Fail2ban hasn’t been working for me, I still have people running brute force attacks on my Postfix server, so I though I’d rig up something myself. This consists of a bash script that identifies multiple failures and bans them, run on cron every 10 minutes. It checks for both smtp and pop/imap login failures. #!/bin/sh […]

There are various guides online for setting up Postfix as a backup (hold and forward) mail server which knows which accounts are valid on the primary (to prevent backscatter spam, so it only accepts emails for actual accounts that exist on the primary mail server). All of them are slightly different and none of them […]