Microsoft Licensing for multiple ESX servers

[TheNuts]

I am trying to get a little less confused on the subject of licensing and ESX.

We are just starting to get into virtualization and have purchased 2 ESX servers Enterprise edition with vCenter. We run mostly Windows 2003 Standard Edition servers. Our plans are to P2V a subset of our Windows servers and use vmotion for HA. We will be also adding some future non P2Ved VMs.

From my reading, if I were to P2V let's say 10 of our W2k3 servers I would need 10 additional W2k3 licenses in order to migrate them via vmotion to another ESX server in a cluster. Is that correct?

Datacenter license...it is my understanding if we purchase a Datacenter license, we don;t have to worry about adding any additional licenses to any ESX servers. Correct?

If we have 2 physical ESX hosts, each with 2 procs, and wanted to purchase Datacenter, we would have to purchase Datacenter 4 processor license? If we added another 2 proc ESX server, we would have to purcahase another Datacenter 2 processor license?

[VladN]

if I were to P2V let's say 10 of our W2k3 servers I would need 10 additional W2k3 licenses in order to migrate them via vmotion to another ESX server in a cluster. Is that correct?

If you power off and recycle source servers then no. To use vMotion you don't need two licenses for one VM.

Datacenter license...it is my understanding if we purchase a Datacenter license, we don;t have to worry about adding any additional licenses to any ESX servers. Correct?

Do you mean Enterprise/Enterprise Plus license ? vSphere doesn't have Datacenter license? Or you mean MS license?

If we have 2 physical ESX hosts, each with 2 procs, and wanted to purchase Datacenter, we would have to purchase Datacenter 4 processor license? If we added another 2 proc ESX server, we would have to purcahase another Datacenter 2 processor license?

Yes, if by Datacenter you mean Enterprise...

[TheNuts]

About licensing a 2nd ESX server with Microsoft licenses, I came across this...

In contrast, Microsoft's licensing policy has some restrictions on transferring licenses from one server to another. Under Microsoft licensing, Windows Server licenses are tied to physical hosts and do not move with virtual machine environments. Reassignment of a license to another server is only allowed once per 90 days except in case of hardware failure, and for more frequent license reassignments, customers are required to separately license each machine to run the server software. This means that the customer will have to either purchase additional Windows Server Standard or Enterprise Edition licenses to cover the potential number of virtual machines that may run on each host machine, or upgrade their Windows Server licenses to Datacenter Edition.

Does this not apply to a 2nd ESX server using vmotion? Or maybe I am not understanding it...

I was referring to Windows Datacenter in my above questions

[VladN]

Here is a discussion regarding MS licensing and Vmotion...

[TheNuts]

OK, if I do not need to purchase additional MS licenses for a 2nd physical ESX host that I am using to vmotion my VMs over to, why would I need to purchase a 4 processor MS Datacenter license for 2, 2 processor physical ESX hosts? Could not I purchase 1 MS 2 processor license for 1 ESX host, install 100 VMs on that host and just vmotion them over to the other ESX host anytime I wanted without worrying about MS licenses?

[VladN]

If you power off and recycle source servers then no. To use vMotion you don't need two licenses for one VM.

Here is what I should have written: To use vMotion once every 90 days for each particular VM you don't need two licenses for one VM. This could work out if you don't use any of the good VMware stuff like DRS.

You need DC license for 4 sockets if you have more than 8 Windows servers running on 2 2-socket ESX Servers even if you cold migrate them between ESX servers more often then every 90 days.

[weinstein5]

The 90 day rule no longer applies now that Microsoft has live migration - they have removed the limitation of only being able to migrate once every 90 days - check out the application server mobility document on .

So you no longer need DC licenses for each host - you only need to license to the number of virtual CPUs in the VM -

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[VladN]

This change does not apply to software licenses for the Windows Server® operating system, etc... (from page 1)

I think licensing of server OS on ESX vs Hyper-V is the only way MS can make people get to use Hyper-V in production right now. If you need to run 100 VMs on 2x 2socket servers you have to buy just 4 socket DC license if you want to use Hyper-V, but if your choice is vSphere, you still have to buy the same license for guest OSes plus vSphere license.

