Storage Pool Recover

If you are using hardware RAID then you will mark hot-spare disks in the 'Hardware Enclosures & Controllers' section. This is the most common way of managing spare disk drives but you can also designate spares at the software RAID level using this dialog if you're using software RAID5/6/10/Z/Z2.
Navigation: Storage Management --> Storage Pools --> Storage Pool --> Recover (toolbar)