How to setup a UFW firewall on Ubuntu 18.04 LTS server

UFW is an acronym for an uncomplicated firewall. Securing a network with the uncomplicated firewall is super easy. The Ubuntu Linux comes with packet filtering called Netfilter. The iptables frontend command used to manage netfilter. However, ufw provide easy to use frontend for netfilter, and it is one of the most popular among Ubuntu sysadmins and developers. This page shows how to set up and secure your Ubuntu 18.04 LTS server with ufw.