menu.lst changed after update 8.10

[Derko]

After Ubuntu 8.10 did some updates my menu.lst has been changed and now I cannot boot into Ubuntu.
I know how to edit menu.lst by booting from the live CD but I do not know the syntax.
I tried this:

root (hd0,5)
kernel /vmlinuz root=/dev/sda6

but this results eventually in

...
...
...
[0.920183] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)

I hope this is trivial.

Derko

[ajgreeny]

Do you have any idea what changes were made? Perhaps there is a backup of the original which you can use as a template for the new one. I am surprised there is a problem, however, unless it's just a case of a new kernel which needs a graphics driver installed before you can get the GUI up and running.

What exactly are your symptoms? I don't think a normal update would do anything unless a new kernel was installed, so the graphics driver is very likely. Try starting in recovery mode and choosing xfix at the menu which appears.

[muteXe]

My update added a load of new kernel options to the list, but it was just a case and commenting out all the ones i dont want. I normally just leave the latest kernel version, and its safe mode equivalent (and xp).

Not sure how it could screw anything major up.

[Derko]

It was just the automatic Ubuntu-update. I remember it asked something about the menu.lst and I think I chose something like "keep original menu.lst". Then it rebooted with above result.

Does anybody know how menu.lst can be rebuilt or editted by me because I think my Ubuntu-installation is OK but only my menu.lst is corrupt.

Derko

[ajgreeny]

If you run the Live Ubuntu CD and from that post the output of
sudo fdisk -l and
sudo blkid then mount the installed ubuntu partition and show us your current non-working /boot/grub/menu.lst, it should be possible to tell you what to change to get it working again.

[Derko]

ubuntu@ubuntu:~$ sudo fdisk -l

Disk /dev/sda: 120.0 GB, 120034123776 bytes
255 heads, 63 sectors/track, 14593 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x7ab852fc

Device Boot Start End Blocks Id System
/dev/sda1 * 1 5099 40957686 7 HPFS/NTFS
/dev/sda2 5100 14593 76260555 5 Extended
/dev/sda5 5100 5585 3903763+ 82 Linux swap / Solaris
/dev/sda6 5586 14593 72356728+ 83 Linux
ubuntu@ubuntu:~$ sudo blkid
/dev/sda5: UUID="e2b2210d-b9b1-4afa-9c2f-6866dc571a48" TYPE="swap"
/dev/sda6: UUID="2871f0e0-19e2-4ea7-8b8e-a42c84c6d224" SEC_TYPE="ext2" TYPE="ext3"
/dev/loop0: TYPE="squashfs"
ubuntu@ubuntu:~$

[kvarley]

My brother had exactly the same problem!

He managed to fix it using super grub disc.

gnu/linux > fix option

You can grab super grub disc here: http://www.supergrubdisk.org/index.php?pid=5

Hope this helps.

[ajgreeny]

What about your current /boot/grub/menu.lst? That would be very helpful as well. I agree it's worth trying supergrub, which I tend to forget, never having needed to use it.

[Derko]

Sorry, forgot to include menu.lst
Now i'm at work. Will do it this evening.

But maybe you can explain the menu.lst syntax

root (hd0,5)
kernel .....

What comes after 'kernel'. As I remember something with this UUID-code ?

Derko

[ajgreeny]

OK, here's a template from (8.04) to give you a clue.


title Ubuntu 8.04.2, kernel 2.6.24-23-generic
root (hd0,1)
kernel /boot/vmlinuz-2.6.24-23-generic root=UUID=6338bfe4-eb42-4fd9-a621-2320b27884f5 ro quiet splash
initrd /boot/initrd.img-2.6.24-23-generic
quiet