Licensing of Hyper-V
The most painful aspect of most virtual environments is understanding the licensing
of the hypervisor, the operating systems running in the virtual machines, and the
management software. I don’t want to go into great detail about licensing in this book
because, despite new licensing agreements, special combinations of licensing still
exist through agreements with programs such as Server and Cloud Enrollment (SCE)
and the legacy Enrollment for Core Infrastructure (ECI). For most organizations, the
licensing is simple with Windows Server 2012 and above; however, changes in
Windows Server 2016 are important to understand.
One Operating System (Well Two, but Really One) with Windows
Server 2012 and 2012 R2
Prior to Windows Server 2012, numerous versions of Windows Server existed—Web,
Standard, Enterprise, and Datacenter—and each version had different capabilities and
different limits and were licensed differently. That all goes away in Windows Server
2012 and above; for medium and large companies, there are only two versions of
Windows Server: Windows Server 2012 R2 Standard and Windows Server 2012 R2
Datacenter. Both versions are exactly the same:
They have the same limits, both supporting 64 processor sockets, 640 logical
processors (320 with Hyper-V role enabled), and 4TB of memory.
Both have the same roles and features; for example, even Standard has Failover
Clustering.
They are essentially bit-for-bit the same operating system, other than that each
shows different versions in the About menu option and different background
wallpaper.
Both are licensed in two-socket increments, and all sockets in the server must be
licensed. If a server has four sockets, then two licenses of either Standard or
Datacenter must be purchased.The difference between Standard and Datacenter is in operating system environments
(OSEs), or virtual instances for each license. This is the number of virtual machines
running Windows Server that are included as part of your license: Standard allows two
virtual instances per license, and Datacenter allows unlimited instances. From a
virtualization environment perspective, this is a big difference. For each Standard
license, I can run two virtual machines running Windows Server, while with
Datacenter, I can run an unlimited number of virtual machines. Standard edition is
now targeted at physically deployed operating system instances or very light
virtualization, while Datacenter is targeted at virtualization hosts.
It is possible to stack licenses—for example, buying three Standard licenses for a
server would allow me to run six virtual machines running Windows Server (each