Subject: Re: yaboot disabled from macos
From: Timothy A. Seufert (tas@mindspring.com)
Date: Wed Sep 12 2001 - 14:03:00 MDT
At 3:33 PM -0400 9/12/01, John Klinck wrote:
> I have a curious problem with a dual boot powerbook (G4) running mac os
>9.1 and ydl 2.0. I am using yaboot to choose between the two os. The problem
>is that if I am using macos and even open the control panel for the startup
>disk, yaboot is no longer available but the computer always starts macos.
>
> The temporary fix is to hold the option key on startup which leads to a
>graphics boot loader that allows me to choose which system I want to start.
Once you're in Linux, make sure /etc/yaboot.conf is set up correctly,
then run ybin.
> A linux wizard fixed the problem when it happened earlier, but I did not
>see what he did and he is no longer around to ask. Apparently the order of
>the boot loaders changed and I can not remember where, or how it was
>changed.
FYI -- It's not the order that changed. Open Firmware (the rough
equivalent to a PC's BIOS) has a "boot-device" variable (stored in
nonvolatile memory) which tells it where to look for something to
boot. Only one boot target can exist. The only ordering possible is
that if OF fails to find what "boot-device" tells it to look for, it
will attempt to scan all your partitions for MacOS ROM files.
Which brings me to how MacOS boots. MacOS has no bootloader; OF
directly loads the equivalent of its kernel (the MacOS ROM image) and
starts it. The MacOS startup disk control panel will change the Open
Firmware "boot-device" variable such that it tells OF to scan for a
MacOS ROM file on the MacOS partition.
In order to get your boot menu, you have to have "boot-device"
pointing at the boot menu (ofboot.b) on your Linux bootstrap
partition.
-- Tim Seufert
This archive was generated by hypermail 2a24 : Wed Sep 12 2001 - 13:13:18 MDT