[AsherN]

OK, if I do not need to purchase additional MS licenses for a 2nd physical ESX host that I am using to vmotion my VMs over to, why would I need to purchase a 4 processor MS Datacenter license for 2, 2 processor physical ESX hosts? Could not I purchase 1 MS 2 processor license for 1 ESX host, install 100 VMs on that host and just vmotion them over to the other ESX host anytime I wanted without worrying about MS licenses?

Could you? possibly. You may be able to get a single proc lic of DC and use that. Or a 5-pack of Standard to get a VLK. But it would all break MS licensing.

You can only vMotion DC licenses to another host with a valid DC license.

[TomHowarth]

to fully license your 2 node ESX environment for Unlimited Windows Guests you need to purchase DataCenter editions ot the CPU count of your total ESX estate.

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Tom Howarth VCP / vExpert

VMware Communities User Moderator

Blog: www.planetvm.net

Contributing author for the upcoming book "[VMware vSphere and Virtual Infrastructure Security: Securing ESX and the Virtual Environment|http://my.safaribooksonline.com/9780136083214]”. Currently available on roughcuts

[matuscak]

A couple of comments... Unless something has changed in the last few weeks (always possible in MS License Land)...

The other part of the game is the relative cost of Windows Standard, Enterprise and Datacenter licenses. The Windows Enterprise Licence allows for four virtualized Windows instances and looks to be priced at something like 3.5 of a Standard license. So for a small ESX host (like a branch office), a Windows Enterprise license can be cheaper than a flock of Standards. It also happens that Datacenter is not a whole lot more than Enterprise, so if you have more than four or five Windows servers, a Datacenter license makes a bunch of sense to me.

You can also upgrade Standard or Enterprise licenses to Datacenter (at least if you have an agreement with SA). So you could potentially license your ESX hosts with Datacenter by upgrading four of your existing Standard licenses.

BTW, at least the way we've done it, we bought two two socket licenses of Datacenter rather than one four. We were told it needed to be licensed to a specific box, rather than a pool of licenses.

YMMV.

[TheNuts]

If I P2V a physical Server 2003 Enterprise box to run on an ESX host, does that give me the licenses to run 3 additional instances of Server 2003 on the ESX host without having to purchase more licenses?

[JoJoGabor]

All the information in this post is correct, WIndows Enterprise License will cover you for 4VMs on a host. Datacenter is licensed per host socket which allows unlimited VMs on that host. If you run more than 15 VMs on a host its usually cheaper to purchase Datacenter edition

BUT there is one thing we are missing:

As long as your current physical servers are licensed for Windows and you are decommissioning the physical servers, converting them to Virtual does not require any additional licenses. This only comes inot play if you are upgrading tio the next version of Windows (2008?)

[matuscak]

"If I P2V a physical Server 2003 Enterprise box to run on an ESX host, does that give me the

licenses to run 3 additional instances of Server 2003 on the ESX host

without having to purchase more licenses?"

My understanding is yes. You would be able to use that license to run up to four VMs. The VMs can be running either Standard or Enterprise versions of 2003 or earlier releases.You would need to kill the physical machine after doing the P2V of course.

[JoJoGabor]

I cant think of any reason why not

[TomHowarth]

Your statement is not fully correct, your P2V's will only be valid if they are not OEM.licenses as these are tied to the hardware that they are installed on.

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Tom Howarth VCP / vExpert

VMware Communities User Moderator

Blog: www.planetvm.net

Contributing author for the upcoming book "[VMware vSphere and Virtual Infrastructure Security: Securing ESX and the Virtual Environment|http://my.safaribooksonline.com/9780136083214]”. Currently available on roughcuts

[AsherN]

All the information in this post is correct, WIndows Enterprise License will cover you for 4VMs on a host. Datacenter is licensed per host socket which allows unlimited VMs on that host. If you run more than 15 VMs on a host its usually cheaper to purchase Datacenter edition

BUT there is one thing we are missing:

As long as your current physical servers are licensed for Windows and you are decommissioning the physical servers, converting them to Virtual does not require any additional licenses. This only comes inot play if you are upgrading tio the next version of Windows (2008?)

