Re: Dual boot GNU and Windows 7

[Piscium]

On 26 March 2011 14:00, Sebastian Tennant <address@hidden> wrote:
> Hi list,
>
> I have a new Lenovo IdeaPad laptop and I would like to keep the Windows
> installation for testing websites in Internet Explorer.
>
> At the moment the hard disk looks like this:
>
>  /dev/sda1 - ntfs     - no label    - Windows boot partition (200 MiB)
>  /dev/sda2 - ntfs     - no label    - Main Windows partition (422 GiB)
>  /dev/sda3 - extended -
>  /dev/sda4 - ntfs     - LENOVO_PART - ??? (15 GiB)
>  /dev/sda5 - ntfs     - LENOVO      - ??? (29 GiB)
>
> The two LENOVO* partitions are for Lenovo's OneKey Rescue(TM) system which I
> will *never* use so my plan is to get rid of them completely,
> shrink /dev/sda2 down to about 48 GiB (using a gparted live disk),

What version of Windows do you have? I remember reading a while back
that resizing Windows Vista partitions with Gparted can make it
unbootable (XP should be fine though). Not sure if that is still the
case, or what is the deal for Windows 7.

> add a large FAT data storage
> partition (which can be used by both GNU and Windows) and finally create a few
> (small) partitions for different flavours of the GNU operating system:
>
>  /dev/sda1 - ntfs     - no label    - Windows boot partition (200 MiB)
>  /dev/sda2 - ntfs     - no label    - Main Windows partition (48 GiB)
>  /dev/sda3 - FAT      - FAT storage - Data storage partition (384 Gib)
>  /dev/sda4 - extended -
>  /dev/sda5 - ext3     - Debian      - GNU OS (10 GiB)
>  /dev/sda6 - ext3     - Gentoo      - GNU OS (10 GiB)
>  /dev/sda7 - ext3     - Fedora      - GNU OS (10 GiB)
>  /dev/sda8 - swap     - no label    - 4GB RAM (4 GiB)

Usually it is recommended to put swap towards the beginning of the
disk as disk access is faster. 4 GB may be excessive, I have 3 GB swap
in mine and I don't remember ever using more than 100 MB.

>
> I've installed GNU OSes several times in the past but I've never needed to
> worry about an existing Windows installation before so I suppose I have two
> questions:
>
>  1. When I install the first of these GNU operating systems (Debian Squeeze),
>    should I opt to overwrite the existing Windows bootloader in the Master
>    Boot Record (MBR) with grub2?

Grub does not "overwrite the existing Windows bootloader" rather it
overwrites the MBR which in your case points to the Windows boot
loader.

Anyway, the combination of Grub2 + os-prober works reliably so I
wouldn't expect and issue.

>  2. If Windows won't boot from grub2 (for whatever reason) after I've written 
> a
>    suitable grub stanza for it, is there a way of restoring the original
>    Windows bootloader to the MBR so that I can continue to use Windows while I
>    think about an alternative approach?

Yes, there is a way. In fact that happened to me once. You need the
Windows CD that came with your PC, set your BIOS to boot from CD.
After you boot from the Windows CD you go in Windows command mode
(that is no graphical interface), I think you need to choose a rescue
option. There is a command to restore the MBR so that it makes it
point again to the Windows boot loader. I forgot what it is but should
be easy for you to google it. After you run the command you reboot
normally (without the CD) and it goes into Windows.