Oops grub go bye bye

TheCakeIsNaOH · February 24, 2019, 7:08pm

See here-

Table of Contents Intro Debian and Ubuntu Arch Fedora We’ve all been there. We’re dual booting and Windows does a major upgrade. Suddenly, without warning, in the quiet of night, we can no longer access our Linux partition. Or, maybe you’re not on Windows. Maybe you’re using Arch (btw…). You upgrade your OS after a week and, boom, SHTF. No more GRUB. Perhaps you’ve done what I did. You don’t have Windows on your computer. But you decided to use it for something and a VM isn’t cutting it. So, you install Windows on an ENTIRELY DIFFERENT HARD DRIVE and, still, despite your precautions, GRUB is gone -_-; What do you do? Do you really reinstall Linux, again, and lose your precious data? You made a ton of commits last night, but never pushed your changes! Never fear! Trusty Ubuntu is here to save the day! (you can use whatever live environment you want, I am using Ubuntu for ease of use and familiarity) If you use UEFI, do not use the first set of commands, scroll down please. Debian and Ubuntu family The live USB instructions are applicable to all of the distributions below. Create a live USB with Etcher, Rufus, dd, or whatever your poison. https://www.ubuntu.com/download/desktop After that, you’ll want to select “Try Ubuntu without installing” to load the live environment. Next, fire up the terminal. Find your drive with linux on it. lsblk -f works, as does gparted or parted -l Mount the root partition. For me, it was /dev/sda2 sudo mount /dev/sda2 /mnt Next, you need to mount components of the file system to /mnt: sudo mount --bind /dev /mnt/dev sudo mount --bind /dev/pts /mnt/dev/pts sudo mount --bind /proc /mnt/proc sudo mount --bind /sys /mnt/sys If you receive errors on the above, you may need to mount another partition. Next, chroot into /mnt: sudo chroot /mnt Run the following commands: grub-install /dev/sda grub-install --recheck /dev/sda u…