how to dual boot? (was Re: adding boostrap code to boot system)

[Jeremy C. Reed]

On Sun, 5 Mar 2006, Sascha Wildner wrote:

> > Can someone please tell me how to get DragonFly to boot? And how can I 
> > get a boot selector?
> 
> The boot manager is installed with 'boot0cfg -B'.

Okay. I thought I had tried that, but now I see I used that switch with 
fdisk and disklabel but used different options with boot0cfg. (Without the 
-B I was getting "unknown or incompatible boot code" each time.)

That did give me a boot menu, with:

F1   BSD
F2   ??
F3   DF/FBSD
F4   DF/FBSD

F2 has no operating system. And F1 boots NetBSD and F3 boots FreeBSD fine 
-- thanks!

But F4 just beeps (like when pressing invalid F5).

So I booted with the LiveCD again, created the ad0s4a device node, and 
ran:

  disklabel -B /dev/ad0s4a

Rebooting still didn't fix the F4.

Can someone please summarize the disklabel, fdisk and boot0cfg options 
(maybe with some examples) specifically for making a system bootable and 
also for a multi-boot menu?

And is there a certain order these things are supposed to be done in?

Once I get this figured out, I will make sure this is clearly documented 
in the online DragonFly book.

 Jeremy C. Reed

p.s. I had installed on the laptop using the latest official LiveCD. The 
system already had NetBSD and FreeBSD. I chose not to install the boot 
manager in the DragonFly installer since I didn't want to lose access to 
easily booting to the other systems. I was hoping that the boot menu would 
work immediately.