Re: boot failure "mount: mounting /dev/sda1 on /root failed: no such device"

[Andrew Reid <reidac@bellatlantic.net>]

On Monday 13 July 2009 21:13:16 Kelly Clowers wrote:
> On Mon, Jul 13, 2009 at 17:52, Kelly Clowers<kelly.clowers@gmail.com> wrote:
> > On Mon, Jul 13, 2009 at 16:38, Andrew Reid<reidac@bellatlantic.net> wrote:

> >>  The other way to investigate the initramfs, incidentally,
> >> is to just unpack it somehwere -- it's a cpio archive, you
> >> can google for instructions.
> >
> > Also good to know.
>
> Going to try this now, since break= does not seem to work for
> some reason...

  That strikes me as an Important Clue, although I'm not 
sure what to make of it.  Are you *sure* you're running an
initramfs?  ("Is it plugged in?")  Does your bootloader know
you want an initramfs?  How did you get the bootloader on
to the disk?  It's not part of the filesystem, so it didn't
come on with the restore-from-backup unless you used "dd"
to image it.  For grub, you have to do a "grub-install"
incantation.

  Anyways, assuming you *are* using an initramfs, there are
other predefined breakpoints -- they are:
  top, modules, premount, mount, bottom, init.
  
  You might try "break=top", that drops into the busybox shell
immediately after the initrd is unpacked, before running any
scripts at all.  It's also before modules are loaded, so it 
wouldn't be a huge surprise if the disks are missing at that
point, but at least you could check the integrity if your
initramfs environment, and run some stuff manually, maybe.

  "modules" breaks before any modules are loaded.

  "premount" is the default, and it'll break here if you
just provide a "break" kernel argument, with no value.

  Posting to the list, because this info about initramfs
breakpoints should be in more places.

  				-- A.
-- 
Andrew Reid / reidac@bellatlantic.net