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Dual booting Redhat 7.2 and Windows XP Version 1.1
(638 total words in this text)

Contributed by John Oates - jpoates@eos.ncsu.edu
Updated Apr 29, 2002

This HOW-TO specifically details how to create a dual boot system using
Redhat Linux 7.2 and Windows XP with a NTFS file system using the GRUB
boot loader.

The Problem: The problem was stumbled upon after I successfully
persuaded my Windows XP-using-friend to install Redhat Linux 7.2 onto
the empty end of his hard drive. "Sure." I tell him, "dual booting will
be no problem!" A few days later he calls me up frustrated saying that
he can no longer access his Windows XP operating system....

The procedure I gave to my friend for the install was one that I had
learned from past experience. Knowing how MS Windows XP likes to
overwrite the MBR(Master Boot Record), I tell him to:

   1. fdisk the Hard drive and make a partition for Windows XP and leave
whatever you want to allocate to Linux unpartitioned.
   2. Install Windows XP onto this partition. (This should be a primary
partition!)
   3. Boot to the Linux install CD and partition the remaining
unpartitioned part of the HD and install linux. (Install GRUB into the
MBR, it should detect both OSes)
   4. Reboot and enjoy your new dual boot system! 

Redhat 7.2 uses the new GRUB bootloader. During the Redhat install, Grub
actually *WILL* detect your NTFS XP partition. However, if you do not
give this partition a label at that time, then booting to your Windows
XP OS will not be an option under GRUB. It is apparent that many (and I
mean thousands!) have overlooked this step during the install process,
and hence the need for this article. If booting to Windows XP is not an
option for you at boot, then you have missed this step and the lines
below will solve your problem by manually editing a configuration file
and labeling the partition so that it is selectable at boot.

My friend missed this step as well and panicked when he couldn't get to
Windows. His first instinct of course was to reinstall Windows. A
typical microsoft approach, but "No" I tell him, "The XP operating
system is still on your harddrive, GRUB simply cannot see it." Having
very little experience with GRUB, since previous releases use LILO, I
was unsure how to fix the problem. I had a good guess it was probably
just a simple mod to the /etc/grub.conf similar to how LILO operated.
Indeed this is the answer! I scoured the net for quite a long time
looking for the few lines of code that would enlighten GRUB to the
existence of XP. I found that many others had dealt with the exact same
problem. Unfortunately, a proper answer was more than I could hope for!
So here is the solution for all to see who might try this very common
procedure. Add the following lines to the /etc/grub.conf file:

title Windows XP

        root (hd0,0)

        makeactive

        chainloader +1

As it says in the grub.conf file. You do not have to restart GRUB as you
did LILO for the changes to take affect. Simply save the file and
reboot. All should be well. If you find yourself in a similar
circumstance but you are using LILO instead, these lines can be added to
the /etc/lilo.conf to fix the problem:

other=/dev/hda1 (device XP is installed on)

label=Windows XP 

table=/dev/hda 

Restart LILO (I believe you can just type lilo at the prompt to do this)
and then reboot. I hope this short HOW-TO of my experience with dual
booting XP and Linux on the same HD has helped you. My apologies if your
system has further issues that this document does not solve. I am no
Linux expert, just a hobbyist trying to document my findings.