disk mduuid not found

[Tom H]

On Fri, Feb 15, 2013 at 11:11 AM, Michael Hipp <michael at redmule.com> wrote:
>
> I'm trying to install 12.04.2 to a small LAN server for a client.
> Configuration:
>
>   md0 /dev/sda1 /dev/sdb1  / (root, including /boot)
>   md1 /dev/sda2 /dev/sdb2  swap
>   md2 /dev/sda3 /dev/sdb3  /mnt/data
>
> All are software RAID1 with 2 devices no failovers. Install went fine, but
> upon bootup I'm confronted with:
>
>   error: disk 'mduuid/{hex uuid stuff}' not found
>   grub rescue>

You can boot from the "grub rescue" prompt and re-install grub.

Run "ls" and "set".

"ls" will list the disks and partitions that grub sees.

"set" will list, among other things, "root=..." and "prefix..."

For "/" and "/boot" on the same partition, reset them with "set
root=(hd0,msdosX)" where "/" is "/dev/sdaX" and "set
prefix=(hd0,msdosX)/boot/grub" (replace "msdosX" with "gptX" if the
disk has a gpt label).

For "/" and "/boot" on different partitions, reset them with "set
root=(hd0,msdosX)" where "/boot" is "/dev/sdaX" and "set
prefix=(hd0,msdosX)/grub" (replace "msdosX" with "gptX" if the disk
has a gpt label).

Once "root=..." and "prefix..." are reset, run "insmod normal" or
"insmod normal.mod" (I've forgotten which one's correct in rescue
mode, sorry).

Loading the normal module'll allow you to boot with commands similar
to a menuentry stanza.

For "/" and "/boot" on the same partition:
grub> linux /boot/vmlinuz-... root=UUID=uuid_of_root_device ro
grub> initrd /boot/initrd-...
grub> boot

For "/" and "/boot" on different partitions:
grub> linux /vmlinuz-... root=UUID=uuid_of_root_device ro
grub> initrd /initrd-...
grub> boot