Microsoft Cuts Key Features From Viridian Hypervisor


Beta With Longhorn Will Lack Live Migration, Hot-Add Services


As it races to catch up to VMware and Xen rivals, Microsoft has made a tough call and decided to cut key management features out of its planned "Viridian" virtualization hypervisor for the next Windows server.

On Thursday, just days before opening its annual Windows Hardware Engineering Conference (WinHEC) in Los Angeles, the Redmond, Wash., software giant announced that it won't have live migration or hot-add resources in the first version of the hypervisor, an add-on planned to ship six months after the Windows Longhorn server ships.

Live migration, offered in the market-leading VMware and newly launched Xen-based virtualization platforms, allows customers and users to easily migrate virtual machines from one system to another system.

Hot-add capabilities, another important virtualization management feature, allows users to add or swap out storage, networking, memory and processing resources without taking down any systems.

Finally, Microsoft said it is scaling back support to a maximum of 16 cores or processors. This means Viridian can run on two-processor or four-processor servers running quad-core processors.

That news follows Microsoft's recent acknowledgement that the "Viridian" beta release would be pushed back from the first half of 2007 to the second half of the year.

The software giant said Thursday the first public beta of "Viridian" is scheduled to debut with the release-to-manufacturing of the Windows "Longhorn" Server, slated for the end of this year. This means general availability of the next Windows server will come in 2008 and "Viridian" will be available in the second half of 2008.

Microsoft also said the virtual management server being developed for Viridian, formerly code-named "carmine," and officially named System Center Virtual Machine Manager, will be available 60 to 90 days after the first beta of Viridian.

Linux rivals Red Hat and Novell are currently shipping enterprise Linux distributions with built-in Xen virtualization hypervisors. Red Hat Enterprise Linux 5.0 with Xen shipped on March 14 and the company is planning to offer enhanced virtualization support for Windows workloads in 5.1 update due in late October and 5.2 update in the first quarter of 2008.

In delivering news that likely comes as a blow to the brass at Microsoft, Mike Neil, general manager of virtualization strategy at Microsoft, said it was necessary to scale back the scope of the virtualization platform, but he assured the industry that the core capabilities enabled by the hypervisor will be delivered on time.

"We had some really tough decisions to make. We adjusted the feature set of Windows Server virtualization so that we can deliver a compelling solution for core virtualization scenarios while holding true to desired timelines," Neil wrote in his blog.

"Earlier this week we had to come to grips with some universal truths about product development," he wrote. "Shipping is a feature, too. The quality bar, the time you have, and the feature set are directly correlated. The mythical man-month -- resources are not infinite and even if you could add more it does not help get more done faster."

One ISV that is familiar with Viridian and works with most virtualization platforms said this is a big blow for Microsoft.

"They have found live migration to be harder than they
expected. They used to think they could ship without it, but now everyone has this feature they cannot launch without it. This is looking like a real disaster for Microsoft," said the ISV, who declined to be named.

"We are now in the steep part of the adoption curve and they are nowhere to be seen. They are not going to enjoy being an application running on top of a Hypervisor OS, whoever makes the hypervisor --VMware or Xen."

David Sobel, CEO of Evolve Technologies, a Fairfax, Va.-based solution provider, said live migration is one of the key benefits of virtualization.

"Microsoft not having it does open them up to competition, VMware in particular," Sobel said. "I'm disappointed this won't be available. We want to back Microsoft as the virtualization technology of choice but need them to keep up and, ideally, move ahead in terms of features."