License

do require license using server 2012 r2 standard edition or other edition (old or new) vm in physical machine os server 2012 r2 datacentre (licensed).

the short answer question no. when run 2012 r2 dce (data center edition) on host, can have unlimited server os guests. if use client os on vm windows 7 or 8, need licensed separately. 

• windows server os licensing per socket. so, if run windows server os on physical machine 2 sockets need 1x license of windows server 2012 r2 standard or data center editions. similarly, if run windows server os on physical machine 4 sockets need 2x license of windows server 2012 r2 standard or data center editions. regardless of number of cores, or hyper-threading. 
• windows server 2012 r2 standard grants 2 server os licenses vms. data center edition grants unlimited server os licenses. magic number 10 vms. if plan on running 10 or more vms on host, data center edition makes economical sense. 
• clustering , vm mobility: you're required have sufficient licenses maximum number of vms ever reside on host contiguous 90 day period. so, in failover cluster situation example, if host ends 20 vms @ point in time, needs licensed many. if you're using dce, not issue.

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sam boutros, senior consultant, software logic, kop, pa http://superwidgets.wordpress.com (please take moment vote helpful and/or mark answer, applicable) _________________________________________________________________________________ powershell: learn before it's emergency http://technet.microsoft.com/en-us/scriptcenter/powershell.aspx http://technet.microsoft.com/en-us/scriptcenter/dd793612.aspx

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