ConfigServer Community Forum

I have some rules set up in CSF to block unwanted login attempts to SMTP.
But apparently my setup blocks also the reception/delivery of mail from GB.

CC_DENY_PORTS = GB, plus a lot more of country codes
CC_DENY_PORTS_TCP = 25,465,587
CC_DENY_PORTS_UDP = 20,21,53

Perhaps my understanding of how a server works is incorrect.

I also enabled Enable login failure detection of pop3 connections and Enable login failure detection of imap connections

Please advice.

What you're attempting is not possible as SMTP authentication takes place over port 25 which is the port over which email is relayed.

Ok, thanks. Will have to trust the login failure detection then.
I suspected my setup was faulty, thanks for confirming.