[Tfug] Debian unable to mount root fs after an update/upgrade

[Christopher Robbins]

On 1/24/07, Glen Pfeiffer <glen at thepfeiffers.net> wrote:

<snip>

While the upgrade was executing, it asked me about replacing my
> kernel image (iirc) and said that if I am not 100% sure that I
> know what I am doing I should cancel, otherwise my system may not
> boot afterward. So I canceled that action, but it continued the
> rest of the upgrade without errors.
>
> I have not done anything to troubleshoot, because I have never
> encountered a failure to boot like this. Here is the last part of
> the boot messages:
>
> RamDisk: Couldn't find valid RAM disk image starting at 0.
> VFS: Cannot open root device "301" or unknown-block(3,1)
> Please append a correct "root=" boot option.
> Kernel panic - not syncing: VFS: Unable to mount root fs on
>    unknown-block(3,1)


</snip>

Well, you're not totally SOL :)

The error is telling you that it can't mount your root filesystem, resulting
in the kernel panic.  This usually means that there's no driver installed
for your filesystem.  It appears as if the
kernel upgrade that you didn't want to happen may have happened anyway.

There are two ways to go about this fix, and the easiest one is -

1.)  Get a livecd (Knoppix/Ubuntu/Damn Small) and run it
2.)  Mount your hard drive, and go to /usr/src/
3.)  Find the OLDER version of the kernel (the one with the older version #,
or the one under /usr/src/linux)
4.)  Change the grub config (assuming you're using grub, under
/boot/grub/menu.lst) to point to the old version
5.)  Reboot into your old setup!

Let me know how this works.  Hope it helps

-Chris



-- 
Chris Robbins
Systems Programmer
Department of English - University of Arizona
http://www.homerengineeringcorp.net