Hello, Debian 8 server with ISPConfig 3 latest apache. I see lots of IPs and domains that i have never heard of in the mail warning log like the below. Is there a way to ban those IPs with fail2ban or any other methods?
These are bots that probably try out passwords. Fail2ban should ban them if they reach a certain amount of tries from the same IP. If a new IP is used for each try, then it is not easy to ban them.
Thanks Till for the quick response, It seems to be a new IP for each trial. How could you make the mail to not receive lots of spam, the mail will be delivered and marked as spam is there a way to filter those and not deliver them?