Chiming in... If you are going to have a secondary MX machine, then it should have knowledge of all local accounts on the primary MX machine, and this knowledge should be accessible even if the primary is down. That means some kind of periodic synchronization of user lists from the primary to the secondary. Be aware that there may be windows in which the secondary rejects a recipient the primary would have accepted, or vice-versa, but if your synchronization interval is small enough, it's probably an acceptable tradeoff.
md_check_against_smtp_server was *not* designed for a secondary to check against a primary. It was designed for people who use an Internet-facing MIMEDefang box as a front-end to relay to their real mail server. In this situation, the real mail server can reasonably be expected to be highly-available (and if it's down, then it's OK for the MIMEDefang box to tempfail.) Regards, David. _______________________________________________ NOTE: If there is a disclaimer or other legal boilerplate in the above message, it is NULL AND VOID. You may ignore it. Visit http://www.mimedefang.org and http://www.roaringpenguin.com MIMEDefang mailing list MIMEDefang@lists.roaringpenguin.com http://lists.roaringpenguin.com/mailman/listinfo/mimedefang
