To Drop IP in iptables
Port Specific:
iptables -A INPUT -p tcp -s xx.xx.xx.xx –dport {PORT} -j DROP
iptables -A INPUT -p tcp -s xx.xx.xx.xx –dport 80 -j DROP
/sbin/service iptables save
No Port Specified:
iptables -A INPUT -s xx.xx.xx.xx -j DROP
/sbin/service iptables save
Example:
/sbin/iptables -I INPUT -s {IP-HERE} -j DROP
/sbin/iptables -I INPUT -s 1.2.3.4 -j DROP
/sbin/service iptables save
To Allow IP in iptables
iptables -A INPUT -p tcp -s xx.xx.xx.xx –dport {PORT} -j DROP
iptables -A INPUT -s xx.xx.xx.xx -j ACCEPT
/sbin/service iptables save
Unblock / Delete an IP Address Listed in IPtables Tables
– To display line number along with other information, type the command below.
iptables -L INPUT -n –line-numbers
iptables -L OUTPUT -n –line-numbers
Search for the IP Address that you want to delete. Example 192.168.2.4
iptables -L INPUT -n –line-numbers | grep “192.168.2.4”
12056 DROP all — 192.168.2.4 0.0.0.0/0
2. IP address 192.168.2.4 is in line 12056 so we will use the command below to delete line 12056.
iptables -D INPUT 12056
/sbin/service iptables save
Other way to remove the IP is like this one.
iptables -D INPUT -s xx.xxx.xx.xx -j DROP
/sbin/service iptables save