François Patte wrote:

> Bonjour,
>
> I have two HD (sda sdb) and grub installed on the sda MBR.
>
> I want to install grub on the sdb MBR because the system is installed on
> the sdb HD.
>
> At this time, sdb is formatted like this:
>
> / on sdb1
>
> the remaining of this drive is a part of a lvm gathering this remaining
> and a 3rd disk (sdc)
>
> sda has an extended linux partition with / on sda5 and /boot on sda6
> this disk was used in a previous install and is no more in use now,
> except the MBR and the grub.conf file which located in /boot/grub (on
> sda6).
>
> I want to re-format this sda to use it for backups and some other
> things, so I have to move the grub.conf somewhere else (/boot/grub on
> sdb1).
>
> How can I proceed?

I don't really see any problem.
There are 2 bits of grub;
the actual loader which normally goes in the MBR,
and the support files.
You could install grub in the sdb MBR,
provided your BIOS allows you to boot from sdb.
(You will be offered a choice if you go into the BIOS at boot time.)

But there is no reason why you should not have grub in the sda MBR
and /boot with the grub support files on sdb.

Maybe I misunderstood the question.

--
Timothy Murphy
e-mail (<80k only): tim /at/ birdsnest.maths.tcd.ie
tel: +353-86-2336090, +353-1-2842366
s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland