Mordtech's Blog

General Technology Blog

Microsoft licensing

We are beginning to go a usage audit to true-up our Microsoft licensing. For the most part, the licensing is straight forward. Use a product, get a license. Don’t use the product, don’t get a license. But where confusion creeps in is around items such as virtualization, Public web access, Clustering. In this blog I’ll discuss Microsoft licensing in the virtualization arena. I’ll write another entry on public web access and clustering within the next day.

Licensing in the virtualization arena:

You have three options for licensing the Windows Server operating system. The first is that you buy a license for each virtual machine based on whether it is running Windows 2003 Standard or Enterprise: Easy enough. Option two is a bit more tricky, according to the Microsoft licensing for Virtualization web page, you can run “…you to run up to four software instances at a time in virtual operating system environments (OSEs) on a server under a single server license.” The third option is to purchase a license of Windows 2003 Datacenter, which is licensed per socket, for each of your Physical Hypervisor Hosts. This allows you to run an unlimited number of Windows Server based guest VMs on that particular host.

Lets look at a quick cost benefit analysis of each licensing type. We will use a two node cluster of dual processor Quad core servers. We will exclude networking, storage, electrical and cooling consumption. Those would be similar under any of the three licensing options. I also won’t even begin to do a hardware cost comparison between physical and virtual as there is enough information on the web to make an accountant cry about how much you will save virtualizing your environment. We will use a Server vCPU to pCPU ratio of 5:1, which should give us roughly 40 vCPUs. Given that we need the overhead to allow a hardware failure, we will not account for the second Host node. We’ll break down the license usage as 34 Windows 2003 Standard and 6 Windows 2003 Enterprise Guests.

License option 1: (one license for each Guest VM)

   MSRP Amount Option 1 Cost










As you can see in the graphic above, the MSRP of those 40 servers would be approximately $58,000.

License option 2: (Windows Server Enterprise – 4 free on the same server)

   MSRP Amount Option 2 Cost





Here is where it can a little dicey, the license states that you can run 4 instances of the OS on one server. When you license in the two node environment, especially when using a product such as VMware Infrastructure DRS; you can not be sure how many VMs will reside on one physical host at any one time. It might be 20-20 or it might be 22-18, etc.. While it would look like you only need 10 Enterprise licenses to cover those 40 servers, you would probably need at least 1 extra for each node to ensure that you never have more guest VMs running on one node. Even with purchasing two extra licenses of Windows Enterprise, you still save $6,000 over the one-license per guest option. Another benefit is that you can run either Standard or Enterprise and still be in the good graces of Microsoft.

License option 3: (Windows Server Datacenter – run what you brung!)


   MSRP Amount Option 3 Cost





Here is where Microsoft licensing in the virtualized arena begins to shine. Microsoft DataCenter licensing has an MSRP of $2,999 per physical processor. Not per core, per physical socket. That means that for each node in the cluster, we need $6,000 worth of Microsoft OS, to cover everything. This licensing option also allows us the opportunity to load whatever OS, the business unit needs. Or, we just standardize on Windows Enterprise for the Virtualized servers and not worry about any features that are disabled on the standard version.



Microsoft Licensing for Virtualization:

Microsoft Windows Server 2008 Pricing:

1 Comment

Comments are closed.

Mordtech's Blog © 2015
%d bloggers like this: