designating anyone of {HEAD ~ the plurality} of {TAIL ~ storage} arrays as a primary device of the CSA 
of
designating anyone of { HEAD ~ the plurality } of { TAIL ~ storage } arrays as a primary device of the CSA
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH