In article <20031124174214.GC2262@antioche.lip6.fr>
bouyer@antioche.lip6.fr wrote:

> (I couldn't get a NetBSD CD to load,
> although it can boot a macos CD,

How dows it fail? On my Apus2000, Openfirmware fails to boot from
SCSI CD-ROM just after powerup, but it works once after CTRL+CMD+POWER:
---
[...power on...]
Open Firmware, 2.0
To continue booting the MacOS type:
BYE<return>
To continue booting from the default boot device type:
BOOT<return>
 ok
0 > boot scsi/sd@3:0 DEFAULT CATCH!, code=FFF00300 at   %SRR0: FF80AC9C   %SRR1: 0000B070 
[...hangup, then CTRL+CMD+POWER here...]
Open Firmware, 2.0
To continue booting the MacOS type:
BYE<return>
To continue booting from the default boot device type:
BOOT<return>
 ok
0 > boot scsi/sd@3:0 
>> NetBSD/macppc OpenFirmware Boot, Revision 1.6
>> (autobuild@tgm.daemon.org, Sun Sep  8 21:53:46 UTC 2002)
open /netbsd: Device not configured
open /netbsd.gz: Device not configured
5946708+219188=0x5e179c
 start=0x800000
[ netbsd ELF symbol table not valid ]
[ no symbol table formats found ]
Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002
    The NetBSD Foundation, Inc.  All rights reserved.
Copyright (c) 1982, 1986, 1989, 1991, 1993
    The Regents of the University of California.  All rights reserved.

NetBSD 1.6 (GENERIC_MD) #0: Sun Sep  8 22:12:49 UTC 2002
    autobuild@tgm.daemon.org:/autobuild/macppc/OBJ/autobuild/src/sys/arch/macppc/compile/GENERIC_MD
 :
---

> It accepted wd0c as root, and I could restore the disklabel from /var/backup.
> rebooted, and got "can't LOAD from this device" again.
> So it seems to be an issue with the disklabel.
> Any idea of what's going wrong ?

I don't know how -current macppc/disksubr.c was designed/implemented,
but if your disk has MBR, installboot(8) breaks disklabel on the disk,
and disklabel(8) would break the "faked" apple partition map written by
installboot(8), which was designed for OF 1 and 2 machines.
Maybe you could try zero'ing out first 8k on the disk and then disklabel
and installboot.
---
Izumi Tsutsui
tsutsui@ceres.dti.ne.jp