So you want to virtualize Hyper-V on Hyper-V.....it is possible, well up to a point. Attempting to enable the Hyper-V role on a Full install of Windows Server 2008 or Windows Server 2008 R2 will fail with an error that says that the required virtualization features are not required. This is because Hyper-V needs the virtualization extensions that Intel and AMD have added to their processors. These features are no fully available in a Hyper-V child partition. Hyper-V installation routines has added logic that looks at the processor in the machine you are installing to determine if those features are there. If the features are not found the GUI installation wizard will popup a dialog that prevents the installation of the Hyper-V role.
Server Core does not have the block and you can actually enable Hyper-V role on a server core virtual machine. You can even create a cluster using the virtual machines. You are still blocked to actually starting a virtual machine becuase the hypervisor cannot start due to the lack of the virtualization extensions in the child partition.
Note that this is not supported by Microsoft
