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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".
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.
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.
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.
Detail:
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.
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.
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.