> Can someone shed some light on how to format a 640 MB
> SCSI MO disk? I've tried to "newfs" /dev/sd0,
> /dev/sd0a, and beyond, but newfs reports that can't
> find a disklabel. So, I've looked at the disklabel,
> disktab, and newfs man pages, as well as
> "/etc/disktab"...but can't make it happen.
> 
> (I'm used to mke2fs under Linux, so I 'm lost. :-)
> 
> I'm trying to make single-partition, back-up and
> storage disks.

disklabel -r -w /dev/sd0  "MO 300 MB"
newfs /dev/sd0c

Disktab for my Pinnacle + OCU unit: (from the manual, originally for 386BSD)

ocu|OCU| Optical Conversion Unit type 150S (295.4 PMO):\
	:ty=removable:dt=SCSI:ns#64:nt#15:nc#601:\
	:pc#576960:oc#0:bc#8192:fc#1024:tc=4.2BSD