Need advice for preserving GRUB boot loader.

You can install grub onto sdb, then when windows 7 install destroys the grub on sda, you can change the boot order in your BIOS to boot off sdb first. Boot Ubuntu, then run sudo update-grub to replace the old Windows grub info with the new windows 7 info, and you are done. No need to touch sda again, leaving it a pure Windows disk, with the windows boot loader.

Thank you Ubfan for the reply.

Could you please explain to me how to install grub on sdb?

M

On 11-03-11 08:23 PM, Ubfan wrote:
> Your question #148729 on Ubuntu changed:
> https://answers.launchpad.net/ubuntu/+question/148729
>
> Status: Open => Answered
>
> Ubfan proposed the following answer:
> You can install grub onto sdb, then when windows 7 install destroys the
> grub on sda, you can change the boot order in your BIOS to boot off sdb
> first. Boot Ubuntu, then run sudo update-grub to replace the old
> Windows grub info with the new windows 7 info, and you are done. No
> need to touch sda again, leaving it a pure Windows disk, with the
> windows boot loader.
>

https://help.ubuntu.com/community/Grub2#Reinstalling%20from%20LiveCD
   sudo mount /dev/sdb1 /mnt
   sudo grub-install --root-directory=/mnt /dev/sdb

Thank you Ubfan and Delance for your responses.

I found the instructions I needed here: https://help.ubuntu.com/community/WindowsDualBoot

Things look good. I will close this thread as solved.

Thanks again and the best to you.

Thanks Ubfan, that solved my question.

Dear Delance,

I must have done something wrong. I followed your instructions. when I rebooted after that, I do not get a grub menu but this:

Minimal BASH-like line editing is supported. For
the first word, TAB lists possible command
completions. Anywhere else TAB lists the possible
completions of a device/filename.

This is booting from sda1

I don't know what to do now. I can't get into either xp or ubuntu 10.04. I'm writing this from a live session using my installation disk with which I can access all my files on both hard drives. I know nothing about programing.

Please help me get my grub back.

You could try booting from sdb instead of sda, but if your sdb setup somehow got partially written to sda, the sdb setup probably is not working either. From your live CD, you just need to follow delance's instructions above to install grub onto sdb, and that should boot both windows and ubuntu -- but you have to tell your computer to try sdb before trying sda. Usually you can change a setting in the BIOS setup to do this, or at the first vendor splash screen at boot time, you might have instructions to type a key (ESC for example) to select a boot device.
  If you can successfully boot from sdb, you can backup your XP files, and reinstall Win 7 onto sda, which should fix the bootloader on sda. After installing win7, sda should boot win7 with no sdb attached. When you next run ubuntu, run
sudo update-grub to change the xp boot info to win7 boot info.

The most direct should to install Seven, and then use a Live Session, and follow instruction in https://help.ubuntu.com/community/Grub2#Reinstalling%20from%20LiveCD to reinstall on first disk on boot order . It's usually sda but sometimes it can have another value. If you want to preserve Seven MBR, the solution is to install Seven on first disk, then switch both disks in boot order, and then to reinstall Grub2.

Dear Delance and Ubran,

Thank you for your help. It was kind of you to spend the time and to be so patient. My efforts were not very successful so I went ahead and installed Windows 7 and installed Ubuntu 10.10 afterwards. I had all my files and settings backed up. I lost about a half a day.

The best to you.