Moving RHEL6.2 HDD from one machine to another.

Hi All.

I am in an environment where I need to set up one master RHEL hdd on a workstation, and clone the hdd to use on multiple other workstations. (we are arranging the licenses to cover all active workstations).  There appears to be an issue that the hdd will only work in the workstation that it was built in.  If I attempt to plug it into another machine, it is not recognised as a valid boot device.  We have verified that BIOS settings are exactly the same.  The difference is that the original workstation recognises the drive as "Redhat Enterprise Linux", and the other workstations don't (however if I boot up Clonezilla I can verifiy that the HDD is physically there).

Can anyone advise one way or another?

Thanks in advance.
Owen.