_

title           Debian GNU/Linux, kernel 2.6.7
root            (hd0,1)
kernel          /boot/vmlinuz-2.6.7 root=/dev/hda2 ro
savedefault
boot
 
title           Windows NT/2000/XP
root            (hd0,0)
savedefault
makeactive
chainloader     +1
 
title           Windows 2
rootnoverify    (hd0,0)
makeactive
chainloader     +1

quentin# sfdisk -l /dev/hda
 
Disk /dev/hda: 116374 cylinders, 16 heads, 63 sectors/track
Units = cylinders of 516096 bytes, blocks of 1024 bytes, counting from 0
 
   Device Boot Start     End   #cyls    #blocks   Id  System
/dev/hda1   *      0+ 104183- 104184-  52508421    7  HPFS/NTFS
/dev/hda2     104184  115798   11615    5853960   83  Linux
/dev/hda3     115799  116373     575     289800    f  W95 Ext'd (LBA)
/dev/hda4          0       -       0          0    0  Empty
/dev/hda5     115799+ 116373     575-    289768+  82  Linux swap

puis apres il faut que tu remete grub en bootant avec debian en mode rescu

error loading operating system

> root (hd0,1)
> setup (hd0)

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Prevention and Recovery of XP Dual Boot Problems
 
    * From: Jack Aboutboul <jaboutboul speakeasy net>
    * To: fedora-devel-list redhat com
    * Subject: Prevention and Recovery of XP Dual Boot Problems
    * Date: Tue, 25 May 2004 17:25:06 -0400
 
This is the whole document for those who didnt get it.
 
<---BEGIN--->
 
Dual Booting Issues With Fedora Core 2 and Windows: Prevention & Recovery
 
NOTICE: Please read this document in its entirety.
 
This guide was inspired by the solution developed by Radu Cornea and  
Alexandre Oliva in this thread:  
http://www.redhat.com/archives/fed [...] 02114.html .  
This guide aims to integrate the original solution with the refinements  
evolved in that thread.  This guide offers an explanation of why the  
refinements are beneficial and some workarounds to problems that may prevent  
the uninitiated from using the solution. It also provides a means of  
preventing the problem entirely.
 
Primer:
 
        There is a bug in Fedora Core 2 that causes the hard disk geometry as  
reported in the partition table to be altered during installation.  This  
change may cause Windows boot failure.  Although this bug is severe, it is  
recoverable and no data should be lost.  It is important not to panic if and  
when this happens so you do not cause further problems or cause actual loss  
of data in the process of recovering from the error.
 
Prevention:
 
        This bug can be avoided entirely by using some preventative steps while  
installing Fedora Core 2.  Thanks go out to Cero (cero coolnetworx net) for  
discovery and testing of this solution.
 
        To avoid the hard disk geometry to be altered you may enter it manually  
during installation by using the hdN=<drive geometry> parameter (where N is  
the letter representing the drive with the MBR you will use).  To discover  
the current geometry before installing Fedora Core 2 you should use a  
utility that can read the drive geometry as reported in the partition table.  
It is important to understand that some tools may not be reporting the  
actual data from this location, but, rather, some derived value, so your  
surest way is to use the fdisk utility.  You can get this information by  
following these steps.
 
Note: This example will assume you are looking at /dev/hda, which is the  
master on the primary IDE interface. If your MBR is located on another  
device you should use its name (eg: /dev/hde )
 
Download and burn the Fedora Core 2 Rescue CD.
 
Boot from the Rescue CD (there is no need to start networking or mount  
drives)
 
Issue the command: fdisk -l /dev/hda   to print the current partition table  
to screen in non-interactive mode.
 
Write down the drive geometry as reported at the beginning of the output  
from fdisk. This is reported as number of Cylinders, Heads, and Sectors  
(hence the name CHS).
 
You can now reboot the computer by simultaneously holding down the keys  
Ctrl-Alt-Delete.
 
