The introduction of Postfix's postscreen into edge mail-defense, particularly with a well thought out set of DNSBLs has fairly dramatically cut down on my spam rates.
Additional pre- & post-queue filtering downstream of postscreen is down to a easily manageable trickle. Prior to postscreen, fail2ban had been a key component of my basic anti-spam tooling. Looking at my (early) results, I'm considering simply dropping fail2ban from the mix. It seems resource utilization of postscreen is already quite low. Reading posts since the introduction of postscreen, I've not yet found any strong arguments for removing it or leaving it in. What current 'best practice' on list? With postscreen ON, still bothering with fail2ban? If yes, what particular case would postscreen be missing that fail2ban'd catch?
