iptables is a powerful tool to help configure access to various ports on your computer or server. It provides the level of control that makes it possible to configure what network traffic is permitted or denied to the system.
The main quirk about iptables is that, by default, the configurations for iptables will not persist after a reboot. After configuring your system’s iptables rules, there is one more important step that you must do in order to make sure the rules are still there after a reboot.
In this tutorial, you will see how to make iptables rules persistent after reboot on Ubuntu and CentOS-based systems.