how to change ubuntu grub boot order

FREQUENTLY ASKED QUESTIONS  (Ubuntu)

Q: How to change grub boot order in Ubuntu linux?

If you installed other operating systems with Ubuntu linux, you may need to change the default booting OS from Ubuntu to other installed OS like Windows7, Win XP, etc.

click to enlarge

You must have a grub menu like  screenshot(left).
Here i am changing the default boot target from Ubuntu to windows7. As the screenshot, boot order number of windows7 is 4. (order counts from zero)

In command line mode edit the grub configuration file

user@ubuntu:~$ sudo vi /etc/default/grub

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As per the first grub screenshot, to change default boot to windows7 
Edit the line 
GRUB DEFAULT=4
#and save the file








After editing grub file run the below command to validate
user@ubuntu:~$ sudo update-grub
                         or
user@ubuntu:~$ sudo update-grub /boot/grub/grub.cfg


Reboot to verify new boot target 
user@ubuntu:~$ sudo reboot

LABELS: Debian, extra-tips, FAQ, Grub Boot loader, How-To, linux, Ubuntu