16.9 Summary
Any computer system that is connected to other systems, either via an internal network or through an internet connection should implement some form of firewall to mitigate the risk of attack. The Uncomplicated Firewall provided with Ubuntu provides a simple yet effective firewall that allows basic rules to be defined either using the command-line or the graphical gufw tool. This chapter has outlined the basics of enabling the firewall and configuring firewall rules.