What is iptables?
A simple wiki definition goes as “iptables is a user-space application program that allows a system administrator to configure the tables provided by the Linux kernel firewall (implemented as different Netfilter modules) and the chains and rules it stores.”
It is a tool that allows sysadmins to manipulate linux kernel firewall for security. I have used iptables to secure webserver from any anomaliies that may occur from intruders.
Before proceeding to the iptables firewall, Please follow the basic server configuration which consists of basic security configs.