I'm testing this out and so far have installed using the Debian/3CX iso on a Hyper-V VM inside Windows Server 2012r2. I haven't yet tried to install it directly on the server core or on the VM for the domain controller. My first VM was set running two processors and 2048mb of RAM. I only had four users for testing but did encounter a kernel panic this morning and it noted it ran out of memory. I upped the RAM for 4096 to see how it changed things. For others out there that have tried more than one variation, which one seemed to work the best for you? Dedicated box with Debian/3CX, dedicated Windows box, Debain VM or Windows VM? Thanks for your input.