grub mysteries

Jason Stephenson jason at sigio.com
Sun Jan 9 02:07:00 EST 2005


Jeff Macdonald wrote:

> However, that's under Linux. When booting however, Grub sees something
> else. hd3 becomes hd1! hd1 becomes hd2! Changing grub.conf to point to
> the correct devices doesn't help. I'm only able to boot using a floppy
> and specifying root, kernel and initrd command by hand. Has anyone
> else seen this? This is not a PCI bus ordering thing where ide=reverse
> would fix things.

Grub can be told to map drives to different locations, essentially 
fooling the OS into seeing the drives as having a different "letter" in 
the BIOS. It could be that you have some of that going on in a menu.lst 
or grub.conf file. I'll wager that it may have been added automagically 
by the install software of either Fedora or Gentoo.

When I configured a workstation to dual boot with MS Windows 2000 on a 
second hard disk, I had to use grub's map command to fool Windows into 
believing it was on the first BIOS drive, or Windows would not boot.

Look in the grub config files, usually under /boot/grub subdirectory, 
for lines like the following:

map (hd1) (hd0)

Where hd1 and hd0 could be other grub drive specifications.

Another possibility could be the Adaptec controllers playing with the 
BIOS' view of the drives and their ordering. I've not ever used an 
Adaptec IDE controller, but I did have to reconfigure an AHA-2940 
controller in order to get it to work properly with grub on the system 
described above.

Cheers,
Jason




More information about the gnhlug-discuss mailing list