at least 1 Win2k8 DC, forest functional level min. 2003
win2k8 has to have the PDC emulator role ( FSMO )
prepare the forest, adprep /forestprep ( must be run on schema master )
prepare the domain, adprep /domainprep ( must be run on infrastructure master )
prepare the domain, adprep /rodcprep
adprep is found on the windows 2008 DVD, and off course run it from a elevated command prompt
note : adprep is only necessary if we are introducing a win2k8 server in a win2k3 domain
RODC’s can be ether a core or full installation.