Linux Firewall Configuration

I recently installed Ubuntu 16.04 on several of my machines. In the process of setting up, I decided to enable the Uncomplicated FireWall (UFW).

Here are some tutorials from DigitalOcean describing the basics of UFW:

https://www.digitalocean.com/community/tutorials/initial-server-setup-with-ubuntu-16-04

https://www.digitalocean.com/community/tutorials/how-to-set-up-a-firewall-with-ufw-on-ubuntu-16-04

https://www.digitalocean.com/community/tutorials/ufw-essentials-common-firewall-rules-and-commands