CMMVC9176E: The pool specified is a data reduction pool. For volumes or volume copies which are thin
provisioned or compressed and created from a data reduction pool, the volume cannot have a cache
mode of none or readonly.
Explanation
A thin-provisioned or compressed volume or volume copy that you create from a data reduction pool
must have a cache mode of readwrite.
User Response
Change the cache mode on the volume to readwrite and retry the command.