Boot loaders

Contents

Grub
Reference

Boot loader is the first software program that runs when a computer starts. It is responsible for loading and transferring control to the operating system kernel software.

Grub

Map devices:

grub> map (hd0) (hd1)
grub> map (hd1) (hd0)

A grub entry with device map should looks like:

title Windows 7
    rootnoverify (hd0,0)
    map (hd0) (hd1)
    map (hd1) (hd0)
    makeactive
    chainloader +1

Or you create file device.map with contents:

(hd0)     /dev/sda
(hd1)     /dev/sdb

And then:

# grub --device-map=device.map

Reference

Booting.
GNU Grub.
Multiboot Specification.
Etherboot/gPXE.
SYSLINUX.
Das U-Boot.
NTLDR.
Windows Vista startup process.
Comparison of boot loaders.
boot.kernel.org(BKO) - Booting your machine over HTTP.