID. For example, if you installed a one-to-one configuration that uses the default Site Recovery Manager extension ID, you must deploy all subsequent Site Recovery Manager Server pairs with different custom extension IDs.

You can use either array-based replication or vSphere Replication or a combination of both when you configure Site Recovery Manager Server to use a shared recovery site.

In addition to the shared recovery site configuration, Site Recovery Manager also allows and supports shared protected site (one-to-many, fan-out, or 1:N) and many-to-many (N:N) configurations.

An organization has two field offices and a head office. Each of the field offices is a protected site. The head office acts as the recovery site for both of the field offices. Each field office has a Site Recovery Manager Server instance and a vCenter Server instance. The head office has two Site Recovery Manager Server instances, each of which is paired with a Site Recovery Manager Server instance in one of the field offices. Both of the Site Recovery Manager Server instances at the head office extend a single vCenter Server instance.

Field office 1

Site Recovery Manager Server A

vCenter Server A

Field office 2

Site Recovery Manager Server B

vCenter Server B

Head office

Site Recovery Manager Server C, that is paired with Site Recovery Manager Server A

Site Recovery Manager Server D, that is paired with Site Recovery Manager Server B

vCenter Server C, that is extended by Site Recovery Manager Server C and Site Recovery Manager Server D

Example of Using Site Recovery Manager in a Shared Recovery Site Configuration
Architecture of SRM in a Shared Recovery Site Configuration