For example, {TAIL ~ web servers} continue to request operations on {HEAD ~ the database} while content is being moved 
For example , { TAIL ~ web servers } continue to request operations on { HEAD ~ the database } while content is being moved
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH