6.2

Table Of Contents
A storage reservation policy is a tag applied to one or more datastores by a fabric administrator and is
used to group datastores that have similar characteristics, such as speed or price. A datastore can be
assigned to only one storage reservation policy at a time, but a storage reservation policy can have many
different datastores. A fabric administrator creates a storage reservation policy and assigns it to one or
more datastores. A tenant administrator or business group manager then assigns the storage reservation
policy to a volume in a virtual blueprint. When a user requests a virtual machine that uses the blueprint,
the storage reservation policy specified in the blueprint is used to select a datastore for the machine’s
volume.
When you add or edit a volume in a virtual blueprint, you can make the following assignments:
n
Assign a single datastore to the volume. This one-to-one relationship assigns only the specified
datastore at provisioning time. If the datastore is not available or lacks sufficient space, provisioning
fails.
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Assign a storage reservation policy to the volume. This assignment allows the selection of one of the
datastores associated with the storage reservation policy at provisioning time. If the policy’s
datastores are unavailable or lack sufficient space, provisioning fails.
n
Assign a storage reservation policy to the volume and include the custom property
VirtualMachine.DiskN.StorageReservationPolicyMode with the value of NonExact. This
configuration allows you to assign a datastore that is not included in the storage reservation policy.
n
Do not assign a datastore or a storage reservation policy to a volume. Not making an assignment
allows selection from all available datastores at provisioning time. Provisioning fails if a datastore with
sufficient space is not available.
Datastore priority, as assigned by a datastore reservation, is also used to select a datastore at
provisioning time.
Avoid specifying a storage path and a storage reservation policy for the same volume. If you must specify
a storage path and a storage reservation policy for the same volume, the storage path takes precedence
over the storage reservation policy.
Choosing a Storage Scenario
When creating vSphere, KVM (RHEV), or SCVMM Create, Clone, FlexClone, or Linked Clone blueprints,
tenant administrators and business group managers can assign datastores to volumes, or assign storage
reservation policies to volumes.
Depending on the type of blueprint you are working with and your storage needs, the procedure to assign
datastores to volumes differs slightly.
IaaS Configuration for Virtual Platforms
VMware, Inc. 159