Boot Windows from USB disk with Ubuntu kernel and initrd

Question

I have a situation where I have to boot using Ubuntu kernel and initrd first. Then check for attached USB/SCSI disk which has a Windows Installation and then boot Windows through USB/SCSI disk.

I am curious to know what are the changes I have to make to my bootable ubuntu kernel, in itrd and grub.

score 1 · Answer 1 · answered Jul 02 '10 at 05:52

You should only need a "chainloader" entry in your menu.lst / grub.cfg (depending which version of grub you're using). For legacy grub it's something like

title         Windows 95/98/NT/2000
root          (hd1,0)
makeactive
chainloader   +1

For GRUB2 it depends on the MBR setup, but in general it's something like

menuentry "Microsoft Windows XP" {
    insmod chain
    set root=(hd1,1)
    devicemap -s hd0 hd1
    chainloader +1
}

The exact partition number you'll need to work out based on your setup.

Boot Windows from USB disk with Ubuntu kernel and initrd

1 Answers1