[Duo2400] Re: 8.6 and 10

[Jake Luck]

Ivan, thank you for the detailed explanation. Out of frustration last
night, I installed 9.1 on the same partition where 10 will reside. So far
everything appears to be humming.

BTW, did we ever figure out why is the 10.2 install process so fragile?
My experience has been that only 1 out of every 5-6 reboots to gets one to
the install screen, the remaining time it hangs at "Preparing for
installation".

jake


> From: Ivan Drucker <ivanxqz at yahoo.com>
> Subject: [Duo2400] Re: 8.6 and 10
>
> Nope, but I do switch back and forth between X and 8.6. Here's how:
>
> First, make sure you've got individual partitions for X, 9.1, and 8.6.
>
> First, the basic 9 and X setup:
>
> Install with 9.1 and get everything running.
>
> Set Open Firmware auto-boot? to false, either with XPF (one oef the menu
> items) or manually in Open Firmware (hold down cmd-opt-OF after chime, at
> OF prompt type "setenv auto-boot? false").
> When Open Firmware comes up at startup, I type "bye" to go to OS 9 or
> "boot" to go to OS X.
>
> Once I've got all that working, I can then go to 9 and use the Startup
> Disk control panel *from Mac OS 8.6*, which is the old-school one that we
> all used from the System 6 days. I can then choose 8.6. When I restart,
> and OF comes up, if I type "bye" it will go to 8.6 instead of 9.1. "boot"
> still goes to OS X. If you want to switch back to 9.1, use the same
> control panel.
>
> If you don't want OF coming up every time you turn on the machine, you
> could set auto-boot? to true (manually or via XPF running in 9) and it
> will boot into X by default, but if you want to go to 8.6 you can hold
> down cmd-opt-OF during startup. Don't select the 8.6 System Folder in the
> X Startup Disk control panel because it'll mess up Open Firmware and
> you'll be unable to run XPF to fix it without booting into 9.1 first.
>
> (explanation follows, optional reading)
>
> I think what is going on -- I am not an expert -- is that when you type
> "bye," the Mac just ignores Open Firmware and boots from the same ROM
> instructions that have been in every Mac until the iMac, which look in
> PRAM to see which volume to boot from. The PRAM is set by the Startup
> Disk control panel.
>
> XPF programs Open Firmware to support booting X, and these instructions
> are followed when you type "boot". The 9.1 Startup Disk (and the X
> Startup Disk) control panel also messes with Open Firmware, since it
> itself is designed to support booting X on newer systems, so if you use
> it to switch to 8.6, you'll make X unbootable. However, the 8.6 Startup
> Disk control panel only changes PRAM and leaves Open Firmware alone. Thus
> when you type "bye" and it begins to boot from the ROM, it just starts
> from 8.6. The X startup instructions that are executed when you type
> "bye" still work fine.
>
> If auto-boot? is set to true, the PowerBook automatically executes a
> "boot" instruction. If X is installed, it boots (LinuxPPC uses the same
> technique). For most users who don't have an alternate OS, it does the
> exact same thing as "bye".
>
> Hope this helps,
> Ivan.