Comment 21 for bug 756564

Followed these steps from mitchelln and http://karuppuswamy.com/wordpress/2010/06/02/how-to-chroot-to-ubuntu-using-live-cd-to-fix-grub-rescue-prompt/ to repair my natty RAID1 upgrade:

# Boot from LiveCD
# Made a directory to mount the root filesystem to
sudo mkdir /media/internal
# -- Going to chroot into our RAID1 system
# Notice the following is not the whole RAID drive nor the swap, just where the root filesystem exists (specific to my system)
sudo mount /dev/mapper/[partition where the root filesystem is on the RAID] /media/internal
# i.e. sudo mount /dev/mapper/isw_[some-id]_RAID1p5 /media/internal
sudo mount --bind /dev /media/internal/dev
sudo mount --bind /proc /media/internal/proc
sudo mount --bind /sys /media/internal/sys
sudo chroot /media/internal
# May not be there
apt-get purge dmraid
apt-get install dmraid
# I believe here it is the whole RAID disk, not just the partition
grub-install /dev/mapper/isw_[some-id]_RAID1
update-grub2
reboot

That was it. Unfortunately, I do have an error that appears on the splash screen relating to skip the mounting process or the similar, but once skipped my login screen came up and system is operational.