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