alanef: > I am getting flooded by 'lost connection after UNKNOWN', I have search hard
Postfix logs the last SMTP valid command, or "unknown" if the last command was invalid. Apparently what you see are connections from home computers infected with malware that has some half-baked SMTP implementation. Postfix is built to handle such abuse, so you can ignore it. If this prevents you from receiving mail then you may want to look into Postfix's built-in zombie filter http://www.postfix.org/POSTSCREEN_README.html Wietse
