Just wondering what authentication software you were looking at. These days, I've found FreeIPA to be surprisingly feature rich (and bundled with the OS!). -LDAP -Kerberos -Certificates -Multi-Master replication -Password policies All built in! There is a Samba hook too, but I'm not sure that is relevant here.... The FreeIPA devs are also very nice people who've been receptive to feature requests. Mostly I'm just curious what people are thinking ..... Pat -- Pat Riehecky Scientific Linux developer http://www.scientificlinux.org/