Install grub manually to make disk bootable

Sebastien Devaux — Thu, 14 Aug 2014 14:24:00 +0200

Use this procedure to repair a broken boot of a system disk boot or to make a new restored system disk bootable. To run the procedure you need an already running linux. If not available, use a live CD or USB key. The disk to make bootable must already contain a partition with almost complete linux system: in particular drub binaries and /boot directory with kernel and grub configuration.

first ensure what is the partition containing the /boot directory. In the following it's considered to be /dev/sdb1. Check this partition has the bootable flag and add it if not (defaulty use fdisk to proceed).
mount the root partition, and special file system at the right place relatively to the future root partition mount point.

# mount /dev/sdb1 /mnt/
# mount -t proc none /mnt/proc
# mount -o bind /dev /mnt/dev
# mount -t sysfs sys /mnt/sys

start a chrooted shell into the future root file system and install grub from it.

# chroot /mnt/ /bin/bash
# update-grub
# /usr/sbin/grub-install --recheck --no-floppy /dev/sdb

terminate chroot shell and unmount partitions properly and the disk is ready to boot.

L'ardoise eduvax - Tag grub

Install grub manually to make disk bootable