[lug] "Kernel panic:vfs:unable to mount root fs on 16:02"

[D. Stimits]

Chandrakiran Govindarajula wrote:
> 
>    Part 1.1Type: Plain Text (text/plain)

For some reason your email is being sent as an attachment, my version of
Netscape won't view plain text attachments inline (a good idea not to
for html and non-text).

I'm going to repaste part of it here, as non-attachment:
<quote>
partition check: 
hda:hda1 hda2 hda3 hda4 <hda5 hda6 hda7 >
autodetecting raid arrays
autorun....
............autorun done.
request-module[block-major-22];Root fs not mounted
VFS:cannot open root device 16:02
Kernel panic:vfs:unable to mount root fs on 16:02
</quote>

Block major 22 is support for /dev/hdc, any partition. I forget how to
interpret the 16:02, it is fairly simple though, I'm thinking "16" is
hexadecimal (which is 22 in decimal), and the 02 is probably the minor
number, meaning hdc2. Which in turn is a primary or extended partition
(if primary, it is used directly, if extended it contains a logical
partition which is the real target).

My *guess*, without knowing more, is that a module or other support is
required to read a filesystem on /dev/hdc2 or a logical partition within
/dev/hdc2. Has it ever worked? Is this a root partition? Some
motherboards do not detect or allow booting past the second hard drive,
but it seems that what it is missing is support to read what is there,
rather than missing the partition itself.

So that makes me think this is either an odd, non-ext2 partition,
without a module to support the filesystem type. The other alternative
is that this is the ROOT partition, and that the filesystem type is not
supported except by modules...and the modules are on that partition, so
it can't read it to find out how to read! Chicken and egg dilemma, which
came first? Well, if this is your root partition, you need an initial
ramdisk support, and an actual initial ramdisk with the module in it (or
else support compiled directly into the kernel). After it can find the
module for block-major-22, then you can probably see the partition. Oh,
and if this is not a root partition but a strange filesystem type, and
if you do actually have the module, perhaps it is looking for the module
by the wrong name? If it is looking for the wrong name, then
/etc/modules.conf should have an alias entry added to tell it the name
to look for support of block-major-22 as. That entry would have to be
there at the time of writing an initial ramdisk if this is a root
partition, so fixing the problem for a root partition means more than
just adding the entry of an alias.

D. Stimits, stimits at idcomm.com