Further reading
- netstat – The easy tutorial: https://openmaniak.com/netstat.php
- 4 ways to find which process is listening on a specific port: https://www.putorius.net/process-listening-on-port.html
- netstat versus ss Usagte Guide: https://computingforgeeks.com/netstat-vs-ss-usage-guide-linux/
- The official Nmap website: https://nmap.org/
- The GNU GRUB manual: https://www.gnu.org/software/grub/manual/grub/grub.html
- How to boot Ubuntu 18.04 into emergency and rescue mode (An alternate method that still works on Ubuntu 22.04.): https://linuxconfig.org/how-to-boot-ubuntu-18-04-into-emergency-and-rescue-mode
- How to see the GRUB boot menu on Ubuntu 18.04: https://askubuntu.com/questions/16042/how-to-get-to-the-grub-menu-at-boot-time