Blog Archive

Per-Core Licensing FAQ

Windows ServerWindows Server 2016 (Standard and Datacenter Editions) and System Center 2016 will be changing to per-core + client access licence (CAL) when they are released towards the latter part of 2016.  We briefly blogged about the change earlier and we’re seeing a lot of the same questions so why not use that as an excuse for another post?

Why change?

The world is becoming cloudier and these licensing changes enable customers to operate more easily across on-premises servers and private and public clouds because we can just use a consistent currency of cores that simplifies licensing of hybrid use cases.  For example, a two-processor licence of Windows Server 2012 R2 on-premises today is translated into 16 cores of Microsoft Azure use right benefit.  If both of these environments are core-based it’s a nice easy transition.

Will I Still be Able to Virtualise with Standard Edition?

The case for licensing Datacenter Edition is for high-density virtualization, private clouds and hybrid cloud use.  The keys to making that successful are automation and being able to define networking, storage and the like with software rather than physically connecting network cables.  So Datacenter Edition will provide advanced software defined datacenter capabilities to make it the ideal for highly virtualized or private cloud environments.

Standard edition will not these features or will have them in more limited form.  Hyper-V is still included in both editions however and you can still virtualise in Standard Edition.  It will continue to be ideal for low density virtualized scenarios, including the use of containers and in some instances it makes financial sense over Datacenter Edition.

If you’re concerned that your solutions running on Windows Server 2012 Standard edition may not work after an upgrade, fear not; no pre-existing features are being moved from Standard to Datacenter.  Datacenter will be a superset and contain all the features of Standard edition.

Even though we’re writing about licensing in this post, we should cover a couple of Windows Server features just because they might affect how you licence.  Namely, Hyper-V containers, Windows Server containers and Nano Server.

Hyper-V Containers and Windows Server Containers

Historically, each server application would run on its own physical server; a 1:1 application to server ratio to ensure no conflicts with existing applications and workloads.  This resulted in a large number of physical servers, all typically with low utilisation.

Virtualisation of multiple applications onto a single physical server is now prevalent and we enjoy significantly higher consolidation ratios, greater utilisation and faster application deployment times measured in minutes rather than hours or days in a purely physical datacenter.  Plus all the benefits of virtualisation such as higher levels of redundancy and mobility.

There is however, a new and increasingly popular way to build, ship, deploy and instantiate applications: containers.

Whereas virtualisation is still 1:1 application to OS, albeit a virtual OS, containers can run multiple isolated applications on a single OS known as the control host.  And containers can run on a host OS which itself could be physical or virtual, so that’s fantastic flexibility.

That’s the difference between a Windows container and a Hyper-V container.  A Hyper-V container has a virtual host OS.   A Windows container uses the physical OS as the host.

With Windows Server 2016 Datacenter, you can run unlimited containers just as you can perform unlimited virtualisation.  With Standard Edition you are entitled to have unlimited Windows Containers, because they run with the physical OS as the control host.  Hyper-V containers follow the same rules as virtual operating system environments (VOSE) in that you are allowed two virtual control hosts every time you completely licence all physical cores on the server.

 

Virtualisation Licensing for Windows Server 2016

 

But why do we need containers?  What do containers provide that virtual machines can’t?

For the developers, containers unlock the ability to build an application, package within a container, and deploy, knowing that wherever you deploy that container, it will run without modification, whether that is on-premises, in a service provider’s datacenter or in the public cloud such as Azure.  You can also have complex multi-tier applications, with each tier packaged in a container.

Nano Server

So that’s containers in a nutshell.  What about Nano Server?  Is that a special edition for my granny?

If you are hosting lots of VOSEs, the last thing you want is for the host OS to reboot because that means everything I’m running on that host either needs to migrate to another server or also reboot.  You want to minimise what’s running to reduce the resources used and the surface area open to bugs and attacks. Yes, I used the B word.

Windows Server 2008 came up with Server Core which was a hugely reduced installation intended to just support specific workloads such as hosting VOSEs.  Windows server 2012 improved Server Core so it was more modular and you could install and configure the server and then switch into Server Core whereas in 2008 it was an either-or choice at installation.

 

Windows Server Core between 2003 and 2012

 

Windows Server 2016 goes further with Nano Server.  Just to give you an idea of the scale here, the charts below compare setup time, disk footprint and VHD size between the already trimmed Server Core installation and the new Nano Server.

 

Windows Server 2016 Nano Server

 

Now the big question here is how do you licence Nano Server?

Well, Nano Server is a deployment option within Windows Server 2016.  It’s included as part of the licensing of both Standard and Datacenter editions so there is no unique or separate licensing for Nano Server.  Good news.

Look Like an Expert with these Extra Facts

Q – Will the Core Infrastructure Suite SKU also be core based licensing?

A – Yes, Core Infrastructure Suite is a single SKU incorporating both Windows Server and System Center at a discount.  This will also be core based when Windows Server and System Center are released.

Q – Is the Windows Server External Connector available at the release of Windows Server 2016?

A – Yes, the Windows Server External Connector license will still be available for external users’ access to Windows Server.   Just like it is today, an external connector is required for each Windows Server the external user is accessing.

Q – How should I think about hyper-threading in the core based licensing?

A – Just count the physical cores.  Windows Server and System Center 2016 are licensed by physical cores, not virtual cores.  So you only need to inventory and license the physical cores on the processors.

Q – If processors (and therefore cores) are disabled from Windows use, do I still need to license the cores?

A – No, if the processor is disabled for use by Windows, the cores on that processor don’t need to be licensed.  For example, if 2 processors in a 4 processor server (with 8 cores per processor) were disabled and not available for Windows Server use, only 16 cores would need to be licensed.  However, disabling hyper threading or disabling cores for specific programs does not relieve the need for a Windows Server license on the physical cores.

 

Don’t Forget CALs

Windows Server Standard and Datacenter editions will continue to require Windows Server CALs for every user or device accessing a server (See the Product Use Rights for exceptions).

Some additional or advanced functionality will continue to require the purchase of an additive CAL.  These are CALs that you need in addition to the Windows Server CAL to access functionality, such as Remote Desktop Services or Active Directory Rights Management Services.

Feel free to contact us if you have any questions – we love to hear from you!