Operation Manual
17.1.2 The File device.map
The le device.map maps GRUB and BIOS device names to Linux device names.
In a mixed system containing IDE and SCSI hard disks, GRUB must try to determine
the boot sequence by a special procedure, because GRUB may not have access to the
BIOS information on the boot sequence. GRUB saves the result of this analysis in the
le /boot/grub/device.map. Example device.map les for a system on
which the boot sequence in the BIOS is set to IDE before SCSI could look as follows:
(fd0) /dev/fd0
(hd0) /dev/sda
(hd1) /dev/sdb
or
(fd0) /dev/fd0
(hd0) /dev/disk-by-id/DISK1 ID
(hd1) /dev/disk-by-id/DISK2 ID
Because the order of IDE, SCSI and other hard disks depends on various factors and
Linux is not able to identify the mapping, the sequence in the le device.map can
be set manually. If you encounter problems when booting, check if the sequence in this
le corresponds to the sequence in the BIOS and use the GRUB prompt to modify it
temporarily, if necessary. After the Linux system has booted, the le device.map
can be edited permanently with the YaST boot loader module or an editor of your
choice.
After manually changing device.map, execute the following command to reinstall
GRUB. This command causes the le device.map to be reloaded and the commands
listed in grub.conf to be executed:
grub --batch < /etc/grub.conf
17.1.3 The File /etc/grub.conf
The third important GRUB conguration le after menu.lst and device.map is
/etc/grub.conf. This le contains the commands, parameters and options the
GRUB shell needs for installing the boot loader correctly:
setup --stage2=/boot/grub/stage2 --force-lba (hd0,1) (hd0,1)
quit
The Boot Loader GRUB 251