Add a VMDK Anti-Affinity Rule

Create a VMDK anti-affinity rule to place and keep certain virtual hard disks of a virtual machine on different datastores within the datastore cluster.

When you create an anti-affinity rule, it applies to those of the virtual machine's hard disks that are on datastores within the selected datastore cluster. Anti-affinity Storage DRS rules operate during migrations that Storage DRS initiates or recommends, but they do not operate when the user initiates a migration.

Prerequisites

Procedure

1. Navigate to a virtual machine in the inventory.
2. On the Configure tab, expand Settings and click VM SDRS Rules.
3. Click the Add button.
   The Add SDRS rule dialog box opens.
4. From the Type drop-down menu, select VMDK anti-affinity.
5. In the Rule name text box, enter a name for the rule.
6. From the Datastore cluster drop-down menu, select the datastore cluster where the anti-affinity rule will operate.
   All virtual hard disks that are placed on datastores within the selected datastore cluster appear at the bottom of the dialog box.
7. Select the virtual hard disks to which the anti-affinity rule applies.
8. (Optional) Deselect the Enable the rule check box.
   Deselecting the Enable the rule check box deactivates the rule. You can still create the rule, but after creation the rule is not applied to the selected virtual hard disks.
9. Click OK.

Results

A VMDK anti-affinity rule is created. If the rule is enabled, all selected virtual hard disks are placed and kept on different datastores within the datastore cluster.