Explain Linux boot process

Question 1

/etc/default/grub

Answer 1

“GRUB 2 is configured by editing either the /etc/default/grub file or the files in the /etc/grub.d directory. The files in the /etc/grub.d directory are “advanced files”

Question 2

/etc/grub2.cfg

Answer 2

“The primary configuration file for GRUB2 is the /boot/grub2/grub.cfg file. This file should never be edited directly, as it is created by the grub2-mkconfig command (see the “grub2-mkconfig” subsection in this chapter for more details).

The /etc/grub2.cfg file is just a symbolic link to the /boot/grub2/grub.cfg file.”

Question 3

/boot

Answer 3

“The /boot directory is the location where boot files are found. This includes the following”

Question 4

/boot/grub

Answer 4

“The /boot/grub directory is the location for traditional GRUB configuration files”

Question 5

mkinitrd

Answer 5

“This initramfs file is created by the mkinitrd command, which in turn calls the dracut utility”

Question 6

grub2-install

Answer 6

“Typically the bootloader is installed during the boot process, but it is possible that the bootloader could become corrupt and need to be reinstalled. To install the bootloader, execute the grub-install command and provide the device where you want to install GRUB”

Question 7

grub2-mkconfig

Answer 7

“Only used for GRUB2, grub2-mkconfig will generate GRUB2 configuration files from the user-editable files located in the /etc directory structure. This command converts data from the /etc/default/grub file and the files in the /etc/grub.d directory into the GRUB2 configuration file (either /boot/grub/grub.cfg or /boot/grub/menu.lst).”