Whether or not mainstream IT shops will care is another matter. Many IT managers, even those who are not yet using virtualization technology, may already believe that buying software from market leader VMware Inc. is a better long-term bet.
And it still remains to be seen whether Microsoft will suffer in the market for Viridian's lateness because customers will still be buying Windows to run on VMware virtual machines anyway.
"If Microsoft is pulling features, it just puts them farther behind," said Steve Iltis, a networking administrator at Metal Exchange Corp., St. Louis. His company is not using virtualization technology today but may consider it soon for disaster recovery applications.
When Iltis is ready to buy, however, he said he will reevaluate tools from both Microsoft and VMware. Although Microsoft lags today, by the time he is ready, the competitive scene may have shifted, he said.
Viridian live migration, hot-add features postponed
The most recent round of questions about Microsoft's inability to deliver began earlier this month when Mike Neil, general manager of virtualization at Microsoft said on the Windows Server team blog that the company would postpone several features from Viridian.
Those include live migration and hot-add resources for storage, networking, memory and processor to a future hypervisor release. Microsoft also limited the number of cores/logical processors supported to 16.
Dave Chacon, an information services technology manager at Ping Inc. based in Phoenix, said he would have preferred that Microsoft include all of the features originally planned, particularly the live migration capability. But, for the most part, Chacon said he cares mainly about the features related to performance tuning, and those remain.
"The idea of running off of a hypervisor layer instead of a full OS is what I need most," said Chacon, who uses Microsoft's Visual Server 2005 for test and development.
Like Iltis, Chacon keeps his eye on the market and said he will consider all options as his company moves forward. VMware's main product, ESX Server, does not compete directly with Microsoft's currently available virtualization software, Virtual Server 2005, either in performance or on price.
Virtual Server 2005 R2 is available as a free download, and ESX, which is for higher end applications, can cost thousands. Viridian will eventually become part of Windows. "At some point we need to determine whether or not we will want to pay for a product," Chacon said.
Virtualization's two biggest challenges
One of the toughest challenges IT shops face today regarding virtualized environments has to do with management of virtual machines, said Neil Macehiter, a principal at Macehiter Ward-Dutton, a consulting firm in Cambridge, U.K. There is a growing management problem with virtual machines and instances in terms of what there is physically and where they are virtually.
Licensing is another significant challenge because, historically, it was predicated around physical machines. Microsoft has taken some initial steps to alter its licensing so that it addresses virtualization. In October 2005, Microsoft said it would offer customers using Windows Server 2003 Enterprise Edition up to four virtual instances at no extra cost.
In February, the company said that its SQL Server Enterprise Edition customers have to buy only one license per physical processor regardless of the number of virtually deployed instances.
Microsoft's primary competitor continues to be VMware. Gordon Haff, an analyst at Nashua, N.H.-based consulting firm Illuminata, said that while he sees why Microsoft would like to see customers with an all-Microsoft stack, in the end the company makes a lot of money running its software on top of VMware.
It is not as if the only other virtualization technology available ran only on Linux, said Haff. Customers will be using VMware or Virtual Iron, for example, and they will buy Windows and other Microsoft software to run on those virtual machines.
"Maybe Microsoft should just step back and partner with VMware rather than fighting them so intensely," Haff said.