Confirm Microsoft Server licensing in clusters

[defrogger]

Hello, just wanted to confirm my understanding of how the Microsoft licensing works.

Just to keep things simple.  Lets say I have a Blade chassis with 8 Blades,so 8 Physical servers with 2 physical processors in each blade. 

One Vcenter server that is virtual

About 50 Vm's

If I had one HA cluster with all 50 Vm's spread out throughout the 8 Blades then I would need 25 (Windows Licenses) * 8 (physical Servers) = 200 Windows Server Licenses or 8 Datacenter server licenses.  This I believe i have right.  You get two VM's per license thats why im cutting in half

But what if I split it it up into 2 HA Clusters?  Spreading out roughly 25 VM's between the two clusters with 4 Blades in each cluster.

Then the math would work out to be

13 (Windows Licenses) * 4 (physical Servers) = 52 Windows Server licenses per cluster, so 104 licenses total.

Big Difference if it works out that i can split the clusters like so. 

Now if there was an actual Microsoft Audit, do they look at it and see 8 Physical servers and require the 200 licenses or do they look at it from a cluster standpoint?

Hopefully that made sense

[prasannag6]

Couple of points to take into account in this scenario:

1. During host failure (i.e. when HA kicks in), VMs get migrated to other hosts. So all the hosts should be licensed with these additional VMs taken into account. The planning part here can be avoided by going for Datacenter edition.

2. Slightly related point - windows licenses cannot be reassigned between hosts within a 90 day period.

[MattiasN81]

It depends what type of licenses you have, if u have SA contract on them you dont suffer from the 90 days "Machine Lock"

if u dont have SA then u have 2 options

* datacenter licenses (1 license per CPU in VMware host, and DC licenses don have any limitations, deploy and VMotion how many VMs u want)

* upgrade licenses with SA contract, otherwise u arent allowed to VMotion back and forth (unless hardware failures)

[vNEX]

Hi,

as others already point out your best option is to buy Microsoft Datacenter license  ... one per hypervisor CPU/Socket allows you to run an unlimited number of instances of Windows Servers simultaneously in virtual OSEs (ESXi servers)

Any additional info about that topic is here:

Microsoft Licensing with VMware | Licensing Articles

Microsoft Volume Licensing Brief - Licensing Microsoft Server Products in Virtual Environments

http://download.microsoft.com/download/3/D/4/3D42BDC2-6725-4B29-B75A-A5B04179958B/WindowsServer2012V...

Once you have all the necessary CPU licenses you have to activate deployed MS servers via MAK key or KMS server with appropriate keys given by MS/DELL.

With MAK you have to manually enter this key on every server separately ... with KMS you will need to install KMS server into your environment and activate him with given key.

Once its done your servers should find KMS server on network and activate automatically...for more details see:

Deploying KMS Activation

Using MAK Activation

[defrogger]

Hello, and thanks for all the replies. 

In this scenario money wise going datacenter licenses would definitively make sense. 

I guess the question is, are you allowed to split things up into HA clusters to save on Microsoft licensing.  Assuming it makes sense for you environment. 

So lets say you only had 10 VM's and 8 Physically servers, yes this does seem unrealistic, but just for the sake of argument, If I had one HA cluster with 8 physical servers then i would have to buy 5 Microsoft licenses for each physical server.  So 40 licenses total.  Or buy 8 Datacenter licenses.  In this case buying individual licenses would probably be cheaper then the datacenter licenses.

But if I split it up into two HA clusters, so 5 VM in each HA cluster, and say 4 physical servers in each Cluster (yes thats allot of physically servers for so little VM's, just an example), so then I would need allot less Microsoft individual licenses as long as the VM's never get moved over to the other physical hosts.

Is that allowed, I just dont want to break any Microsoft Licensing.  Im assuming its just on me to make sure the VM's never get migrated to the other hosts. 

The reason i ask is we have some clients that already have individual licenses and no software assurance, so going up to datacenter licenses could get pricey just to add a handfull of VM's.  

