If you are using Windows 2012 R2 hypervisor and you want to create a VM using one of the following OS:
- Windows 2003
- Windows 2008
- Windows 2008 R2
- Windows 2012
- Windows XP
- Windows 7
- Windows 8
You will notice that in the device manager two devices are in an unknown state.
This is expected because the two missing devices are related to two Hyper-V 2012 R2 features supported only by Windows 2012 R2 Virtual Machines.
The two new features are:
This is a new feature in Windows Server 2012 R2 that makes it easier to use the licensing advantages accorded by Windows Server Datacenter. Windows Server Datacenter provides unlimited virtual machine instances of Windows Server for a licensed system. With automatic activation, Windows Server 2012 R2 guests will automatically activate themselves when running on a Windows Server 2012 R2 Datacenter.
Enhanced Session Mode
In previous versions of Hyper-V, Virtual Machine Connection provided redirection of only the virtual machine screen, keyboard, and mouse with limited copy functionality. To get additional redirection abilities, a remote desktop connection to the virtual machine could be initiated, but this required a network path to the virtual machine.
Starting with Hyper-V in Windows Server 2012 R2, Hyper-V can now redirect local resources to a virtual machine session through Virtual Machine Connection tool. The enhanced session mode connection uses a Remote Desktop Connection session via the virtual machine bus (VMBus), so no network connection to the virtual machine is required.
I will write an in-depth article about these interesting features ASAP.