Dne, 25. 11. 2010 15:41:38 je Hugo Vanwoerkom napisal(a):
Hi,
Since I have a new amd64 mobo, M4N98TD EVO, I am about to do an amd64
install.
Up to now I have run from partitions that were 1386.
And a question: how does switch between an amd64 and an i386 partition
work?
By "switch" you mean booting into i386 as opposed to booting into amd64?
You select that at the Grub's prompt.
Now I am running i386 and grub i386. But when I want to boot the amd64
partition, whose grub is used? Or does the MBR automagically pull the
right grub in?
Hugo
Generally speaking, that would depend on your boot device, as specified
in the BIOS, and on your boot partition, specified in the (I think) MBR.
First, BIOS decides from which block device to boot. It "calls" the MBR
on that block device, which, in turn, has information on which Grub to
call, and where to find it. The discourse gets somewhat more complicated
when LVM or RAID is involved.
Generally speaking again, the Grub that gets called is the *last* Grub
that you installed with install-grub. That would mean that, on a
single-drive system, on which you have 4 partitions with 4 different
distros installed, the last distro you installed will take over and
install its own Grub. On the upside, decent distros will "pick up" your
older distros and make the relative entries in the new Grub menu, so you
will still be able to choose any one of them at boot. On the downside,
the foregoing is an overly simplified, and potentially lacking, overview
of how Grub works.