Seeking central user management software [closed]
Solution 1:
389 Directory Server / RedHat Directory server - as LDAP database backend. Standard Netscape LDAP. Fast, secure, flexible.
FreeIPA / RedHat IPA - for Identity, Policy and Audit (requires/installs 389/RH DS too). Will use kerberos and identify services via pam names. Centralized, smart, easy, secure.
p.s. Use RHEL 6 or Fedora 17 as server