Re: Grrrrrub2 again!!

[Tom H <tomh0665@gmail.com>]

On Thu, Jun 17, 2010 at 10:26 AM, Thierry Chatelet <tchatelet@free.fr> wrote:
> I did a new squeeze install on a desktop with dual boot, and install grub 2.
> System boot fine in debian, but $W was not present. No problem, I had this
> problem before and a simple update-grub solved it. But this time I got an
> error message:
> usr sbin grub-probe error cannot find a device for / (is /dev mounted)
> I am 'googling for about 10 hours now, but no luck.
> I purged and reinstall grub, still got the error, then performed a :
> grub-install /dev/sdb which went OK, but still update-grub gave the error.
> here is /boot/grub/device.map:
> (hd0)   /dev/hda
> (hd1)   /dev/sda
> (hd2)   /dev/sdb
>
> hd0 must be the dvd drive, hd1  the HD with $W,  hd2 the HD with squeeze on.
> It is split this way:
> dev/sb1 /boot
> dev/sdb1  a LVM
>
> df -k gives
> /dev/dm-0               /
> /dev/sdb1               /boot
> /dev/dm-5               /home
> /dev/dm-4               /tmp
> /dev/dm-1               /usr
> /dev/dm-2               /var

Your device.map must be incorrect.

Create another as root
grub-mkdevicemap --no-floppy --device-map=/root/device.map

Then test grub-probe
grub-probe --device-map=/root/device.map --target=drive --device /dev/sb
grub-probe --device-map=/root/device.map --target=drive --device /dev/sdb1
grub-probe --device-map=/root/device.map --target=drive /
grub-probe --device-map=/root/device.map --target=drive /boot
grub-probe --device-map=/root/device.map --target=device /
grub-probe --device-map=/root/device.map --target=device /boot

The first four should output the grub drives and the last two the dev devices.

I think that you could also delete /boot/grub/device.map (or move it
out of /boot/grub) and run the grub-probes without
"--device-map=/root/device.map".