grub2 discover less hard drives and shows "no such device error"

[kismet-sl]

Dear All,

I have just installed Ubuntu 10.04 on my system which has the following hard drives setup:
- motherboard controller:
/dev/sda
/dev/sdb
- motherboard SATA Raid controller (configured in SATA mode)
/dev/sdc

I have installed linux on /dev/sdc2 boot I had to install the grub2 on /dev/sdb which is the one that was actually booting the system. (I found that, because at the beginning I installed grub2 on /dev/sda but it was not loaded at all during the bootstrap of the machine)

The result is that when the system boostrap it end up to "grub rescue>" shell reporting that


error: no such device: <UUID>

The strange part is that from the "grub rescue" only the ls command works, while help, dump, lsmod, or insmod return the message "Unkwon command"

On the "grub rescue" i found that ls report only


(hd0) (hd0,1) (hd1,1) (hd1,5) (fd0)

but the grub configuration states that the root is on (hd2,2) so it seems that the problem is that (hd2) the drive with the uuid shown by the error message is not recognize by grub, do you have any idea?

Thank you!

[dino99]

open a console then run:

sudo grub-mkconfig
sudo update-grub

look at this thread too: http://ubuntuforums.org/showthread.php?t=1574605

[kismet-sl]

I have done what you suggested by starting the system with Ubuntu Install CD in LiveCD mode, then I opened a console and I executed the following command:


sudo mkdir /mnt
sudo mount /dev/sdc2 /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
sudo chroot /mnt


Then from the chroot environment I executed the command that you suggested:


sudo grub-mkconfig
sudo update-grub


I rebooted but I received the same error message from grub2.


error: no such device: 96574346-f4cc-42a0-b7cf-a0f095a6b096

(exactly the uuid of /dev/sdc)

I think it is worth to note that my system has the following setup:
/dev/sdc 232.88G
/dev/sdc1 - extended
/dev/sdc5 - NTFS UUID=8678C11778C106C1

/dev/sda 232.88G
/dev/sda1 - NTFS, 58.89G UUID=4ED0BBD8D0BBC48D


/dev/sdb 189.92G
/dev/sdb1 - NTFS, 117.19G UUID=C4C41EADC41EA1AA
/dev/sdb2 - ext4, 27.94G UUID=96574346-f4cc-42a0-b7cf-a0f095a6b096
/dev/sdb6 - ext4, 42.88G UUID=cb7.....
/dev/sdb5 - swap, 2G

but the ls command (executed from the grub rescue shell) reports only


(hd0) (hd0,1) (hd1) (hd1,5) (fd0)


which I can hardly map to my actual system configuration.

I have also tried to execute (from the grub rescue shell) the commands


set root=(hd0,1)
chainloader +1

for booting up windows but it received the error unknown command "chainloader"

P.S.: I have notice that /dev/sdXY the X changes between reboot so I have perform grub-install on all the /dev/sdX

Thank you!