Installing grub for a different computer

[Kevin Freeman]

On Tue, 2004-11-16 at 07:55 +0000, Colin Paul Adams wrote:
> root (hd0,4)
> configfile /etc/grub.conf
> 
> (Disk has FC1 on it, if that is relevanet).
> 
> This then attempts to boot a kernel (I'm not presented with a grub
> menu - I guess there's only one kernel present).
> 
> But fails with a message something like:
> 
> Disk (hd1,4) not found.
> 

OK, so this time Murphy's Law is working overtime.  Boot with the floppy
and this time enter:
root (hd0,4)
cat /etc/grub.conf  #if this does not work, cat /boot/grub/menu.lst
or /grub/menu.lst

Now you need to duplicate the kernel and initrd lines that were printed
by the cat command:
kernel /vmlinuz-some-version and some params
initrd /initrd-some-version.img

Note:  use tab completion to save some typing and prevent mistakes.

After entering the commands above for root, kernel and initrd grub is
now ready to resurrect your FC installation.  Enter the command boot and
press enter.

Once the system boots, edit grub.conf (the HD version) and replace hd1
with hd0.  Also, enter a nonzero value for timeout (5 or 10 seconds is
fine) so that if you have to use a boot floppy in the future, the menu
can be displayed (and then modified) with the configfile option.  It
would be a good idea to test the grub floppy again with the commands:
root (hd0,4)
configfile /etc/grub.conf

If this brings up the working grub menu then you know your "emergency
recovery" procedures will work in the future.

> There used to be ANOTHER hard disk in this machine, before that one
> proved to be unusable, so I'm guessing that this hard disk must have
> been the primary IDE slave (is that what hd1 is?).

That is the source of your problem.  If you swap, move or replace drives
you need to be careful with grub.conf to ensure that you still have a
bootable system.  Now that you are armed with a grub floppy (and know
how to use it) this is less of a concern.

Kevin Freeman