Just as regular visitors reach our server every day, so do others with more nefarious intentions. It is simply not reasonable to run an online service without some layer of protection. To protect against some of these attacks, Ubuntu ships with ufw (Uncomplicated Firewall). This is a tool designed to make Ubuntu firewall management as easy and user-friendly as possible. Specifically, ufw provides a cleaner interface for the core firewall tools netfilter and iptables, which, while robust, can be challenging to master.