假設以下是已經被 ban 的 iptables 清單

iptables --list

Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
f2b-sshd   tcp  --  anywhere             anywhere             multiport dports ssh
f2b-sshd   tcp  --  anywhere             anywhere             multiport dports ssh
f2b-sshd   tcp  --  anywhere             anywhere             multiport dports ssh
f2b-sshd   tcp  --  anywhere             anywhere             multiport dports ssh

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         

Chain f2b-sshd (4 references)
target     prot opt source               destination         
REJECT     all  --  112.11.11.11        anywhere             reject-with icmp-port-unreachable
RETURN     all  --  anywhere             anywhere            
RETURN     all  --  anywhere             anywhere            
RETURN     all  --  anywhere             anywhere            
RETURN     all  --  anywhere             anywhere    

#删除在f2b-sshd中的第一条
iptables -D f2b-sshd 1

iptables --list
iptables-save

重新載入讓設定生效

service fail2ban reload