The Linux boot process follows these stages:
Boot issues can occur at any stage.
Typical Linux boot issues include:
Reboot the system and access the GRUB menu:
This allows kernel selection and recovery options.
Select Advanced options for Linux and choose a recovery mode kernel.
Recovery mode provides a minimal environment for troubleshooting.
Common recovery options include:
Run filesystem checks on the root partition.
fsck -f /dev/sda1
Reinstall GRUB if the system fails to boot.
Mount root filesystem:
mount /dev/sda1 /mnt
Reinstall GRUB:
grub-install /dev/sda
update-grub
Edit GRUB entries temporarily to bypass errors.
At GRUB menu:
equiet splash)Ctrl + X to bootIf the root password is forgotten:
Boot into recovery mode
Select root – Drop to root shell
Remount filesystem as read-write
mount -o remount,rw /
Change password:
passwd root
Fix incomplete or broken package installations.
dpkg --configure -a
apt --fix-broken install
Exit recovery mode and reboot.
reboot
If recovery mode fails:
Linux recovery mode provides powerful tools to diagnose and fix boot issues. Understanding the boot process and recovery options allows safe system repair without reinstalling the OS.