Ubuntu's Uncomplicated Firewall, or ufw, is a handy front-end for either iptables or nftables. As the name suggests, ufw vastly simplifies the process of setting up a basic Linux firewall. You can also set up more complex firewall configurations, but Ubuntu doesn't do a good job of showing you how to do that. Note that ufw is also available on Debian and Debian-based Linux distros as well as on Ubuntu and Ubuntu-based Linux distros.
Enjoy this Linux tutorial from the BeginLinux Guru!
Purchase links for my books:
Mastering Linux Security and Hardening
Packt Publishing link:
https://www.packtpub.com/product/mastering-linux-security-and-hardening-third-edition/9781837630516
Amazon link:
https://amzn.to/3ZdIR7Y
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Linux Service Management Made Easy with systemd
Packt Publishing link:
https://www.packtpub.com/product/linux-service-management-made-easy-with-systemd/9781801811644
Amazon link:
https://www.amazon.com/Linux-Service-Management-Made-systemd/dp/1801811644/