> > > How about "boot scsi/sd@0:0" ?
> >
> > Yes, that works, but boots from the combined MacOS/LinuxPPC
> > disk.  "Not what I was after." ;-)
>
> boot scsi/sd@?:0
>
> where ? is the SCSI ID of the drive you wish to boot from.
>
> On some Macs (e.g. 7500/7600), the SCSI host adapter for the
> internal chain is called 'scsi-int', where the adapter for the
> external chain is called 'scsi'.
>
> boot scsi-int/sd@?:0 etc.

Here's part of what I did today (I see I didn't do exactly as you
suggested -- I'll try that once I get home again):

0 > devalias 
vci0                /chaos@F0000000
pci1                /bandit@F2000000
pci2                /bandit@F4000000
fd                  /bandit/gc/swim3
kbd                 /bandit/gc/via-cuda/adb/keyboard
ttya                /bandit/gc/escc/ch-a
ttyb                /bandit/gc/escc/ch-b
enet                /bandit/gc/mace
scsi                /bandit/gc/53c94
scsi-int            /bandit/gc/mesh
 ok
0 > boot scsi/sd@1:0  can't OPEN: scsi/sd@1:0
 ok
0 > dev scsi ls 
FF834650: /sd@0,0
FF835280: /st@0,0
 ok
0 > boot scsi-int/sd@1,0 -a can't LOAD from this device
 ok
0 > boot scsi-int/sd:1  can't OPEN: scsi-int/sd:1
 ok
0 > boot scsi-int/sd@1 can't LOAD from this device
 ok
0 > boot scsi-int/sd@0  can't OPEN: scsi-int/sd@0
 ok

A complete device listing includes:

FF8317A0: /bandit@F2000000
FF832990:   /gc@10
FF832DC8:     /53c94@10000
FF834650:       /sd@0,0
FF835280:       /st@0,0
...
FF83A930:     /mesh@18000
FF83C498:       /sd@0,0
FF83D0C8:       /st@0,0
...

As you can probably see, I've not really understood what the numbers
after the @ designate, and I'm also fuzzy on my understanding of the
exact syntax (what does the '@' mean, what (if anything) does ':'
mean, why doesn't the second disk show up as a child of "scsi", why
does the first disk show up there (if that's what it does) when it's
not even on that SCSI chain, etc.)  Some of this is probably due to
the current lack of documentation.  If someone can enlighten me on
those points I'll try to write it down in the install notes.

Just as a reminder, when I booted the install floppy, the SCSI
part of the messages were:

esp0 at obio0 offset 0x10000 irq 12: NCR53C94, 25MHz, SCSI ID 7
scsibus0 at esp0: 8 targets, 8 luns per target
...
mesh0 at obio0 offset 0x18000 irq 13: 50MHz, SCSI ID 7
scsibus1 at mesh0: 8 targets, 8 luns per target
sd0 at scsibus1 targ 0 lun 0: <QUANTUM, FIREBALL_TM1280S, 300L> SCSI2 0/direct fixed
sd0: 1222MB, 6810 cyl, 2 head, 183 sec, 512 bytes/sect x 2503872 sectors
sd1 at scsibus1 targ 1 lun 0: <IBM, DNES-309170W, SA30> SCSI3 0/direct fixed
sd1: 8748MB, 11474 cyl, 5 head, 312 sec, 512 bytes/sect x 17916240 sectors
cd0 at scsibus1 targ 3 lun 0: <MATSHITA, CD-ROM CR-8008, 8.0e> SCSI2 5/cdrom removable

Regards,

- Havard