The break even is a lot less than 15. From MS website, Standard is $1K, Enterprise is $4K, so they are essentialy the same. Datacentre is $3K per socket. So if youplan to run more than 3 VMs per socket, Datacentre is cheaper.

[TheNuts]

I just got off the phone with an MS licensing rep. He was staing that each physical ESX host needs to be licensed for the number of MS VMs running on it regardless if the VMs are vmotioned to another ESX host. If I have 5 VMs running MS Server Standard on ESX1 and vmotion them over to ESX2 that is just sitting there not hosting anything, I must purchase 5 additional MS Server Standard licenses to be able to run on ESX2. He was saying the same applies for a DR scenerio where VMs would need to be transferred to another ESX host at a secondary datacenter

Is this correct?

Reading the latest (Jan 2009) MS article, I cam across this... In general, as a Microsoft Volume Licensing customer, you may reassign software licenses for products in the Microsoft Servers licensing models, but not on a short-term basis. "Short-term basis" means more frequently than within 90 days of the last assignment (or reassignment). You may, however, reassign software licenses sooner if you retire the server sooner due to permanent hardware failure.

So, I guess you cannot technically vmotion an instance of Server 2003 to another ESX host unless that ESX host has a license for that VM....unless it resides on the other ESX host more than 90 days or the original ESX host bites the dust?

[matuscak]

"I just got off the phone with an MS licensing rep. He was staing that..."

Heh. One of my "favorite" parts of dealing with Microsoft licensing is that if you ask the same question to two different MS reps, you'll get four different answers. I've found the best thing to do get the documentation from the MS site and have it handy to quote back to them. It's pretty funny how frequently you can get them to admit they really don't understand the convoluted mess MS has made of licensing. A good one to have handy is titled "MicrosoftProductUseRights(Worldwide)...".

As it sits today, (prior to MS having a VMotion equivalent), the rep is right about the first case. Assuming that you're talking about recurring VMotions (like with DRS), you need to have Windows licenses on both ESX hosts. The section in the MS document says:

"You may reassign a software license, but not on ashort-term basis (i.e., not within 90 days of the last assignment). You mayreassign a software license sooner if you retire the licensed server due topermanent hardware failure. If you reassign a license, the server to which youreassign the license becomes the new licensed server for that license."

So, if that second server only gets stuff moved on to it less frequently than every 90 days, you're convered with a single set of Windows licenses. In our main site, we ended up just doing Windows Datacenter licensenses on each ESX host since it was cheaper and it completely sidestepped the MS silliness. In a remote plant we have two ESXi hosts, where one is running, and the other one is normally shut down (no VMotion). If the primary host croaks, we can start the backup host and move the VMs to it. In this case, we have a single set of Windows licenses, and our interpertation is that we're legit. That being said, I'll bet a beer that as soon as MS has their live migration on the street they will change the license to allow a single Windows server license to migrate at will.

On the DR front, i'd say if your DR is a hot site setup from the Windows perspective (Windows running), then the rep is right. If, on the other hand, you only plan to move the VMs when you have a disaster, I'd say the basic rights cover that for a single set of licenses.

YMMV, etc.

[TheNuts]

Hopefully with the RTM release of Server 2008 R2 where MS gets live migtation, they will address the issue. I know that have addressed the issue of Application mobility in stating that it is OK to move an app like SQL to another VM without any issues...but the OS license (which of course the app runs in) still runs into the 90 day thing unless of course you decomission the original server.

So, if I need to do maintenance on ESX1 and want to vmotion 5 VMs to ESX2, I technically need to purchase 5 additional MS Server licenses for ESX2, unless I decomission ESX1 or keep the VMs running on ESX2 for at least 90 days?