So im trying to figure out if I setup multiple clusters and only allow certain VM's to go onto certain hosts if im still working wtihin Microsoft License agreements. 

In the end it might not make financial sense to go this route or it might not make sense to limit the VM's to only a certain amount of physical hosts, that part ill figure out later, but for now I just need to know if its legal to do that?

Thanks

[vNEX · Accepted solution]

I don't know with which licensing you operate assuming it is Server 2012 licensing model which is completely different from previous on 2008 Servers...

First Datacenter license is only worth if your environment has plenty of VMs and gradually increase in numbers ...

For low density virtual environments for example 50 VMs/on 8+ blades or an absurd scenario of 10VMs per 8 blades your choice is definitely Standard licensing.

One Standard edition license entitles up to two VOSEs on up to two processors (2 socket server) = 8x Standard license enables you to run up to 16 VOSEs on 8 blades...

For detailed and precise licensing info see this document:

http://download.microsoft.com/download/F/3/9/F39124F7-0177-463C-8A08-582463F96C9D/Windows_Server_201...

So lets say you only had 10 VM's and 8 Physically servers, yes this does seem unrealistic, but just for the sake of argument, If I had one HA cluster with 8 physical servers

then i would have to buy 5 Microsoft licenses for each physical server.  So 40 licenses total.  Or buy 8 Datacenter licenses.  In this case buying individual licenses would probably be cheaper then the datacenter licenses.

Why 5 MS licenses for 1 physical server ??? With Server 2012 licensing model you only need 1MS Standard license per Blade for example above.

But if I split it up into two HA clusters, so 5 VM in each HA cluster, and say 4 physical servers in each Cluster (yes that's allot of physically servers for so little VM's, just an example),

so then I would need allot less Microsoft individual licenses as long as the VM's never get moved over to the other physical hosts.

Is that allowed, I just don't want to break any Microsoft Licensing.  Im assuming its just on me to make sure the VM's never get migrated to the other hosts.

Yes you can use DRS affinity rules to restrain VMs only to licensed hosts but regarding this I would ask some MS licensing specialist or license supplier.

For more on that read "Q: What are my licensing options for the recovery server as part of disaster recovery planning?" section of document above.

[prasannag6]

In this scenario: 8 Physical Servers running 10 VMs. I am confused as to why we need 5 licenses/hosts? First step is calculate planned number of maximum VMs running on single host at any point of time. If only 2 VMs will run, we just need 1 standard Windows server license. In total we need only 8 licenses. So it doesn't matter whether we split into two clusters are not, we always license based on number of VMs running on single host. The other advantage I can see in single cluster is, we will have lesser number of VMs running in single host during host failures.

(1 standard Windows server 2008 license covers 2 physical processors, and 2 VMs are allowed. Enterprise covers 4 VMs).

[MattiasN81]

Ms licenses works this way.

1 license per server, it dosent matter if its a virtual or physical servers, however some limitations apply on virtual servers

Limitations.

* Without SA contract on each server license you arent allowed to move around the VM between hosts, if u move the VM to another host  then that host need to run that VM for 90 days until u can move it back, there are no technical limitations to move the VM anyway, just you arent allowed to.

* Any "per server" license is bound to that server by license agreement, so u cant just turn one server down and power up another and think thats enough.The same rule also apply to datacenter licenses, for example, if u have 2 vmware-hosts with 2 CPU each, then u have 2 DC licenses, those licenses are bound to those hosts, so if your DC burns down u arent allowed to "move" those DC licenses to a secondary site.

[defrogger]

Thanks for all the replies.  So it looks like i can split things into Clusters to save on licensing, now i just have to see if it makes sense to do so.  I will take your suggestion and talk to Microsoft Licensing to confirm things though if I ever decide to go down this route

[danielczh]

I am pretty sure that Windows Server is not eligible for License Mobility whether within Server Farms or through Software Assurance.

Easiest way to picture Windows Server licenses is that it is a piece of paper license that you physically stick/glue on to a physical box. That paper license represents how many servers (physical + virtuals) that can be licensed at any one time on that physical box. You can only move that paper license once every 90 days or upon hardware failure.