Summary

In this chapter, we took a look at the boot process. We then discussed init and systemd. We used the pstree command and saw the first process that is loaded. We also used the ps command to identify the process number. We then looked at the boot messages that would normally scroll across the screen using the dmesg command. The messages displayed offer us hints as to what was loaded upon boot up. Furthermore, we can use the messages displayed to assist us whilst troubleshooting. Next, we covered GRUB and GRUB2, looking at the structure of GRUB, particularly /boot/grub/grub/conf. We looked at adding a custom menu entry in GRUB. We then explored interacting with GRUB in real time at the boot menu. After that, we looked at GRUB2, focusing on the structure of /boot/grub/grub.cfg. In addition, we looked into the other locations that play a role in the GRUB2 configuration: the...