Microsoft's virtual server ruffles feathers

Microsoft this week is scheduled to take its first step into server virtualization with the release of Virtual Server 2005, but the company will face a rash of technological, licensing and support challenges before it can claim success.

Corporate users are aware that Virtual Server 2005, which lets multiple operating systems run on a single physical machine, is heavily Windows-centric and lacks the performance capabilities and feature set of other virtualization architectures.

In addition, Microsoft's software licensing has not been altered to accommodate virtualization - leaving users with savings on hardware when consolidating servers but not on software.

Also questions are arising about Microsoft's plan to support Windows operating systems when they are running on Virtual Server 2005 but to deny support when those same operating systems run on another vendor's virtual machine technology.

"One of our concerns is the Microsoft product will be very Microsoft-specific," says Allan Campbell, director of IT architecture for MassMutual Financial Group in Springfield, Mass. "We are looking at Linux and we want our virtualization strategy to support that, and so we are concerned about Microsoft's real commitment to supporting Linux on their virtual platform."

Virtual Server 2005, which requires Windows Server 2003 as the "host" operating system under Virtual Server, supports Linux as a "guest" operating system running inside a virtual machine, but Windows NT and 2000 are the featured guest operating systems.

"There are optimizations that we will do to make sure that Windows performs the best in that guest environment so that we can actually tune it for a virtual machine environment," says Eric Berg, group product manager for Windows Server. "And you can expect to see slower performance on those operating systems that are not tuned for that environment."

That deference to Windows, in part, is why Campbell is using VMWare's ESX virtualization platform to consolidate roughly 80 Windows servers onto four eight-way IBM servers. Microsoft's support policy is the reason Campbell almost exclusively uses those virtual machines for testing and development, and not in production.

"VMWare is not an officially supported platform for Microsoft," Campbell says. "If we have a problem with the Windows software they don't have to give us support unless we can recreate the problem on a physical server."

The support issue is different with Virtual Server 2005 - Microsoft will support versions of Windows that run on virtual machines, according to Microsoft's Berg.

Campbell says he is pleased Microsoft is taking virtualization seriously but that the company will have to answer licensing and support questions.

Microsoft has not altered its licensing and the company says it doesn't plan to do so in the near future, leaving users to pay for each server within each virtual machine.