You can now boot the Fedora Core 2 installation CD. At the first menu prompt  
you should now choose to run the installer with the known geometry.
 
Example: linux hda=14593,255,63
 
        The installer should now run normally and not alter your partition table  
geometry entry.  If, for any reason, this geometry should be changed  
regardless of this preventative step, please use the recovery steps to  
correct the geometry of the drive as reported by the partition table.
 
 
Recovery:
 
        You have installed Fedora Core 2 and find that you cannot boot Windows.  
Typically the boot process will terminate with the words
 
        Rootnoverify(hd0,0)
        Chainloader +1
 
        These are the boot parameters from your Grub configuration.  The parameters  
are likely to be correct, but Windows fails to boot because Fedora Core 2  
altered the hard disk geometry as reported by the drives partition table.
 
IMPORTANT: Do not panic and do not begin using multiple tools in an attempt  
to correct this error. Automated tools can be very dangerous. The actual  
changes that need to be made are minor and benign.  By running 3rd party  
applications to recover a bootable Windows installation may cause you to  
lose your data.  You have been warned.
 
        For those who are technically inclined I include here a brief explanation  
of what is going on.  The drive has not been damaged and your partition  
table is fine.  The problem is that Windows demands a "sane" CHS table.  
This table has been altered by Fedora Cores installer and Windows hangs.  
Luckily, the actual table, in LBA format, is not  corrupted.  For those  
seeing a strange partition table, take note that you are probably looking at  
the table in CHS values and these values are derived from the geometry.  The  
GNU/Linux operating system does not use these values and operates purely  
with LBA values.  Windows should not be using CHS either, but for some  
reason it at least checks this geometry and can be prevented from booting by  
them being bad.  Changing the drive geometry changes the CHS partition table  
because this is a virtualization of the true state of affairs on the drive  
which are best described as being mystical.  Think of CHS geometry as a  
compass.  If you change the geometry you have recalibrated where the  
needles reference point is and you are no longer looking at true north.
 
        The solution to this problem is very simple, but it may confuse people  
because most people will question why they are seeing strange values  
reported from their partition table in CHS format.  If you do not trust this  
solution or your ability to follow these steps then you should stop and seek  
hard disk recovery consulting services.  The Fedora Project is in no way  
liable for any data loss and this guide is offered without guarantees.  You  
are taking responsibility for what happens.  Now, let us go through the  
solution.
 
        Because only the drive geometry is altered there is no need for manual  
intervention in the form of discovering and entry of partition information.  
The information in your partition table is correct.  However, you need to  
alter the geometry entry and normally this would require you to re-enter the  
partition table by hand using a tool like fdisk.  This is where the  
application sfdisk comes to the rescue. Sfdisk can be very powerful in  
non-interactive mode, it can output information that can be used as input  
elsewhere, and it can accept data as input at run-time.  This makes sfdisk  
ideal for this solution because you can ask it to read the partition table  
and deliver the result in a way that itself can write back when you tell it  
to change your drive geometry.  This makes the process fast and less prone  
to human error as very few values need to be supplied.  The solution can be  
summed up in a single line with two commands:
 
        sfdisk -d /dev/hda | sfdisk --no-reread -H255 /dev/hda
 
        So that the reader may better understand what is going on here, lets go  
through what each section does and what the parameters mean.
 
sfdisk -d /dev/hda
 
This part runs sfdisk non-interactively and dumps the partition table in a  
format that sfdisk can also use for input (as we are doing).  Try this  
command by itself to see your partition table as it is very safe.  You will  
want to check to check for warnings in the output.  Warnings pose a problem  
because they interfere with the use of this data as input. Output containing  
a warning may look like the example below:
 
$ sfdisk -d /dev/hda
Warning: extended partition does not start at a cylinder boundary.
DOS and Linux will interpret the contents differently.
# partition table of /dev/hda
unit: sectors
 
