Just a couple of weeks ago, we provided a quick take on licensing options for Windows Server 2012 that enterprise IT leaders will need to consider as they plan their OS migration strategies. (See Windows Server 2003 Isn\u2019t Broke: So Why Fix It?). Up next, we\u2019ll dive deeper into Windows 2012 licensing.\nWe\u2019ll start with considerations for any impacts to legacy versions, at least regarding the Software Assurance program and its benefits. Are there any systems in your data center currently covered by Software Assurance? If so, those covered by Software Assurance today already operate under the use rights of Windows Server 2012.\nIt can be cloudy to properly calculate your grants for the newer products. The first thing you will notice when looking at the product list, is that there is no longer a Windows Server Enterprise version. So how are you supposed to calculate the number of licenses you are granted here? Well, IT focus has been shifting to virtualizing in a private cloud, so Microsoft graphed their grants with this in mind. Each Windows Server Enterprise 2008 R2 license covered by Software Assurance at the release of 2012 can be renewed with two Windows Server Standard (a ratio of 1:2). This carries over the customer\u2019s entitlement to four VMs (something they had from Windows Server Enterprise).\nHow about Windows Server Datacenter? They were originally sold as single-processor licenses. Now, they are sold as two processor licenses. So that any two previous Datacenter licenses can be renewed with one 2012 Datacenter license. A four-processor server, for example, now needs just two licenses to cover all those processors.\nAny licenses not covered under Software Assurance will need to be upgraded by purchasing a full license. Keep in mind, however, that the calculation for the number of licenses needed changed with the 2012 version. With 2012 (and subsequently 2012 R2) there are only two main editions: Standard and Datacenter. Both allow for the same hardware utilization and cloud ready feature set. The only difference between them is their virtualization rights. Both editions cover physical machines with two processors\u2014they just do it a little differently.\nWindows Server Standard will cover either a physical OSE (operating system environment) that exists on a machine with two processors or two virtual OSEs that are stackable on a given virtual host. These two virtual OSEs cannot be split across two physical hosts. Two physical servers with three virtual OSEs each would require four licenses, not three.\nWindows Server Datacenter, however, covers a host machine for unlimited virtualization, given that the proper number of physical processors are licensed. Seeing as the license is a two-processor license, a machine with three or four processors would require two Datacenter licenses. Like the virtualization benefit for the standard edition, this entitlement cannot be split over two hosts. Two physical servers with three processors would require four licenses, not three.\nWhat do you do, though, if your Software Assurance license grant does not cover all the processors on some physical servers as you transition to the Windows Server 2012 licensing model? That\u2019s going to be a concern particularly for IT environments characterized by higher processor-dense servers, and there are many of them out there. The good news is that it is possible to qualify for a one-time grant to receive the number of additional licenses needed to cover those servers for free. It will take some work, though, in terms of documenting inventory, so start that process sooner rather than later.\nWindows Server 2012 represents a sea change, and the conversion to it provides IT with an opportunity to reset the data center stage for a more cloud-conscious world. That\u2019s an opportunity not to be missed.\nWith the end of support date for Windows Server 2003 fast approaching, there's never been a better time to plan your data center transformation. Our experts have designed this helpful tool to get you started on the right upgrade path for your unique environment, applications, and workloads.