Anyone plz belp me out for creating ...ADS in Fedora/RedHat/CentOS.
Fedora has a project to create AD implementation in Linux. Its called (Fedora Directory Server).
Details : http://directory.fedoraproject.org/
Are you looking at globally replicated servers or all AD servers would be in the same geography. Replication does not work well with FAD / Samba at the moment.
-Shamit http://shamit.in/dpal