/dev/hda1 : start=       63, size= 16771797, Id= 7, bootable
/dev/hda2 : start= 16771860, size=217632555, Id= f
/dev/hda3 : start=        0, size=        0, Id= 0
/dev/hda4 : start=        0, size=        0, Id= 0
/dev/hda5 : start= 16771923, size=104856192, Id= 7
/dev/hda6 : start=121628178, size=112776237, Id= 7
 
 
For reasons unknown, using the option -- quiet does not suppress all  
warnings so it becomes the task of the user to discover a way to still use  
the output as input.  The simplest way is to write the output to a plain  
text file, editing out the warning in that text file, and using the edited  
text file as the input, thus:
 
sfdisk -d /dev/hda > MyPartitionTable.txt
        editing MyPartitionTable.txt to remove the warnings, saving the edited  
text, and
cat MyPartitionTable.txt | sfdisk --no-reread -H255 /dev/hda
 
The output from "sfdisk -d /dev/hda" should begin like this (this is the  
edited version of the example given before):
 
# partition table of /dev/hda
unit: sectors
 
/dev/hda1 : start=       63, size= 16771797, Id= 7, bootable
/dev/hda2 : start= 16771860, size=217632555, Id= f
/dev/hda3 : start=        0, size=        0, Id= 0
/dev/hda4 : start=        0, size=        0, Id= 0
/dev/hda5 : start= 16771923, size=104856192, Id= 7
/dev/hda6 : start=121628178, size=112776237, Id= 7
 
        Note that "cat MyPartitionTable.txt" takes the place of "sfdisk -d  
/dev/hda" as these are now equivalent. In this case the warning portion has  
been stripped, preserving the needed data used by sfdisk in step two of the  
command.
 
sfdisk --no-reread -H255 /dev/hda
 
        This portion of the two-part command performs the actual change to your  
hard disk.  This main operation is in -H255. This tells sfdisk to write a  
head count of 255 into the drive geometry.  This command executed by itself  
would ask for user input of the partition table (just like fdisk).  However,  
by piping the table we just read in the first command, this is avoided and  
work is saved and we know the data is correct (or, at least, unchanged).  
This is why sfdisk is used.
 
        The --no-reread option allows the command to run even when the disk has a  
mounted partition.  Some users may find they need to further force the  
operation to complete. This is done by using --force (sfdisk --no-reread  
--force -H255 /dev/hda).
 
        In this example we are only changing the number of heads in the geometry.  
If you know the correct number of cylinders before the Fedora Core  
installation changed these values you may also write back this number.   An  
example with 14,593 cylinders is provided below.
 
sfdisk -d /dev/hda | sfdisk --no-reread -H255 -C14593 /dev/hda
 
        The number of reported sectors (S) should not have changed and remained as  
63.
 
        This is the part most likely to be met with the question "if I change the  
number of heads, must I not also change the the number of cylinders?"  The  
answer to this question is "no."  When the geometry was changed the number  
of heads changed from 255 to 16 and the number of cylinders was increased to  
compensate.  As long as the values are large everything should be ok.  Only  
the pedantic need worry about changing the number of cylinders manually.  If  
you do not know the value from before you are best off not supplying this  
number.
 
        By using this method there is no need, and indeed you should not, run a  
program that wipes the MBR (like fdisk /mbr).  Doing so will cause you to  
lose the Grub pointer installed in the MBR and you will have to use the  
Recovery CD to regain access to your Fedora Core installation.
 
        Updating Grub after installation seems to have no effect on the drive  
geometry as the problem seems strictly limited to the Fedora Core installer.
 
Good luck and join us on the IRC at #fedora on irc.freenode.net for any  
questions you have or contributions to the community you wish to make.
 
 
 
    * Follow-Ups:
          o Re: Prevention and Recovery of XP Dual Boot Problems
                + From: Chris Chabot
 
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