On Sun, 12 Apr 1998, Bill Studenmund wrote:

> On Sun, 12 Apr 1998, Frederick Bruckman wrote:
> 
> > That's a consequence of using -x1 with newfs. Without it, all the blocks
> > get used, but the system crashes. I did it both ways a couple of times to
> > be sure it was real. All I can think of now, is that there's a problem
> > with a single block somewhere on the drive. Perhaps, by scrambling things
> > up, that block is being avoided, for now anyway. I'm not so sure about
> > that either. On another drive, the Nomai 540M that I used to boot NetBSD
> > from, a block was replaced automatically, just the way it's supposed to.
> > vis, I got a media error from reading one file, consistently, but it went
> > away after rewriting that file. Never crashed.
> 
> Hmm. It could be:
> 
> 1) NetBSD never re-writes the block, so it never gets remapped. Maybe it's
> in one of teh ffs overhead structures?
> 
> 2) Somehow block remapping got turned off. ??
> 
> As a test, if you can get netbsd to boot off of another partition, just
> zero out the whole file. I think copying /dev/zero to the raw partition
> will do that.

It appears to be set up to replace bad blocks (AWRE, ARRE, and RUEE all
set in the mode pages), but of course that doesn't mean it actually works.
The list of "user bad blocks" is empty. That's a great idea, zeroing every
sector from within NetBSD, but it will be months before I'm ready to do
that again. I've already made the big move, and now the other drives are
full of MacOS stuff. Thanks for the explanations. I think it's safe to say
now that there's nothing particularly wrong with newfs or Mkfs, and that
my observation is simply an odd coincidence.