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6 Disaster Recovery with Dell PS Series SANs and VMware vSphere Site Recovery Manager | TR1073
2 VMware SRM terminology
VMware SRM has unique terms when discussing DR planning and configuration. Because both SRM and the
PS Series storage support bi-directional replication and configuration, it is not sufficient to use the terms
production site and DR site. For example, consider a company with a virtual environment in New York running
Virtual Machines (VMs) in production that is replicating to Chicago as a DR site. Chicago also has its own
virtual environment in production and its DR site is in New York. With SRM and bi-directional replication
provided by the storage, each site is protected from a disaster. If there is a problem in New York, all of the
virtual machines previously hosted there can be recovered in Chicago and brought online. The reverse holds
true if there is a problem in Chicago. Another example would be an environment that leverages the many-to-
one replication of the PS Series array, where multiple satellite offices are each configured to replicate back to
a centralized corporate datacenter.
To avoid confusion, VMware uses the terms protected site and recovery site to differentiate between the two
sites for a VM. A protected site is the site in which production VMs are up and running. These VMs must be
protected by configuring array-based replication for their datastores to another site.
A recovery site is the site that the protected VMs are replicated to. In the case of a disaster, SRM can bring
these VMs online following a clear plan, minimizing the downtime and recovery time.