Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Possible Duplicate:
Can you help me with my software licensing question?

So simple enough question really, I hope. I'm a little confused by Microsoft's licencing, go figure eh.

I'm maybe looking at providing Hyper-V virtual machines for rental, that is hosting them for rent by customers. Much like you'd get your own VPS from a provider.

Well, I realise with my model I should go with Windows 2008 DataCentre Edition licences, that's the easy bit. My question is do I require External Connector licences (EC), for external users?

If I do, is it per physical machine or per virtual machine/container?

It's very hard to determine this from Microsoft's published documents. They say if the customer/partner is accessing/authenticating to your network then for each server they can access an EC licence is required. Does this though apply to only active directory systems or?

Basically, if I setup all customer's VMs as workgroup servers, just like a VPS I rent, is then a EC licence required. In a nut shell, yes they may be accessing the server/network where the VPS is but they are not specifically autheticating against servers. Essentially this VM is "theirs".

share|improve this question

marked as duplicate by Mark Henderson May 2 '11 at 2:34

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

I don't believe this question should of been closed. I asked a very specific real world scenario ad opposed to the generic dealings of the other question. Yes while Microsoft or resellers may be able to help more direct, more often than not, I find myself talking to a robot on the other end of the phone reading a piece of paper which is far to generic to answer specifics. – Anthony May 2 '11 at 14:09
up vote 1 down vote accepted

This is a licensing model specifically for people who are hosting VMs for customers. Call Microsoft and talk to a Microsoft licensing rep and ask about the hosting provider license. I don't remember what it's called exactly, hopefully someone can comment with the correct name.

share|improve this answer
I think you're thinking of the SPLA (Service Provider License), which is for companies who provide services rooted in MS technologies; perfect example is a web host running Win Server + IIS. I'm not sure if that's what he's doing here. – Chris S May 2 '11 at 0:32
Right so SPLA seems to be the answer. Though I believe when you host websites on iis to anonymous connections, as would be normal web traffic to a server, additional licenses are not required for that server, just the OS license. Or more appropriately, special licensing is not required. – Anthony May 2 '11 at 14:00
Yep, SPLA was what I was thinking of. Through the SPLA program you can get your Windows licenses as well as your external connector licenses (which technically you need, and cost almost nothing). Under the SPLA program you basically rent the licenses from Microsoft and pass that cost along to your customers (at a markup probably). When you don't need the license any more (your customer stops paying you) you can stop paying Microsoft for it. – mrdenny May 3 '11 at 8:37

If you are creating the VMs and selling the services those VMs provide (even if the customer configures custom software, or the base software themselves) you want an SPLA Licecnse. Call MS Licensing and they'd be glad to give you the details.

If you are just hosting images provided by the customer and have nothing to do with configuring, installing, or otherwise provisioning the software or a license to use/run the software then you're getting into a gray area where you likely do not not need your own license to provide this service (the customers would need their own licenses just as if the machine was running on their own premise equipment). You should contact a lawyer to precisely clarify your environment and offerings, if for nothing else to write the TOS for your service.

share|improve this answer
In relation to your separate ideals, it would be the former. There would be management on my part as there is on most hosting companies. – Anthony May 2 '11 at 14:10

tl;dr: You probably do not need an EC for Windows "VPS's", but I think you will need a Windows license and at least one CAL for each one.


I'm going to preface this by saying I've only been involved in setting up Windows licenses, not purchasing them. I don't know the prices well, and can't advise you in any decisions involving costs.

Windows Server 2008 seems to have two different licensing mechanisms to choose from.

  1. Windows "Client Access Licenses" (CALs). These are per-client licenses, in which there must be one license for every client of the server. The "client" can either be a person who may access the server via any device ("per-user" license) or a device which may be used non-simultaneously by multiple people ("per-device" license). I have set up license servers for CALs, typically per-user licenses for Remote Desktop sessions. As I understand it, these are not terribly expensive.

  2. External Connector licenses (ECs). These seem to be an alternative to CALs where you pay for the server rather than the client, to make licensing simpler when you have potentially many infrequent users. (So you don't need hundreds of CALs). Note that AFAICT, the EC applies to a single instance of Windows, so if you have multiple instances of Windows in separate VMs, you would need one for each VM. I think these are more expensive than CALs.

You should also keep in mind that you will need a Windows license, not just a user license, for each of the VMs as it is a separate Windows installation. (Though with Hyper-V I think you get the first one free.)

Windows licensing is complex, so the best thing to do is probably to talk to your Microsoft rep. They may have special licensing for just this situation. But if you're talking about running many instances of Windows in VMs with probably one user each, I think what you need is a Windows license and a CAL for each. Thankfully MS licenses do get cheaper when you buy in bulk, and there are ways to reduce costs. If this is a new business, look into the BizSpark program.

Edit: shortly after writing this, I found a Microsoft Volume Licensing page with basically the same explanation of what I wrote above, and some pretty pictures. The links from there may be useful.

share|improve this answer
Hosting for other businesses = You need SPLA. None of the stuff you mentioned applies, unfortunately. – Chris Thorpe May 2 '11 at 3:30
I also tend to agree that your explained scenario does not apply. Remember, cals are used for direct authenticated access by multiple users above the normal usage of the administrator account. In this and indeed most rented vps, the only access is by the administrator account and as such no cals are required. If the vps was being used as a cloud server for the office then yes possibly cals would be required for the staff and partners that would use service on that vps. An ec license would be more cost effective over individual cals where an unknown amount of users are present. – Anthony May 2 '11 at 14:17

Not the answer you're looking for? Browse other questions tagged or ask your own question.