multiboot grub2 issue

[Foz]

Hi
I had WinXP and Mint 11 on sda1 and sdb1 and everything was good.
When I installed Mint 12 on sdb5 it set up grub2 for itself (using the scripts on sdb5). All three OS are available at boot and work fine.
The problem is I want to keep using the configuration on sdb1, how do I get the mbr to point to this partition?
I have read the manual and trawled the net and the only solution seems to be re-installing grub2, but this seems excessive, is there a better way?

foz

[olle]

I have not LM11 installed right now, but isn't there "Startup Manager" in System maintanance or in the control center ? There you can define which one is the starting installation.

[Foz]

This only allows me to change the default menu choice. It still uses the configuration on mint 12 (sdb5), which I have installed to play with Gnome3 and I may well break.
It does not allow me to set sdb1 as root for boot.

[olle]

In terminal:

Code: Select all

gksu startupmanager

[Foz]

same program same effect. The only difference is it outputs the results of grub-update to the terminal.
It does not affect the mbr and gives no option to change it.

[olle]

Running "gksu startupmanager" should produce this:

Startupmanager.png

Then select the default boot, in my case it is LM9,

Perhaps you have to run this in LM11 ?

[Foz]

This is a subtle distinction, which may be being lost in translation.

Changing this setting makes Mint 11(sdb1) the default choice on the grub config menu on mint 12 (sdb5). It DOES NOT set Mint 11(sdb1) as the boot partition.

Lets say I decide to remove Mint 12 and use the space to store haiku (i.e. format sdb5 where the grub currently in use lives).
The computer will not boot. Even though there is a perfectly good grub setup on sdb1.
How do I convince grub to use this configuration.

[olle]

http://ubuntuforums.org/showthread.php?t=1195275

13. Reinstalling GRUB 2 from LiveCD

HTH