Which OS's grub configuration should I edit to change default boot order?
I have two OSes installed on two partitions of my (slightly old)computer: PeppermintOS (on /dev/sda1) and antiX (on /dev/sda2). When I turn my computer on, the GRUB menu defaults to antiX after timing out. I want to change that to Peppermint. I saw this post which gives a good answer on how to change the default boot – by modifying /etc/default/grub and then running sudo grub-update. But I still have one question:
If both of my OS’s have their own grub binaries and their respective configurations – Peppermint with its own /etc/default/grub in /dev/sda1 and antiX with its own /etc/default/grub in /dev/sda2, then which of these should I edit in order to get the desired results?
What I am having trouble understanding I suppose is how an OS specific grub install can be configured to serve the needs of the overall boot process before that particular OS has even been loaded.
Most likely your actual GRUB configuration belongs to the OS you installed the last however if you even ran grub-install in any of them, then the one where you last ran this command is again the one you should edit.
In a perfect world you should have a single separate /boot partition with a single GRUB configuration but considering how the Linux distros lack standardization that’s not always easily achievable.