{HEAD ~ Machine manager} 610 also keeps {TAIL ~ track} of the specific versions of software that is being used on each of the machines as well as the Virtual Machine Images that are installed on each of the machines 
keeps
{ HEAD ~ Machine manager } 610 also keeps { TAIL ~ track } of the specific versions of software that is being used on each of the machines as well as the Virtual Machine Images that are installed on each of the machines
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH