How do I find or check IP’s that are currently banned using iptables command in Linux? How do I verify that IP address 1.2.3.4 is banned or not in Linux?
The correct syntax to block an IP address under Linux using iptables is as follows:
/sbin/iptables -A INPUT -s BAN-IP-ADDRESS -j DROP /sbin/iptables -A INPUT -s BAN-IP-ADDRESS/MASK -j DROP |
Open a command-line terminal (select Applications > Accessories > Terminal), or login to remote server using the ssh and then type the following command block an ip address 1.2.3.4 as follows:# /sbin/iptables -A INPUT -s 65.55.44.100 -j DROP
To view blocked IP address, enter:# iptables -L INPUT -v -n
OR# iptables -L INPUT -v -n | less
Task: Check Banned IP’s Linux
Use the grep command as follows to verify that an IP address 1.2.3.4 is blocked or not:# iptables -L INPUT -v -n | grep "1.2.3.4"
How Do I Delete or Unblock IP Address 1.2.3.4?
Use the following syntax to delete or unblock an IP address under Linux, enter:# iptables -D INPUT -s 1.2.3.4 -j DROP
Finally, make sure you save the firewall:# service iptables save
