Hyper-V Server is a free operating system specifically designed to just run Hyper-V so basically a cut down core installation of a paid for edition of Windows Server. The cut down bit refers to the fact that only the roles and features needed to run Hyper-V are there. However Hyper-V itself is in no way cut down; for example you can create clusters for running HA virtual machines (up to 64 nodes hosting 8,000 VMs) and each VM can still have up to 64 logical processes as per the DataCenter edition of Windows Server.
So what’s the catch?
If there is one then it’s that if you want to run Windows Server in a VM it needs to be licensed and the most efficient way to do that once you get to 6-7 VMs per host is to use Windows Server DataCenter edition as this allows any number of guest VMs’ to be licensed for Windows Server as well as the hosts. However if you were going to use Hyper-V to host VDI then your guests need to be licensed for Windows 7/8 and so Hyper-V Server is a good candidate. Another example is if you want to just host Linux VMs which will run really well and are supported (depending on the flavour you are using).
I have made my usual short screencast to show you what it looks like..
Also, you might want to look at the other posts in my Evaluate This series as Hyper-V Server is best managed remotely, and my other screencasts will show you how to do such things as live migrations, VDI, replicate VM’s etc. all of which are possible with Hyper-V Server.
To configure Hyper-V Server for remotes access all I did was use the built in SConfig utility to join it to my domain as remote management is turned on by default in Windows Server 2012, and I have group policy setup to allow remote desktop on all of my servers.
NIC teaming is now viable in server core and Hyper-V server because it’s built into the OS where in earlier versions of server you might not have been able to install the hardware vendors NIC teaming software without a user interface.
Hyper-V Server like the server core installation option of Windows Server only needs half the patching of a full installation of Windows Server.
Hyper-V Server 2012 now includes Powershell out of the box.
Finally you can get Hyper-V Server 2012 here and try it yourself and put it into production if needed.
So if I wanted to clone some of my existing physical servers into my evaluation Hyper-V environment to do some testing how would I go about doing that?
You would convert the hard disks of your physical machines to Virtual Hard Disks for example using Disk to VHD (gallery.technet.microsoft.com/Convert-Disk-to-VHD-in-ff4900f7) then you would note the specs of your server (number of cores ram etc. and create a new VM based on those and then mount your VHD and you are all set. However in Hyper-V Server so you'll either do all of that from the management tools installed on another server or get up to speed on the necessary PowerShell commands.