Only the Ubuntu virtual machine is needed for this chapter. If you have never updated your machine, now might be a good time! The sudo apt update && sudo apt upgrade -y command upgrades your machine with all tools completely. If you choose to do this, make sure that you reboot your machine so that upgraded kernels are loaded. On Ubuntu, if the /var/log/reboot-required file is present, you can be sure a reboot is, well, required.
All scripts for this chapter can be found on GitHub: https://github.com/PacktPublishing/Learn-Linux-Shell-Scripting-Fundamentals-of-Bash-4.4/tree/master/Chapter09.
