Fail2ban and Denyhosts
If you are using fail2ban to protect your computer against intruders and you accidentally bans one of your own IP addresses while experimenting with a setup use these commands to get the banned IP out of the ban again:
$] fail2ban-client status $] fail2ban-client set <jail listed by the above command, e.g. sshd> unbanip <the banned IP address>
Sometimes the IP address remains in the IPtables. Find it using these commands:
$] iptables -L --line-numbers|less
look for your IP address and note the filter, e.g. INPUT, and the line number.
Remove it from IPtables using this command:
$] iptables -D <the chain to delete from, e.g. INPUT> <the line number found above>
If you also use denyhosts to keep intruders out of your box and the IP address is in /etc/hosts.deny edit all the files in /var/lib/denyhosts/* and remove the denied IP addresse as well as /etc/hosts.deny - but after you have stopped denyhosts using
$] systemmctl stop denyhosts.service.
Remember to restart after editing.