> And the most effective countermeasure to spam originating from devices > on the LAN has nothing to do with Postfix. As most spamware in the wild > today still attempts to send direct-to-MX, simply creating a TCP 25 > egress filter at your edge router/firewall will give the best bang for > the buck. This simply means creating a rule to drop all outbound TCP 25 > connections except those originating from the IP of your Postfix MTA.
I don't understand. Situation: A real user using browser connect to squirrelmail and send a mail. It's ok. But if this user create a mail bomb using squirrelmail how way to spam I can have this problem. If a drop port 25, user can send any mail. Or tell me what I don't understand. Thanks!
