Looking thru all the documentaiton to create a Windows 2008 R2 Core Domain Controller was a little challenge as there are confusion between the documents. here is an example to create your Domain Controller.
dcpromo /unattend /InstallDns:yes /confirmGC:yes /replicaOrNewDomain:replica /replicaDomainDNSName:domain.com
/databasePath:”e:Windowsntds” /logPath:”e:Windowsntds” /sysvolpath:”e:Windowssysvol”
/safeModeAdminPassword: password /rebootOnCompletion:yes
If you will like more details use this link.
http://technet.microsoft.com/en-us/library/cc772154(WS.10).aspx