UDF and sector size

[tlaronde%polynum.com@localhost]

Hello,

I use a NetBSD (5.1.2 on amd64) to serve files (via NFS or Samba) and to
do backups.

I have put a first backup internal to the server (via 2 disks) and I do
an external backup via the network. But the appliance used for this
"remote" backup has problems and I need to find another way.

I would like to be able to do a backup on an USB attached disk, so that
this backup can be... detached (and stored away) but, in case of 
disaster, what will be on one of these USB attached disks should be 
able to be read by Windowes nodes.

It seems that the only possible filesystem (I would prefer a "raw" disk,
not another "server" so no NFS or CIFS or whatever service) is UDF
since, if I understand correctly, it should be recognized by both
NetBSD (and other BSDs) and Windows (and Mac, but there is none
there).

By a cursory reading of the spec for 2.01, the logical size has to
be the physical size of the media. newfs_udf(8) does not allow to
specify the sector size directly (but probably by using vnconfig
it should be possible to create a customary sector size) but some
data found on the Web seem to indicate that Windows will "prefer"
an HD formatted with 512 bytes sectors.

Has anybody any info/experience about that, and about sharing UDF
between NetBSD and others?  Since the extent of the file is given to
be 2^30 logical size blocks, there is no great limitation even with a
512 bytes block disk---I mean a 2 To disk could be formatted with UDF?

TIA
-- 
        Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
                      http://www.kergis.com/
              http://www.renaissance-francaise.fr/
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