To change the disk type for a VM, the virtual datacenter must be assigned multiple disk tiers. For example, an 80% reservation pool may have both Tier 1 and Tier 2 disks available.
VMs can be migrated live between disk tiers. Multiple disk tiers can be associated with a single pool type.
Follow these these steps to migrate to a different disk tier.
1. From the Virtual Machines tab, locate the VM required and click Details.
2. The VM details will display. In the General section, select Edit and change the Storage Policy tier as appropriate. Click Save.
3. In the Hardware section, select Hard Disks > Edit.
4. Select VM Default Policy to change the tier as appropriate. Click Save.
5. Migration may take some time, depending on the disk size. You can check the status in the Recent Tasks bar at the bottom of your screen.