You can enable deduplication and compression by editing configuration parameters on an existing Virtual SAN cluster.
- Navigate to the Virtual SAN host cluster in the vSphere Web Client.
- Click the Configure tab.
- Under Virtual SAN, select General.
- In the Virtual SAN is turned ON pane, click the Edit button.
- Configure deduplication and compression.
- Set the disk claiming mode to Manual.
- Set deduplication and compression to Enabled.
- (Optional) : Enable reduced redundancy for your VMs.
Click OK to save your configuration changes.
While enabling deduplication and compression, Virtual SAN changes disk format on each disk group of the cluster. To accomplish this change, Virtual SAN evacuates data from the disk group, removes the disk group, and recreates it with a new format that supports deduplication and compression.
The enablement operation does not require virtual machine migration or DRS. The time required for this operation depends on the number of hosts in the cluster and amount of data. You can monitor the progress on the Tasks and Events tab.