Microsoft, of all companies, continues to lead the way with free and loose licensing terms around server virtualization software and multi-core processors.
As of Oct 1, Windows Server Datacenter Edition operating system customers will have the right to run "an unlimted number of virtualized Windows Server instances." This policy applies to licenses covering new servers and previous licenses upgraded with new version rights. All told, it means that you pay to run Windows Server Datacenter Edition on a server with a set number of processors and can then divvy that box up with any combination of Windows Server Standard Edition, Enterprise Edition and/or Datacenter Edition without needing to count the number of virtual machines being created or pay for extra Windows Server licenses.
Customers playing with server virtualization software have long complained about the licensing ambiguities that come with running multiple operating systems and applications on a single machine or "pool" of servers.
The one-to-one relationships that once existed between servers and applications has started to erode. In truly virtualized data centers, applications can be moved from server to server depending on demand or failures, and software is spread across all systems in a much more fluid manner.
Some companies such as Cassatt offer tracking services to see how often a customer, for example, uses their Java application server software, what kinds of systems the software runs on and how many users are being served. With such data, customers can then hypothetically go to BEA or IBM and claim they should only pay for X number of application server licenses.
Microsoft's new model could make this simpler on the operating system front by not forcing customers to keep track of any server slicing minutiae.
Redmond has made similar moves on the multi-core processor front, saying customers need only count the number of "chips" they have in a system rather than individual cores for per processor licensing schemes.
These liberal policies have proved shocking to some who associate Microsoft with licensing shenanigans and vice-like software purchasing plans. Microsoft, however, is the underdog in the server virtualization game at the moment. It's far behind leader VMware in terms of market share and behind all major rivals from a pure technology perspective. So it needs to play nice.
In addition, Microsoft's moves could help it gain traction against the IBM/Oracle/Unix (IOU) crowd that have proved more reticent to adjust their software pricing models. Hence the focus on the Datacenter Edition.