[PLUG] Question on Grub and fixing the MBR

[Michael C. Robinson]

On Tue, 2010-10-12 at 21:47 -0700, logical american wrote:
> I tried installing Ubuntu 10.10 maverick edition on an old system, but 
> ran into trouble with the MBR and grub
> 
> I get the infamous grub error 17 which means that it cannot find the 
> partition.
> 
> I have 4 disks, 2 scsi and 2 ide:
> 
> sda is ide 40 Gb   /home
> sdb is ide 120 Gb /boot /swap /all others /backup
> sdc is scsi 38 Gb /spare
> sdd is scsi 18 Gb /dos /win98 /winbck
> 
> I tried running "grub-install /dev/sdb" command while running the Ubuntu 
> CD live and that took.  I did set the boot flag on sdb3 partition (and 
> sdd2).
> 
> But when I tried to run "update-grub > grub.cfg in the /boot/grub folder 
> area, the command fails and says "cannot find /, dev mounted?"  But aufs 
> is mounted as "/"
> 
> Of course, not having this fixed, I cannot boot the system.
> 
> Would using knoppix 6.2 to at least boot to a working OS do a better job?
> 
> I am not sure how to fix this problem, when the only working system is a 
> live CD.  Has anyone had this problem and what did you do to fix it?
> 
> Randall

Yes.  I set up a separate hard disk to boot everything from.  I created
an XP NTFS partition of 10 gig first and then a 100 meg I believe Linux
filesystem for grub.  The trick really is figuring out how to refer to
your drives the way grub sees them no matter what the bios does.  All
drives have to be connected and you may find a grub floppy useful.
Personally, I'd like to see grub improve a lot.  I see no reason why
grub shouldn't install as an OS on the second primary partition on the
first hard drive that is capable of detecting grub on other drives,
Windows, Freedos, etcetera.  I used the trick of copying kernels to
the new boot drive to simplify setting grub up.  Error 17 is pretty
darn common and incredibly annoying too ;-)

http://www.linuxquestions.org/questions/linux-general-1/grub-error-17-and-wont-reinstall-using-grub-install-337790/

Check your partition types to make sure something screwy isn't going on.
If your boot partition isn't of type Linux, that's trouble.

Also from a grub boot floppy assuming your boot drive is (hd0,0), do
approximately this...

grub>  setup (hd0,0)
grub>  root (hd0,0)
grub>  kernel (hd0,0)/vmlinuz root=/dev/hdax ro 
grub>  boot

BTW, Slackware 13 and above has grub as an option.  Multiple hard disks
if you run multiple OS'es is an awfully good idea.  Give Windows it's
own disk and give Linux another disk.  Also, consider another hard disk
to install grub to and set that grub up to boot everything.  I think
Slackware 13 and above install disks are the best way to go to fix a
boot loader.