Ubuntu/Ubuntu dual boot and grub2

[Tom H]

On Sun, Oct 31, 2010 at 1:18 PM, Colin Law <clanlaw at googlemail.com> wrote:
>
> I have a system with Lucid installed, and have installed Maverick on a
> small separate partition in order to check it out prior to upgrading
> my Lucid partition.  This works fine except that the Maverick
> partition is what one might call the master partition in the sense
> that it appears at the top of the grub boot list, and if I want to
> change boot options I do it in /default/grub in the Maverick
> partition.
>
> I would like the Lucid partition to be the master one so that at some
> point I can simply remove the Maverick partition and upgrade Lucid.  I
> guess I can do this using the same method as for when Windows messes
> up the MBR, as described in [1].  Is there a better or easier way?
>
> [1] https://help.ubuntu.com/community/RecoveringUbuntuAfterInstallingWindows

I haven't checked the link but the way to make Lucid's "/boot" the
master grub directory is to boot into Lucid and run "sudo grub-install
/dev/sdX" where sdX is the boot device.