[cbj4074]

Given that this has become the authoritative thread on this subject, I thought I'd add an example, for my own reference, if no one else's.

To unban an IP address manually, it is necessary to know the chain name and the rule number. As suggested elsewhere in this thread, the following command can be used to acquire this information:

# iptables -L --line-numbers

The relevant bits are at the end of the output. Here is an example chain with attendant rules:

Chain fail2ban-ssh (1 references)
num  target     prot opt source               destination
1    DROP       all  --  204.110.13.107       anywhere
2    DROP       all  --  1.234.20.21          anywhere
3    DROP       all  --  gw-tair-rp.rel.com.ua  anywhere
4    RETURN     all  --  anywhere             anywhere

In this example, three (3) IP addresses have been banned via the SSH jail (these are the DROP rules).

To unban the IP address 1.234.20.21, the command would be:

# iptables -D fail2ban-ssh 2

Don't forget that if fail2ban is restarted after this change to iptables, there is the potential for the same IP address to be re-banned. The reason for this is discussed earlier in this thread.

Good luck!