h0bbel.p0ggel.org

As I've mentioned earlier Microsoft did a revision of licensing terms for virtual instances of Windows Server 2003 R2 Enterprise Edition and Datacenter Edition back in October. Since then my firm belief has been that this announcement could only be interpreted to be valid regardless of which virtualization vendor or technology you prefer.

While going over the VMTN Blog I found a very interesting quote from Mark Wilson which confirms that my interpretation of the licensing terms is indeed correct. Much like Mark I have also been unable to get my view 100% confirmed from "official" sources, but thanks to his posting it's clear as day.

The VMware pricing and licensing FAQ: Microsoft licensing for virtualised environments document he links to goes far in confirming this, but if you actually follow the links in VMWare document itself the answer is available directly from Microsoft too. In a whitepaper called Licensing Microsoft Server Products with Microsoft Virtual Server and Other Virtual Machine Technologies you can find the following passage under the Windows Server 2003 R2 Enterprise Edition section (page 6):

Each software license allows you to run, at any one time, one instance of the server software in a physical OS environment and up to four instances of the server software in virtual OS environments on a particular server.

That, to me at least, clearly indicates that the virtualization product of choice does not matter. It's also interesting to note the following passage from the section entitled "Run Multiple Instances of Windows Server 2003 R2 Enterprise Edition on a Server Under a Single License (page 24)"

In Figure 20, if you decide to run all five permitted instances under a license for Windows Server 2003 R2 Enterprise Edition, the instance running in the physical OS environment is restricted to running Microsoft Virtual Server or other hardware virtualization software and to running software to manage and service OS environments on server A. The illustration depicts this use. The user may not run other applications in the physical OS environment.

"Microsoft Virtual Server or other hardware virtualization software"

- There it is! One sentence that really puts it all in place, the licensing terms does not limit your choice in (hardware) virtualization vendors.

Thanks Mark for pointing me in the right direction and really looking at this again. Also, as Mark noted in his comment the Virtual Machine Technology FAQ from Microsoft really puts all discussion aside. Good one Microsoft, for once your licensing changes made IT professionals smile and not want to hide under a rock and cry!