Nice, Ubuntu just wiped out my RAID array...

Having GRUB boot problems, it's booting into Ubuntu but when I select Windows it says NTLDR missing. Is GRUB pointing to the incorrect HD?
 
badbob said:
Having GRUB boot problems, it's booting into Ubuntu but when I select Windows it says NTLDR missing. Is GRUB pointing to the incorrect HD?
Click to expand...

could well be. could be other things, though.

the Windows partition is usually (almost always) the first partition on the disk - which will be hda1 (for pata) or sda1 (for sata).

Check in /boot/grub/menu.lst where the chainloader is pointing.

Also - this seems a bit like a thread hijack... maybe should have made a new thread?
 
# menu.lst - See: grub(8), info grub, update-grub(8)
# grub-install(8), grub-floppy(8),
# grub-md5-crypt, /usr/share/doc/grub
# and /usr/share/doc/grub-doc/.

## default num
# Set the default entry to the entry number NUM. Numbering starts from 0, and
# the entry number 0 is the default if the command is not used.
#
# You can specify 'saved' instead of a number. In this case, the default entry
# is the entry saved with the command 'savedefault'.
# WARNING: If you are using dmraid do not use 'savedefault' or your
# array will desync and will not let you boot your system.
default 0

## timeout sec
# Set a timeout, in SEC seconds, before automatically booting the default entry
# (normally the first entry defined).
timeout 10

## hiddenmenu
# Hides the menu by default (press ESC to see the menu)
#hiddenmenu

# Pretty colours
#color cyan/blue white/blue

## password ['--md5'] passwd
# If used in the first section of a menu file, disable all interactive editing
# control (menu entry editor and command-line) and entries protected by the
# command 'lock'
# e.g. password topsecret
# password --md5 $1$gLhU0/$aW78kHK1QfV3P2b2znUoe/
# password topsecret

#
# examples
#
# title Windows 95/98/NT/2000
# root (hd0,0)
# makeactive
# chainloader +1
#
# title Linux
# root (hd0,1)
# kernel /vmlinuz root=/dev/hda2 ro
#

#
# Put static boot stanzas before and/or after AUTOMAGIC KERNEL LIST

### BEGIN AUTOMAGIC KERNELS LIST
## lines between the AUTOMAGIC KERNELS LIST markers will be modified
## by the debian update-grub script except for the default options below

## DO NOT UNCOMMENT THEM, Just edit them to your needs

## ## Start Default Options ##
## default kernel options
## default kernel options for automagic boot options
## If you want special options for specific kernels use kopt_x_y_z
## where x.y.z is kernel version. Minor versions can be omitted.
## e.g. kopt=root=/dev/hda1 ro
## kopt_2_6_8=root=/dev/hdc1 ro
## kopt_2_6_8_2_686=root=/dev/hdc2 ro
# kopt=root=UUID=9afbd4f6-f850-4364-ac9f-dd919c205ac5 ro

## Setup crashdump menu entries
## e.g. crashdump=1
# crashdump=0

## default grub root device
## e.g. groot=(hd0,0)
# groot=(hd2,1)

## should update-grub create alternative automagic boot options
## e.g. alternative=true
## alternative=false
# alternative=true

## should update-grub lock alternative automagic boot options
## e.g. lockalternative=true
## lockalternative=false
# lockalternative=false

## additional options to use with the default boot option, but not with the
## alternatives
## e.g. defoptions=vga=791 resume=/dev/hda5
# defoptions=quiet splash

## should update-grub lock old automagic boot options
## e.g. lockold=false
## lockold=true
# lockold=false

## Xen hypervisor options to use with the default Xen boot option
# xenhopt=

## Xen Linux kernel options to use with the default Xen boot option
# xenkopt=console=tty0

## altoption boot targets option
## multiple altoptions lines are allowed
## e.g. altoptions=(extra menu suffix) extra boot options
## altoptions=(recovery) single
# altoptions=(recovery mode) single

## controls how many kernels should be put into the menu.lst
## only counts the first occurence of a kernel, not the
## alternative kernel options
## e.g. howmany=all
## howmany=7
# howmany=all

## should update-grub create memtest86 boot option
## e.g. memtest86=true
## memtest86=false
# memtest86=true

## should update-grub adjust the value of the default booted system
## can be true or false
# updatedefaultentry=false

## should update-grub add savedefault to the default options
## can be true or false
# savedefault=false

## ## End Default Options ##

title Ubuntu 7.10, kernel 2.6.22-14-generic
root (hd2,1)
kernel /boot/vmlinuz-2.6.22-14-generic root=UUID=9afbd4f6-f850-4364-ac9f-dd919c205ac5 ro quiet splash
initrd /boot/initrd.img-2.6.22-14-generic
quiet

title Ubuntu 7.10, kernel 2.6.22-14-generic (recovery mode)
root (hd2,1)
kernel /boot/vmlinuz-2.6.22-14-generic root=UUID=9afbd4f6-f850-4364-ac9f-dd919c205ac5 ro single
initrd /boot/initrd.img-2.6.22-14-generic

title Ubuntu 7.10, memtest86+
root (hd2,1)
kernel /boot/memtest86+.bin
quiet

### END DEBIAN AUTOMAGIC KERNELS LIST

# This is a divider, added to separate the menu items below from the Debian
# ones.
title Other operating systems:
root


# This entry automatically added by the Debian installer for a non-linux OS
# on /dev/sdc1
title Microsoft Windows XP Professional
root (hd3,0)
savedefault
makeactive
map (hd0) (hd3)
map (hd3) (hd0)
chainloader +1

80GB is HD1- should have bootloader in that (HD0)
SDC1 is the HD where Windows is installed
 
I'm not too up on the chainloader side of grub, as I don't use it - so I'm not sure what the
Code: 
map (hd0) (hd3)
map (hd3) (hd0)
section is all about... probably google that bit - but change
Code: 
root (hd3,0)
to
Code: 
root (hd0,0)

EDIT: Although - if Windows is installed on sdc1 - that is the first partition on the third sata disk...

Where is GRUB installed?
 
GRUB cannot boot DOS or Windows directly, so you must chain-load them (see section Load another boot loader to boot unsupported operating systems). However, their boot loaders have some critical deficiencies, so it may not work to just chain-load them. To overcome the problems, GRUB provides you with two helper functions.

If you have installed DOS (or Windows) on a non-first hard disk, you have to use the disk swapping technique, because that OS cannot boot from any disks but the first one. The workaround used in GRUB is the command @command{map} (see section map), like this:

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

This performs a virtual swap between your first and second hard drive.

Caution: This is effective only if DOS (or Windows) uses BIOS to access the swapped disks. If that OS uses a special driver for the disks, this probably won't work.

Another problem arises if you installed more than one set of DOS/Windows onto one disk, because they could be confused if there are more than one primary partitions for DOS/Windows. Certainly you should avoid doing this, but there is a solution if you do want to do so. Use the partition hiding/unhiding technique.

If GRUB hides a DOS (or Windows) partition (see section hide), DOS (or Windows) will ignore the partition. If GRUB unhides a DOS (or Windows) partition (see section unhide), DOS (or Windows) will detect the partition. Thus, if you have installed DOS (or Windows) on the first and the second partition of the first hard disk, and you want to boot the copy on the first partition, do the following:

grub> unhide (hd0,0)
grub> hide (hd0,1)
grub> rootnoverify (hd0,0)
grub> chainloader +1
grub> makeactive
grub> boot
Click to expand...

answers the "map" question
 
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