What caching policy is assigned if VMDKs for a VM are in different Datastores?
Caching policy assigned to all VMDKs of a VM is the caching policy assigned to the VM, and all the VM’s VMDKs get assigned the same cache policy under all conditions. In other words, two different VMDKs of a VM cannot have two different caching policies.
If you have applied cache policy at the Datastore level and not at the VM level, and if you have multiple VMDKs in a VM, then the cache policy assigned to the VM (and all its VMDKs) will be the cache policy of the Datastore where the VM’s .vmx file (VM’s configuration file) resides.
To change this policy for the VM (and all its VMDKs), you can do one of these three things:
1. In VirtuCache, apply cache policy at the VM level, which will override Datastore level cache policy for the VM, and all its VMDKs.
2. You can storage vMotion the VM to the Datastore whose cache policy you want applied to the VM.
3. If you don’t have a VMware license for storage vMotion, shutdown the VM and migrate it to the Datastore whose cache policy you want applied to the VM.