FW: Re: RedHat AS 2.1 (kernel panic)

[richb at pioneer.ci.net (Rich Braun)]

Jerry Feldman <gaf at blu.org> suggested thus...
> It sounds like Grub is pointing to the wrong partition.
> Run a rescue disk, and check the partitions, then mount the partition
> that has /boot and take a look at the /boot/grub/menu.lst (or grub.conf).

Ah, so Red Hat users share at least a little of my SuSE pain.  ;-)  Anyway
Jerry when you posted that, I got reminded of one of the failed experiments
that I tried after finishing my SuSE-10 installation:  installing GRUB2.

>From what I can tell, GRUB was abandoned by its original author and picked up
by an assortment of GNU hackers who opted for a total rewrite.  What I learned
was that (a) the rewrite isn't really done yet, and (b) the documentation
hasn't even been started.

Being a bold QA tester in the face of undocumented software, I went ahead and
ran a compile and installation of GRUB2.  (Actually, version 1.91.)  When I
tried to use it, the error was something about probefs not finding the
filesystem, which I quickly concluded was due to my /boot partition being
unsupported (I'd made it reiserfs instead of ext3 or whatever GRUB2 wanted). 
At that point I abandoned the project instead of going down a binary-tree path
of workarounds in the absence of documentation, given that my goal was to make
the system boot off either drive of software RAID and GRUB2's authors make no
claims whether this is supported.

After reverting to the previous GRUB, the next time I typed reboot remotely to
the system, it didn't come up.  Going over to the console, I found that
instead of loading a kernel, it gave me a GRUB command-line prompt.

Why am I wasting y'all's time with this rambling post?  Because it might just
prove helpful if you run into the same situation in the future.  My attempts
to google a solution failed, and it took me something like 15 or 20 minutes of
GRUB recompile/reinstallation to discover what had happened.

Bottom line:  if you get dumped at the GRUB command-line prompt instead of
seeing a kernel, your menu.lst file is probably blown away.  To boot the
system, you will either have to remember what commands to type, e.g.

  kernel (hd0,0)/vmlinuz
  initrd (hd0,0)/initrd
  boot

or dig out your installation CD and tell it to boot your root fs.  Once you've
done that, restore /boot/grub/menu.lst to its original state.  (You did take
my advice about backups, right?  You do have an rsync'ed copy of /boot, right?
;-)

I *think* what happened was an errant 'make install' command issued within the
grub2 installation kit must've cleared my grub directory.

-rich