My next step for my mail system revamp is to add fail2ban. I've read up on how to configure it for Postfix and I think I'm up to speed. I have a few things which I have ideas about configuring for, so if anyone has experiences with these, or warnings against using them, I would appreciate the feedback.
1. I get hit with small floods of "Sender address rejected: Domain not found" from the same sender. 2. People attempting to actually auth against smtpd with a username and password 3. Spam floods, mostly from Chinese addresses, with the "lost connection after AUTH from unknown" dance. Doug
