An overview of iptables
As I’ve mentioned, iptables is one of two command-line utilities that we can currently use to directly manage netfilter. It was originally introduced as a feature of Linux kernel version 2.6, so it’s been around for a long time. With iptables, you do have a few advantages:
- It’s been around long enough that most Linux admins already know how to use it.
- It’s easy to use iptables commands in shell scripts to create your own custom firewall configuration.
- It has great flexibility in that you can use it to set up a simple port filter, a router, or a virtual private network.
- It still comes pre-installed on some Linux distros, although it’s rapidly getting replaced by nftables.
- It’s very well documented and has free-of-charge, book-length tutorials available on the Internet.
However, as you might know, there are also a few disadvantages:
- IPv4 and IPv6 each require their...