13. Basic Fedora 31 Firewall Configuration with firewalld

A firewall is a vital component in protecting a computer system or network of computers from external attack (typically from an external source via an internet connection). Any computer connected directly to an internet connection must run a firewall to protect against malicious activity. Similarly, any internal network must have some form of firewall between it and an external internet connection.

All Linux distributions are provided with a firewall solution of some form. In the case of Fedora 31 this takes the form of a service named firewalld.

While the subject of firewall configuration can be complex, fortunately Fedora 31 provides command-line, web-based and graphical tools that ease the firewall configuration process. This chapter will introduce the basic concepts of firewalld and cover the steps necessary to configure a firewall using the tools provided with the operating system.