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Protected Sites and Recovery Sites
In a typical SRM installation, the protected site provides business-critical datacenter services. The recovery site
is an alternative facility to which these services can be migrated.
The protected site can be any site where vCenter supports a critical business need. The recovery site can be
located thousands of miles away. Conversely, the recovery site can be in the same room as a way of establishing
redundancy. The recovery site is usually located in a facility that is unlikely to be affected by environmental,
infrastructure, or other disturbances that affect the protected site.
SRM has the following requirements for the VMware vSphere
®
configurations at each site:
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Each site must have at least one datacenter.
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If you are using array-based replication, identical replication technologies must be available at both sites.
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The recovery site must have hardware, network, and storage resources that can support the same virtual
machines and workloads as the protected site.
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The sites should be connected by a reliable IP network. If you are using array-based replication, ensure
your network connectivity meets the arrays' network requirements.
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The recovery site should have access to comparable networks (public and private) as the protected site,
although not necessarily the same range of network addresses.
Site Pairing
The protected and recovery sites must be paired before you can use SRM. SRM includes a wizard that guides
you through the site-pairing process. You must establish a connection between the sites and you must provide
authentication information for the two sites so they can exchange information. Site pairing requires vSphere
administrative privileges at both sites. To initiate the site-pairing process, you must know the user name and
password of a vSphere administrator at each site. If you are using vSphere Replication, pair vSphere Replication
Management Servers similarly to how SRM sites are paired.
Array-Based Replication
When using array-based replication, one or more storage arrays at the protected site replicate data to peer
arrays at the recovery site. Storage replication adapters (SRAs) enable integration of SRM with a wide variety
of arrays.
If you plan to use array-based replication with SRM, establish replication before you install and configure SRM.
Storage Replication Adapters
Storage replication adapters are not part of an SRM release. They are developed and supported by your array
vendor. You can download storage replication adapters and their documentation from
http://www.vmware.com/download/srm/. VMware does not support storage replication adapters
downloaded from other sites. You must install an SRA specific to each array that you use with SRM on the
SRM server host. SRM supports using multiple SRAs.
About Bidirectional Operation
You can use a single set of paired SRM sites to protect in both directions. Each site can simultaneously be both
a protected site and recovery site but for a different set of virtual machines. This feature is not limited to array-
based replication but when you are using array-based replication, any given one of the array’s LUNs is only
ever replicating in one direction. Two different LUNs in the same array can each be replicating in different
directions from each other.
Chapter 1 Administering VMware vCenter Site Recovery Manager
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