Find code and diagrams at: https://www.EliTheComputerGuy.com/ UFW is a simple firewall application that is included with Ubuntu nd can be installed on other distributions of Linux. Note: For the demonstrations to work you may need to change settings or hardware configurations within your virtualization software. I had to connect my host machine to a hard word connection for Rules for specific IP Addresses to work. sudo ufw status – shows current status of ufw sudo ufw enable – Enables ufw firewall By default ALL incoming traffic is blocked sudo ufw disable – Disables ufw sudo ufw status verbose – Shows all Rules currently configured for ufw sudo ufw allow 21 – Allows specific port sudo ufw allow ssh – Allows ports for a specific service sudo ufw status numbered – Shows rules in numbered order so that you can delete specific rules sudo ufw delete 1 – Deletes rule based on number sudo ufw allow from 192.168.1.2 – Allows traffic from a specific IP address to all ports sudo ufw allow from 192.168.1.0/24 – Allows traffic from a subnet to all ports sudo ufw allow from 192.168.1.2 to any port 22 – Allows traffic from a specific IP address to a specific port sudo ufw allow from 192.168.1.0/24 to any port 22 – Allows traffic from a subnet to a specific port sudo ufw reset – Deletes all rules and disables ufw