Hardware Controller Grow RAID Unit
Grows the underlying hardware RAID unit (aka array) to a new larger size. RAID controllers will do a full re-layout of the data which can impact performance until it completes. Once the re-layout is done you can then do a Storage Pool Expand to expand the storage pool to use the additional disk space.
Navigation: Storage Management --> Physical Disks --> (target RAID unit) --> Grow (rightclick)