How can I boot Debian Linux after have installed Windows? Or: how to restore GRUB?

[Daan]

Hi. I have a Debian installation on my desktop PC, but after installing Windows XP Pro on an other partition, there's no option at boot up anymore to boot the Debian Linux OS: the GRUB menu is gone and my system goes strait into Windows.

How can I restore the GRUB menu? Or just reinstall it?

When I boot up from the Debian installation CD there's an option to install the GRUB boot loader, but when I try to do that, I go to the partitioning section first. My guess is that I have to set a bootable flag or something first before I can install GRUB. Am I right? Would setting the bootable flag on what was my / (root) partition anable me to install a nice GRUB that lets me choose between Debian and Windows?

Thanks,

Daan

[tb10alj]

Hi,

the windoze installation has overwritten your MBR.
An easy way to restore GRUB is to boot from a LiveCD (for example KNOPPIX).

Boot from a LiveCD and mount the partition which contains the boot directory
of your Debian system (i.e. to /mnt/target)

Edit /mnt/target/boot/grub/menu.lst and add an entry for your Windows
installation.

title Windows XP
  # Adjust the root entry for your system!!!!!
  # (hd0,1) is the second partition of the primary master
  root            (hd0,1)
  makeactive
  chainloader     +1
  boot

Type grub to get a GRUB shell. In the GRUB shell, you should first run
the root command, to tell GRUB where to find the necessary files:

root (hd0,0)

(hd0,0) stands for hda1. If your are not sure, which partition you should
enter here, you can figure it out with:

find /boot/grub/stage1

To install GRUB in the MBR of the first drive enter:

setup (hd0)

Now type quit, reboot your system and cross your fingers

Cheers
JAN

[Daan]

Thanks Jan!

I did as you told me and as soon as found out that I had to run the grub command as root, it was really easy. (You can run grub as a normal user, but than it will nor respond as you said it would).

Thanks again,

Daan

[LonelyTraveler]

I did what Jan said, but when I boot I get the following message:

GRUB Loading stage.1.5

(with a bunch of strange signs after it)

Can anyone please tell me what to do. This is really working on my nervs now.

Thank you.

[devils casper]

please provide a little more details. which distro? is there any other OS installed in Harddisk? how many harddisks do you have? is it a fresh install?







Casper

[craigevil]

Here are a couple ways of doing it and hopefully one of them will work for you:

Boot with a Knoppix CD (or some other live-cd), or use a rescue/boot floppy like Tomsrtbt ( http://www.toms.net/rb/ ); determine your root partition and mount it to a temporary mount point; then chroot into it; then reinstall GRUB:

sudo mkdir /mnt/temp

sudo mount /dev/hda1 /mnt/temp
(change /dev/hda1 to match your own root partition)

sudo chroot /mnt/temp

sudo grub-install /dev/hda

or...

determine your root partition, then mount it "dev" option enabled with write permissions. If the filesystem isn't mounted you'll need to mount it like this (be sure to change "hda1" and "hda" to match the location/device in your own system):

sudo mount -o dev,rw /mnt/hda1

if it's already mounted, remount it like this:

sudo mount -o remount,dev,rw /mnt/hda1

now restore grub like this:

sudo chroot /mnt/hda1 grub-install /dev/hda

if it doesn't work using chroot, try remounting as outlined above and do:

sudo grub-install -root-directory=/mnt/hda1 /dev/hda

Kanotix has an option to "Restore Grub", simply boot with the livecd and choose restore grub.

[LonelyTraveler]

please provide a little more details. which distro? is there any other OS installed in Harddisk? how many harddisks do you have? is it a fresh install?

Thanks for the reply. I'm running Debian Sarge and a installation is a few weeks old. I installed Windozs last night witch ate my GRUB!!! I have one hard disk with two partitions. Linux is on the first partition.

[devils casper]

boot up from Debian installation CD and type 'boot=/dev/hda1' at prompt. Debian will boot up. execute 'grub-install /dev/hda' in konsole to reinstall GRUB.






Casper

[LonelyTraveler]

Thank you both so much for your help! Its working now! I did what Craigevil said (the first way) and it worked. I used some other tutorials before posting here, but it didn't want to work. So... Great job Craig!