booting from wrong disk

PJ af.gourmet at
Thu Oct 15 18:42:23 UTC 2009

Polytropon wrote:
> On Thu, 15 Oct 2009 12:13:08 -0400, PJ <af.gourmet at> wrote:
>> add another thought...
>> If I change the mbr on the ad12 then mount ad4s1a to /mnt copy
>> /mnt/boot/boot0 to /boot/boot0.tmp and then copy the modified
>> /boot/boot0 (for ad4) back to /mnt/boot/ and then umount ad4s1a --- I
>> should be ok, OK? Have I got it?
> Why not just remove the "active" marking from the disk you do
> not want to be booted from? Furthermore, I'm not sure if the
> desired operation can be performed UFS-file-wise...
> The easiest way really is to use sysinstall. It's the lazy man's
> swiss army knife. :-)
Yeh, but even with a swill army knife you can cut yourself.  ;-)
But sysinstall will overwrite all the info on the disk and that defeats
the whole purpose of the exercise.
What complicates matters is the use of GAG as boot manager. If I select
to boot from ad4 and the boot is from ad12, then there is something
wrong. It indicates to me that the mbr is loading the wrong disk.
I noticed this when trying to boot a disk on my other computer... it was
looking for ad12 when there was no ad12 installed. I found that strange,
but then I recalled thatManolis Klagias had warned about something of
the sort. Now, I'll have to sort that out.
And you think you're lazy... this is back-braking work for me... :-D

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