Microsoft Moves to “Per Core” Licensing for Windows Server

Microsoft has (pretty predictably) moved to “Per Core” licensing for Windows Server, just like SQL Server before it. This is more to the trend of denser servers – that is, with more and more cores per server – and, possibly, in a nod to Azure.

It’s been pretty well documented, but there are minimums:

  • A minimum of 16 core licenses is required for each server.
  • A minimum of 8 core licenses is required for each physical processor.

And, like for SQL Server, there is a “trade in” program, more officially referred to as a “grant” program, that will follow along the same lines as the SQL Server program. Specifically, for every license of Windows Server 2012 R2 that is covered by Software Assurance, the customer will receive an equivalent number of “Per Core” licenses for no additional license charge. Yes, I stressed the word “license” and we’ll get back to that in a minute.

If these large beefy machines are already in place – those with more than 8 cores per processor – then you can get these licenses free of charge as well. You have to make your case, of course, by sending Microsoft information via the Microsoft Assessment & Planning or “MAP” Toolkit. This will validate the servers’ configurations.
Now, I mentioned that there will be no license charge. And that’s true. However, since you must continue to pay for Software Assurance, those fees will be based on the new number of licenses. So if you received an additional 20 licenses, for example, you will be paying an additional 20 licenses’ worth of Software Assurance.
(This will also foul up your Microsoft License Statement or “MLS”, but that’s a different story.)

But there are two somewhat major “gotchas”:

  1. Since forever, the different editions of Windows Server were technologically different. That ended for Windows Server 2012 when the two primary editions, Datacenter and Standard, had the same feature and functionality set. The only difference was in their virtualization rules. Now that has ended. Once again, there are technological differences, including:
    • Storage Spaces Direct
    • Storage Replica
    • Shielded Virtual Machines
    • Networking stack
    • But not Nano Server… that’s part of Standard Edition as well, BUT… Software Assurance coverage is required to deploy Nano Server.
  2. The virtualization practice of “stacking” licenses doesn’t work so well any more for Version 2016. Under the 2012 and 2012 R2 rules, licenses of Standard Edition could be “stacked” to allow more virtual instances to be supported. For example, if Windows Server Standard was deployed on a server with 4 processors, two (2) licenses would be necessary (as each license covers up to 2 processors). This allowed up to 4 VMs on that server because each license permitted up to 2 VMs. If you needed another VM or another 2 VMs, just allocate another license to that same server.

    That doesn’t work with Version 2016. First, all physical cores have to be licensed, so for this server, at least 32 cores – or 16 licenses – are needed. That allows for up to 2 VMs. If another VM or another 2 VMs are needed, then the entire server must be licensed again! That is, another 16 licenses. Maybe that’s not so earth-shaking for our example, but in an environment where many VMs are needed, then it’s logical to assume that it’s a larger server, with more cores. So those 16 licenses could very well turn into 20 licenses, or 24 licenses, or more!

So, clearly, Microsoft has made Datacenter Edition the only practical choice for heavily virtualized environments.

And don’t forget System Center follows suit… as far as “Per Core” licensing and minimums and virtualization rules go…

And, yesterday, general availability for Windows Server 2016 and System Center 2016 was announced for the October timeframe.