Administrator Guide

These options are presented as checkboxes on the Create Storage Container wizard.
NOTE: Even if the Compression Allowed and Deduplication Allowed checkboxes are selected, selecting the None profile
option results in no action being taken.
You can also select the Default Data Reduction Profile, if one has been specified using the User Preferences.
After a storage administrator creates a storage container with data reduction options specified, these options are advertised (shown as
being selected) on the VM Storage Profile wizard when a VMware administrator creates a storage profile. If you edit the storage
container’s Data Reduction option, you also change the advertised capabilities that are visible in the VM Storage Profile.
For information about using VM Storage Profiles, see the VMware vCenter documentation.
Factors That Affect Data Reduction Operation
When a new virtual volume is created, it can use any Data Reduction type supported by the storage container. The preference for the
Data Reduction type on the virtual volume is influenced by either:
• The VM Storage Profile, if one is established and used
• The default Data Reduction Profile set for the storage center
The following factors affect how Data Reduction options are applied:
• If no VM Storage Policy is chosen, the Data Reduction type defaults to the value selected by the Default Data Reduction Profile.
• Editing an existing storage container’s properties to change the value of the Default Data Reduction Profile does not affect existing
virtual volumes. This change applies only to new volumes created afterward.
• If an existing volume has an enabled feature that is now disabled, the volume itself does not change. In the VM Storage Profile, the
volume would now appear to be noncompliant. To bring the volume back into compliance, you can apply a compliant policy to the
volume.
NOTE: The VM Storage Profile takes precedence when compatible storage exists.
NOTE: VM storage policies are applied only to data and config VVols and not to memory and swap VVols.
NOTE: When modifying VM storage policies especially for compression and deduplication, apply the VMware
administrator policies to all volumes associated with VM. If these same changes are not applied to all volumes, some
portion of the VM could be compressed while other portions could be uncompressed.
NOTE: The advertised capabilities only apply to VVols datastores and are not supported on legacy VMFS datastores.
NOTE: Any change to a storage container's Data Reduction profile might cause future fast cloned VMs to be created
with mismatched Data Reduction profiles for the config and data VVols. A fast clone VM shares history with the VM
from which it was created. Hence its data VVols inherit the settings of the data VVols of the original VM. There is
another side effect of this shared history — if a user applies a VM Storage Policy to the original VM, the same changes
apply to the data VVols of the fast clone VM and conversely.
NOTE: When applying a VM Storage Policy containing rules for the ScStorageProfile capability, the vCenter
administrator can ignore the datastore compatibility warning Datastore does not satisfy required
properties.. The VASA provider overrides the datastore's configured value and applies the user-provided value of
ScStorageProfile for VVols of the VM.
Expected Behaviors for Data Reduction Scenarios
The settings specified in both the storage container Data Reduction options and in the VMware Storage Profile determine the results of
VM and VVol creation. If the storage container Data Reduction settings conflict with the settings in the VM Storage Profile, creation of
VMs and virtual volumes could fail.
The following table describes the expected behavior for new VM creation with the Compression option.
Managing Virtual Volumes With Storage Manager
175