Over the past year, Microsoft has made some virtualization-friendly changes to its licensing policy, but restrictions on virtual machine mobility for nonvolume license holders and operating systems remain an issue for server virtualization users.
"[Microsoft's] virtualization licensing is not friendly to customers, and the constraints are very serious," said Paul DeGroot, a licensing analyst at Kirkland, Wash.-based Directions on Microsoft.
Microsoft's licensing policy ties licenses to physical servers, restricting virtual machine (VM) mobility, which poses a problem for VMware and Citrix Systems Inc. XenServer users using live migration capabilities -- which its own virtualization technology, Hyper-V, won't have until version R2 ships later next month.A more licensing-friendly Microsoft?
The restrictive policy comes as no surprise. Microsoft's licensing policies typically reflect its own capabilities rather than those of the third-party products Microsoft customers use, DeGroot said.
"Microsoft's licensing will always be behind, because if a third party product has a capability that they don't, they won't license in a friendly way for that capability - even if Microsoft customers want to be able to use it."
And the lack of licensing-friendly policies begs a question: When Hyper-V R2 with Live Migration ships toward the end of next month, will Microsoft remove live migration restrictions in all its licensing policies?
DeGroot said it is a possibility, but Microsoft has not hinted at any change.
Still, the company has rewarded its big-spending customers with some virtualization-friendly policy changes. Last September, Microsoft waived its 90-day reassignment rule for volume license holders, letting them reassign virtualized Microsoft applications from one server to another within a server farm as frequently as needed. But nonvolume license holders -- which are mostly small and medium-sized businesses -- are still beholden to the reassignment rule, and the 90-day rule still applies to Windows Server operating systems, Client Access Licenses and Management Licenses. The restriction also remains for customers with original equipment manufacturer (OEM) agreements and Full Packaged Product (FPP) channels.
So those customers either have to upgrade to a volume license or deal with these restrictions.
Hurdles to dynamic data centers and cloud computing
Microsoft's licensing policies also stand in the way of moving toward a dynamic data center -- not to mention moving to shared tenancy model of cloud computing. The reassignment rule, for example, is easy to violate accidentally, DeGroot said.
"You might want to run an automated data center with rules like 'Move a VM when the CPU hits 90%,' but that move may violate the 90-day rule, and the software doesn't know that," DeGroot said. "Then IT guys are alerted of a problem and have to research the issue, which defeats the purpose of building a dynamic data center."
And while mobility restrictions for Microsoft's major server applications (Exchange, SQL, and SharePoint) have already been lifted, the restrictions remain in place for each application's underlying server OS, said Burton Group analyst Chris Wolf, who hosted a session on virtualization licensing at VMworld 2009 in San Francisco earlier this month.
Wolf said one of the most important changes Microsoft needs to make is to remove the mobility restrictions associated with Standard Edition Windows Server OS licenses.
"This policy typically requires organizations to upgrade to a higher licensing tier to virtualize workloads. Most enterprises wind up purchasing Datacenter edition licenses as part of a virtualization project, instead of using the licenses that they already own," Wolf said.
Microsoft customers that pay extra for Software Assurance can upgrade to the higher licensing tier by paying an upgrade fee. Microsoft also needs to remove the ties between server OS licenses and physical hardware, Wolf said.
Tying licensing to physical hardware "prevents organizations from bringing their existing server OS licenses to the cloud or to a shared virtual infrastructure," Wolf said. "The result is that cloud providers have to charge more for hosting services in order to absorb the licensing costs."
If the company does not lift mobility restrictions or remove ties to physical hardware when Hyper-V R2 hits next month, customers have some recourse: exerting pressure. Wolf urges IT pros to demand better licensing policies, because vendors have responded with positive changes, albeit slowly.
"The leap to licensing per VM instead of per physical machines is going to take a lot of pressure on the company," Wolf said. "But keep holding them to the fire, because it is working."
Let us know what you think about the story; email Bridget Botelho, News Writer
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