I wandered into a company that has a lot of data centers and servers. However, the methods of authentication are all over the place. There are several AD instances (different forests), LDAP servers and even some systems that use local accounts. I'm trying to think of a way to centralize this so that you can use one authentication mechanism, sort of like RADIUS that is understood by Linux, Windows and network, and then pass it on to the directory on the backend.
But with so many different directories is this sort of thing possible or do I have to deploy one per DC?