Actually, I've discovered the problem and filed a PR about this:

    http://www.netbsd.org/cgi-bin/query-pr-single.pl?number=26636

Anybody got a fix?

cjs
-- 
Curt Sampson  <cjs@cynic.net>   +81 90 7737 2974   http://www.NetBSD.org
    Don't you know, in this new Dark Age, we're all light.  --XTC

On Fri, 13 Aug 2004, Curt Sampson wrote:

>
> Anybody know how to put a filesystem on to a DVD-RAM under
> NetBSD-2.0_BETA/i386? It's a fine 2048 byte per sector block device, and
> I can disklabel it, but newfs doesn't seem to like it.
>
> dev1 # disklabel cd0
> disklabel: Can't read master boot record 0: Invalid argument
> # /dev/rcd0d:
> type: ATAPI
> disk: dvdram
> label: dvdram
> flags: removable
> bytes/sector: 2048
> sectors/track: 100
> tracks/cylinder: 1
> sectors/cylinder: 100
> cylinders: 22368
> total sectors: 2236704
> rpm: 300
> interleave: 1
> trackskew: 0
> cylinderskew: 0
> headswitch: 0           # microseconds
> track-to-track seek: 0  # microseconds
> drivedata: 0
>
> 4 partitions:
> #        size    offset     fstype [fsize bsize cpg/sgs]
>  a:   2236700         0     4.2BSD   2048 16384     0  # (Cyl.      0 -  22366)
>  d:   2236700         0     unused      0     0        # (Cyl.      0 -  22366)
>
>
> dev1 # newfs -S 2048 /dev/rcd0a
> /dev/rcd0a: 4368.6MB (2236700 sectors) block size 16384, fragment size 2048
>         using 24 cylinder groups of 182.03MB, 11650 blks, 22912 inodes.
> wtfs: write error for sector 2236699: Invalid argument
>
> I do seem to be able to write the block:
>
> dev1 # dd if=/dev/zero of=/dev/rcd0a bs=2048 skip=2236699 count=1
> 1+0 records in
> 1+0 records out
> 2048 bytes transferred in 0.002 secs (1024000 bytes/sec)
>
> cjs
>