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I installed a second Linux distro recently which replaced the old grub that was already in place with its own fresh installation. I would like keep using the grub loader from the first OS, Ubuntu.

Braiam
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Nicolas Martel
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  • Why you want to do this? – Braiam Sep 11 '14 at 00:11
  • The second Linux installation stopped working and I wish to install Arch Linux in a new partition, until I free up the rest of the partitions. I have had trouble getting the Arch Linux live CD to boot from my USB key so I am trying to use grml-rescueboot to boot from the iso. Since the current boot loader is set to the second Linux installation, any change I make to the boot loader right now is useless until I can set it to use this grub. Sorry, lengthy comment – Nicolas Martel Sep 11 '14 at 00:15

1 Answers1

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First boot into the Ubuntu version that you want to want to use the grub loader from.

After that run:

sudo grub-install /dev/sda

replacing sda with the harddrive your BIOS uses as default boot device.

You probably want to run sudo update-grub as well, so your Ubuntu installation scans the available boot options and adds the second distro.

There are two things to keep in mind:

  1. If you get a kernel-upgrade after booting your new distro, that will not show up until update-grub has run on your old Ubuntu.
  2. If your new distro is on btrfs with subvolumes, and your Ubuntu doesn't know how to interpret btrfs partitions with subvolumes then the new distro will not show up in the grub boot options unless you update find-btrfs in /etc/grub.d to handle that.
Anthon
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  • How do you list which boot-loader the BIOS currently uses? – Ini Dec 24 '18 at 23:29
  • That statement is years old and I forgot to delete it in the meantime. There were a ton of things that disturbed me about stackoverflow in the past. I do not want to go into details. Anyway that statement from me is years old and I removed it. Thank you for pointing that out. – Ini Dec 25 '18 at 15:11