grub-set-default

Grub-set-default is a command-line tool used in Linux systems to set the default operating system or boot entry for the GRUB bootloader.

1. GRUB is the default bootloader used in most Linux distributions to initiate the boot process and allow users to choose their desired operating system at startup.
2. Grub-set-default helps in changing the default operating system that GRUB loads when the system starts.
3. It is a part of the GRUB package and is typically found in the /usr/sbin directory.
4. To use grub-set-default, administrative privileges (root access) are usually required.
5. The syntax for using the command is: grub-set-default [entry_index].
6. The entry_index parameter represents the index number of the operating system or boot entry listed in the GRUB menu.
7. The index starts from 0, with the first entry being 0, the second being 1, and so on.
8. Grub-set-default sets the default entry by modifying the default line in the GRUB configuration file (/etc/default/grub).
9. After running grub-set-default, it is necessary to update the GRUB configuration using the update-grub command for the changes to take effect.
10. This command is particularly useful for dual-boot systems, allowing users to choose which operating system should be booted by default.