Machine manager 610 knows a location of each rack within the networks and each machine and {HEAD ~ the database} that is/are located within {TAIL ~ the rack} 
is located within
Machine manager 610 knows a location of each rack within the networks and each machine and { HEAD ~ the database } that is / are located within { TAIL ~ the rack }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL