Hi Sam,
As Raynald said, you don't need Hyper-V role for VMM 2012 installation, especially if you install VMM 2012 on virtual machine. If you install VMM on physical server and you want to use this server as a host you need to install Hyper-V role
on that physical server.
NOTE: Hyper-V role cannot be installed on the virtual machine!

Romeo Mlinar
MCSA, MCSE, MCTS, MCITP
Blog: Admin troubles
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