Linux Desktop Hacks

Give Your Computer the Boot #1

Chapter 1, Booting Linux

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HACK

It’s important to note how GRUB deals with disks and partition numbers.

Unlike Linux, GRUB refers to the first disk as

hd0 and the first partition as par-

tition

0. In Linux this is designated as /dev/hda1. Basically, if the letters that des-

ignate the hard drive in Linux were numbers, you would subtract 1 from them.

Therefore, an a (1) becomes 0, a b (2) becomes 1, and so on. Also, you would

subtract 1 from the partition number itself. For example, a boot partition

located on /dev/hdb3 becomes

hd1,2 in GRUB parlance. In the previous stanza,

you refer to the location of the kernel (

root)ashd0,0, but on the kernel line,

you refer to the root partition as /dev/hda3. Because it is a kernel parameter, it

uses the normal Linux method of referring to disks and partitions. The final

part of the stanza uses

savedefault to make the stanza a default option in the

GRUB menu, and the command

boot actually boots the system.

If you want to add another operating system, simply add it elsewhere in the

configuration file. A Windows stanza looks like this:

title Windows 95/98/NT/2000

root (hd0,0)

makeactive

chainloader +1

When you are booting non-Linux operating systems (most likely Win-

dows), you usually will need to use the

makeactive and chainloader key-

words. The

makeactive keyword is used to set this partition as GRUB’s main

root filesystem device. The