a management information recording device for recording information concerning {HEAD ~ each logical unit} and information concerning disk units corresponding to {TAIL ~ each logical unit} in association with each other 
a management information recording device for recording information concerning { HEAD ~ each logical unit } and information concerning disk units corresponding to { TAIL ~ each logical unit } in association with each other
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH