Hello, Can anyone suggest Me a link or provide me appropriate documentaion for using OpenLdap as a Windows Client Authentication in RHEL-4. Basically I want all my window client which are running windowXP to authenticate using openldap instead of using Active directory for Centralized Authentication . In short I want to replace Active directory by openldap.

I'm not sure about any links, but I can provide some basic information that you can use as a starting point:

One approach is to use Samba (http://www.samba.org) and OpenLDAP together, having configured Samba to use OpenLDAP. Samba provides the Windows Domain infrastructure, as well as file and print services. On the pro side, this solution is a server-side only solution and works with unmodified Windows workstations. On the con side, configuring Samba to work with OpenLDAP can be a daunting task.

A second approach involves using pGina (http://www.pgina.org) with its LDAP authentication module. This is a more stripped-down approach that won't provide Domain, file, or print services. On the pro side, it's a simpler implementation and easier to understand. On the con side, pGina software must be installed on each Windows workstation. If you have a large number of workstations this would not be the best way to go about things.

One thing I definitely suggest is to upgrade the tired old version of OpenLDAP that Red Hat ships with RHEL4 to something more current.

I hope this helps...

-Matt