Subject: scsi drivers, zip disk, ufs and ffs, and questions therein
To: port-mac68k <port-mac68k@NetBSD.ORG>
From: Jeffrey Ohlmann <jaohlma@BGNet.bgsu.edu>
List: port-mac68k
Date: 11/08/1997 19:34:07
Okay, I'm trying very hard to understand what's going on between my 
internal HDD and zip drive.

Both drives are 'root&usr' partitions with bootable kernels on them.  
(Needless to say, I can only boot from one at a time.  But both contain 
functioning NetBSD/mac68k systems).  The HDD is now my primary BSD 
system; the zip is a holdover, but I keep it around as a sort of backup.

The specifics of the problem are that the HDD, as far as I can determine,
really needs the ncrscsi driver to work (current kernel is Generic-45. 
GenericSBC-45 fails on repeated trials).  On the other hand, the general
consensus is that zip disks need the sbc driver.  My experiences agree
with this opinion.

When booted from the HDD into single-user mode, I can mount the zip and
access it, seemingly without difficulty, in either read-only or
read/write.

However, when the zip is mounted read-write, the machine complains that
/dev/sd1a (the zip) is not clean.  When I check it with fsck_ffs (and/or
with plain fsck, I _think_), the machine crashes.

Immediately after this (after restarting the Mac, that is), I boot from
the zip, also into single-user.  Once there, both fsck and fsck_ffs insist
that the disk (the zip) is clean.  (I do not attempt to mount the HDD 
from the zip for fear of damaging that disk.)

Possibly related to all this, or perhaps not, is that an examination of
/etc/fstab on each disk reveals that the HDD is "ffs" and the zip is
"ufs".

My questions, then, are as follows:

	-What is the difference between ufs and ffs?
	-Would a newly formatted zip, as a 'usr' only partition, be a 
	 better test subject?
	-Given the apparent driver incompatibility of these disks, is
 	 there any hope of using them together?

Any help or information is appreciated.

The machine is a P550, with FPU, 12MB R.AM.
The HDD is a DEC DSP3107 1021 MB.  BSD paritions (root&usr and swap 
combined) get about 160MB of this.


Thanks in advance,


Jeffrey Ohlmann