Updating Grub 2 -
If you want to change your grub configuration (reorder, change, remove etc) - there are TWO steps
1. Make The Change
2. Update Grub
For example, If you want to change the selected OS to boot from (usually the first one is selected by default).
rohit@lenovo:~$ sudo gedit /etc/default/grub
rohit@lenovo:~$ sudo update-grub
Generating grub.cfg ...
The steps above, essentially means, I opened the grub file in a text editor, made changes and saved it. Then I ran update-grub to cement my changes. Done
