5.5

To configure array-based replication, you must assign each virtual machine to a resource pool, folder, and
network that exist at the recovery site. You can specify defaults for these assignments by selecting inventory
mappings. SRM applies inventory mappings when you create the protection group. If you do not specify
inventory mappings, you must configure them individually for each member of the protection group. SRM
does not protect virtual machines that you did not configure or that you incorrectly configured for
replication, even if they reside on a protected datastore.
If your storage array supports consistency groups, SRM is compatible with vSphere Storage DRS and
vSphere Storage vMotion. You can use Storage DRS and Storage vMotion to move virtual machine files
within a consistency group that SRM protects. If your storage array does not support consistency groups,
you cannot use Storage DRS and Storage vMotion in combination with SRM.
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How SRM Computes Datastore Groups on page 30
SRM determines the composition of a datastore group by the set of virtual machines that have files on
the datastores in the group, and by the devices on which those datastores are stored.
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Create Array-Based Protection Groups on page 31
You create array-based protection groups to enable the protection of virtual machines in datastore
groups that you configure to use array-based replication.
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Edit Array-Based Protection Groups on page 32
You can change the name and description of an array-based protection group and add or remove
datastore groups that are part of the protection group.
How SRM Computes Datastore Groups
SRM determines the composition of a datastore group by the set of virtual machines that have files on the
datastores in the group, and by the devices on which those datastores are stored.
When you use array-based replication, each storage array supports a set of replicated datastores. On storage
area network (SAN) arrays that use connection protocols such as Fibre Channel and iSCSI, these datastores
are called logical storage units (LUN) and are composed of one or more physical datastores. On network file
system (NFS) arrays, the replicated datastores are typically referred to as volumes. In every pair of
replicated storage devices, one datastore is the replication source and the other is the replication target. Data
written to the source datastore is replicated to the target datastore on a schedule controlled by the
replication software of the array. When you configure SRM to work with an SRA, the replication source is at
the protected site and the replication target is at the recovery site.
A datastore provides storage for virtual machine files. By hiding the details of physical storage devices,
datastores simplify the allocation of storage capacity and provide a uniform model for meeting the storage
needs of virtual machines. Because any datastore can span multiple devices, SRM must ensure that all
devices backing the datastore are replicated before it can protect the virtual machines that use that datastore.
SRM must ensure that all datastores containing protected virtual machine files are replicated. During a
recovery or test, SRM must handle all such datastores together.
To achieve this goal, SRM aggregates datastores into datastore groups to accommodate virtual machines
that span multiple datastores. SRM regularly checks that datastore groups contain all necessary datastores
to provide protection for the appropriate virtual machines. When necessary, SRM recalculates datastore
groups. For example, this can occur when you add new devices to a virtual machine, and you store those
devices on a datastore that was not previously a part of the datastore group.
A datastore group consists of the smallest set of datastores required to ensure that if any of a virtual
machine's files is stored on a datastore in the group, all of the virtual machine's files are stored on datastores
that are part of the same group. For example, if a virtual machine has disks on two different datastores, then
SRM combines both datastores into a datastore group. SRM also combines devices into datastore groups
according to set criteria.
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A virtual machine has files on two different datastores.
Site Recovery Manager Administration
30 VMware, Inc.