Introduction and basic usages of iptables under Unix/Linux

* What is iptables in Linux ?  Iptables is a rule based firewall system and is normally pre-installed on a Unix operating system which is controlling the incoming and outgoing packets. Basic structure of iptables The structure for the iptables is like, tables which has Chains and the chains which contains Rules. Tables —> Chains […]

Iptables commands .

  #!/bin/sh#File: /etc/rc.d/rc.firewall# At once log and drop any known abusive IPsiptables -A INPUT -p tcp -s 87.118.104.44 -m limit –limit 1/minute –limit-burst 10 -j LOG –log-prefix “[DROPPED_NODE]“ –log-level 4iptables -A INPUT -p tcp -s 87.118.104.44 -j DROP# Allow fr?m ?n? t? ?n? ?n 127.0.0.1/32iptables -A INPUT -s 127.0.0.1/32 -j ACCEPTiptables -A OUTPUT -s 127.0.0.1/32 -j […]