We have single domain single forest.
Most of our servers are Windows 2008R2 and some Windows2003.
When we install Windows 2008R2, it is asking as to activate the product, which is understandable.
But if we choose not to activate it, and we add machine to domain, then it says the machine validated and activated.
We dont seem to run any licensing servers or anything? Maybe we do somewhere that I dont know.