# Old stupid way
sudo iptables -L -n | awk '$1=="REJECT" && $4!="0.0.0.0/0" {print $4}'
fail2ban-client status
fail2ban-client status dovecot-iredmail
fail2ban-client set dovecot-iredmail unbanip 46.161.106.162

# Restart service
service fail2ban restart

# Unban all in 10 seconds
fail2ban-client set dovecot-iredmail bantime 10
fail2ban-client set postfix-iredmail bantime 10
fail2ban-client set roundcube-iredmail bantime 10
fail2ban-client set sshd bantime 10
fail2ban-client set sshd-ddos bantime 10