Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I've been messing around with a cheap PC lately and now I have some questions about GRUB; what exactly does Ubuntu do with GRUB during a new install? Several times I've modified my partitions (moved the Linux partition left - namely) and not been able to get GRUB back and working. I've read online about both "grub" and "grub-install" from a Ubuntu Live CD, but can never manage to recover my computer to a working state.

Several times I've just wiped a partition and did a new install of Ubuntu on it just to get GRUB back to where I can boot ALL of my partitions.

So, I'd like to know, how can I accomplish that WITHOUT going through the entire install process?

share|improve this question

To my recollection, Ubuntu uses GRUB2, not GRUB (now, GRUB Legacy) - this might help your search for answers. The way I would go about making my system bootable again after shuffling partitions around (presumably, using something like PartitionMagic) is to boot from a LiveCD, get my Linux partitions mounted, then chroot into the Linux system. From there, make a backup copy of your GRUB2 configuration, then run

grub-mkconfig -o /boot/grub/grub.cfg

That should get you back up and running.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.