This guide will show you how to upgrade from one version of Ubuntu to the next (20.04 to 22.04, in this example), as well as the services that will prompt for action along the way.
Molly-Guard is a utility for Debian/Ubuntu systems that will prevent accidental remote shutdowns or reboots. This overview will explain how to get it up and running.
ModSecurity is an open-source web application firewall, and although it was originally developed for Apache, it can now sit in front of NGINX and even IIS web servers.