Hi DU Admins
I only received one reply to my question about anomalous arithmetic
in a disk label for an rz29b under DU 4.0B. That was from Mike at
obrien_at_splusnet.com who reported the same problem under DU 3.2G
but he thinks only after he installed some patches.
My tentative conclusion is that this is a bug in the unpatched
DU4.0B disklabel and in some patched 3.2x versions.
I also got one reply to my second question about anomalous
arithmetic in a disklabel for an RZ1BB-BS with dynamic geometry.
That was from John Holden and this is his answer:
> I think that you are seeing and interaction of two things :-
>
> 1) High density disk drives use zone recording methods. This means
> that there are more sectors per track on outer tracks than on inner-
> tracks. There is no scope in disktab to reflect this properly, so
> that the sectors/cylinder is an approximation to allow some
> reasonable guesses for disk layout and cylinder groups.
>
> 2) The sectors/unit value (partition c) is actually read directly from
> the disk using a SCSI 'inquiry' command and reflects the actual
> number of blocks available. You could lie about the disk type
> when you create the disk label, but the value for partition c will
> still be correct.
Thanks
Ian
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
_/ Ian Mortimer _/
_/ Email: mortimer_at_physics.uq.edu.au ,-_|\ Department of Physics _/
_/ Tel : +61 7 3365 3436 / *\ University of Queensland _/
_/ Fax : +61 7 3365 1242 \_,-._/ St. Lucia, Brisbane _/
_/ v Queensland, Australia 4072 _/
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
Disclaimer: Any opinions expressed are my own.
Received on Tue Aug 19 1997 - 00:52:00 NZST