>> We planned on running multiple MTA, one by frontend (2), to get some >> redundancy. I'll keep the idea in mind, in case the frontend choke up. > we plan to run 4 mtas, 2 handling incoming traffic, 2 for outgoing > traffic, with ldap slaves on each mta. > the mtas will use these ldap slaves for mail routing, which leaves the > cyrus backend ldaps for user authentication.
That's exactly what I'm doing here. Almost every MTA and the cyrus servers have their own LDAP replica. I had some problems years ago when the central and only LDAP Master hung from time to time. Now, every service is configured to use it's local replica and another one as fallback. Enlarging the cachesizes in OpenLDAP has also helped alot. Simon