marc perkel vrvaperkelcom thomas raef wrote good morning everyone im charge reducing spam customer site already spamassassin saupdate weeklyexecuted id like implement bogus mx filtering spam dont know correct name bogus mx mean setting low priority mx record points nonsmtp server id like know firsthand experience two questions 1 caused lost mail issue client complaints know every half decent mail server try mx real life often received complaints valid senders 2 reduced significantly spam id like know worth little trouble setup verifying question 1 thank time tom replied isnt marc perkel working im sorry messed name think im correct may want search archives information marc perkel see answers questions marc thats please flame directly sorry thomas j raef pzmclebasedsecuritycom yes name right front end spam filtering service currently filtering spam 2500 domains im using bogus mx records 2 years tell lose good email using bogus high numbered low priority mx records either leave port 25 closed return 421 error case want count hits log file see significant reduction spam bot spam get rid huge amount spam cut server load significantly spam longer goes spam assassin speeds processing good email way works spambot hit low priority mx records nothing happens move spambots dont retry 100 accurate blocks false positives using fact recommend using several low priority mx records increase effect taken idea several steps addition tracking hits low priority mx also monitor connection issues quit close spambots dont issue quit spambot hits bogus mx gets 421 error doesnt issue quit commits sins make blacklist currently tracking million spambot ip addresses hit servers last 4 days result tricks managed block 100 spambot spam little spam gets mostly yahoo hotmail gmail spam spamassassin takes care bottom line works simple side thu 07 aug 2008 013522 0800 ot bogus mx opinions yes works