Microsoft Virtual Server 2005 R2 will not support Windows Computer Cluster Server 2003

Microsoft is preparing to launch its first high-performance computing operating system under the name of Windows Computer Cluster Server (CSS) 2003.

Company customers could evaluate this product a great platform to run virtual machines with Virtual Server 2005 R2 and are looking at it very carefully.
But they will be disappointed: System Requirements page states the product will require an x64 architecture to work. And while Virtual Server 2005 R2 supports x64 host OSes it won’t provide any support for x64 guest OSes.

So, at least until Microsoft introduces some changes with the expected Virtual Server codename vNext, there will be no way to use Windows Computer Cluster Server 2003 as a Microsoft high-performance virtualization platform.

Microsoft experts confirmed this in an official chat today:

Q: Is it possible to use virtualization software (either VMware or MS Virtual Server) to create a Virtual Server lab to develop solutions on one or 2 physical machines prior migrating to a real cluster?

A: Unfortunately the current Virtual Server product only supports 32-bit guest OS and CCS requires x64 Server.

A: The main problem is that we require x86 compatible 64 bit hardware, and 64 bit guest OS support in both VMware and MS Virtual Server is weak or not there. When there is better 64 bit guest OS it should work. But it really is an evaluation scenario – not a deployment scenario.