Certain ones of a plurality of SAS hard disk drives are assigned to different SAS zones using a SAS zoning expander(s). A processor and SAS RAID controller have access to only those SAS hard disk drives assigned to the same zone(s) as the processor and SAS RAID controller. Each SAS RAID controller determines when a RAID hard disk drive in its zone fails, and then notifies the RAID hard disk drive failure to a service enclosure processor (SEP) of the SAS zoning expander. The SEP re-allocates an available hot-spare hard disk drive to the zone of the failed RAID hard disk drive. When the SAS RAID controller detects that a functional hard disk drive is now available in its zone, the RAID image is rebuilt using the zone reassigned hot-spare hard disk drive that then becomes one of the RAID hard disk drives of that zone.