>   sd0: 2063MB, 8188 cyl, 3 head, 172 sec, 512 bytes/sect x 4226725 sectors
> but 8188*3*172 is 4225008 and not 4226725.
> Where do the extra 1717 sectors come from?

Welcome to modern disk drives.

The problem is that the disk geometry is not fixed - in particular, the
sectors-per-track value varies with cylinder number.  Most even vaguely
modern disks have this property.  The sectors-per-track value the drive
reports (172) is the total sector count, divided by 8188 and 3 (the cyl
and head values), rounded down to an integer.

> What is the correct number of total sectors?

4226725 is the actual number (unless you want to include spares and the
drive overhead sectors, which you almost certainly don't - particularly
since you can't normally use them).  Whether this is the correct number
to put any particular place, well, "that depends".  Coaxing a SCSI disk
to play nice with an Intel machine's BIOS is something I've never found
myself needing to do, so I will let those who know more than I speak to
that side of the question.

					der Mouse

			       mouse@rodents.montreal.qc.ca
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