Datasheet

“main” (Installation and Administration) — 2004/6/25 — 13:29 — page 209 — #235
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8
Booting and Boot Managers
If the kernel does not have the needed built-in drivers for accessing the root
partition, initrd must be specified. This is a separate GRUB command
whose only argument is the path to the initrd file. As the loading address
of the initrd is written to the loaded kernel image, the command initrd
must follow immediately after the kernel command.
The root command simplifies specification of kernel and initrd files. The
only argument for the command root is a device or partition (in GRUB
notation). This device is used for all kernel, initrd, or other file paths for
which no device is specified. This applies up to the next root command.
The command is not used in the default menu.lst file created during the
installation. It merely facilitates manual editing.
The boot command is implied and thus automatically executed at the end
of each menu entry, so it does not need to be written into the menu file. If
entering GRUB commands interactively at the prompt, remember to enter
the boot command at the end. The command itself has no arguments. It
merely boots the loaded kernel image or chain loader.
Once you have written all your menu entries, specify which entry to use
as the default. Otherwise, the first one (number 0) is booted by default.
You can also specify a time-out in seconds after which this should occur.
timeout and default usually precede the menu entries. A sample con-
figuration file is described in Section 8.4.1 on the following page.
Naming Conventions for Hard Disks and Partitions
GRUB names hard disks and partitions according to conventions that differ
from the Linux device names, such as /dev/hda1. The first hard disk is
always referred to as /dev/hd0. The floppy drive is called /dev/fd0. The
four primary partitions allowed per disk are numbered from 0 to 3. Logical
partitions are counted beginning with 4.
(hd0,0) first primary partition on first hard disk
(hd0,1) second primary partition
(hd0,2) third primary partition
(hd0,3) fourth primary partition (usually an extended partition)
(hd0,4) first logical partition
(hd0,5) second logical partition ...
GRUB does not distinguish between IDE, SCSI, or RAID devices. All hard
disks detected by the BIOS or other disk controllers are counted according
to the boot sequence set in the BIOS itself.
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SUSE LINUX Enterprise Server