{HEAD ~ The boundary LBA} is stored in {TAIL ~ the memory}, the register, etc. of the disk array control device 12 
is stored in
{ HEAD ~ The boundary LBA } is stored in { TAIL ~ the memory } , the register , etc . of the disk array control device 12
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH