Just the commands I always need to look up, because I forgot again...

• Overview over fail2ban status and jails

fail2ban-client status

• See which e.g. IPs are banned for sshd jail

fail2ban-client status sshd

• Unban an IP from sshd jail

fail2ban-client set sshd unbanip IPADDRESSHERE

• See which systems are actually banned

zgrep 'Ban' /var/log/fail2ban.log*