Using a Sysprep image gives us the capability to create any number of servers with the base install on a VM done once. You can make a copy of the image to use as the boot drive of a new machine with an expandable or fixed disk.
1) Create the Image, Install the OS on a Hyper-V Guest.
Open Command Prompt and run Sysprep… CD %WINDIR%\system32\sysprep then sysprep.exe /generalize /shutdown
2) Create the Virtual Machine
3) Create the Virtual HD for the machine (using differencing disk. optional) and walk through the "First Run" steps of the OS entering machine name, key etc as you normally would on a fresh install.
For windows server 2008 R2 these are the only Roles that will work after running sysprep
Not all server roles support the System Preparation tool (Sysprep). If you run the sysprep command together with the /generalize option against a Windows Server® 2008 or Windows Server® 2008 R2 installation that has specific server roles configured, those server roles may not continue to function after imaging and deployment.
For the server roles that do not support Sysprep, you must enable the server role and configure the role settings after imaging and deployment.
The following is a list of server roles and whether the roles support Sysprep.
Application Server, DHCP server, File Services, Hyper-V (not V Network) , Print Services, Web Server (Internet Information Services) Remote Desktop Session Host (Terminal Services) but Not supported in scenarios where the master Windows image is joined to a domain.