PGNd: > If fixed, what's intended by design -- milter before proxy-filter? > Or, vice versa?
Postfix implements multiple layers of defense to block mail: the order of these is postscreen, smtpd_mumble_restrictions, milter SMTP command inspection, smtpd_proxy_filter, header/body_checks, milter header/body inspection, content_filter. The order is fixed for practical reasons. If you want to know why, then you will have to learn this yourself from the way the system works internally. Wietse