[Sunhelp] How to Low-Level format a SCSI Drive

[James Lockwood]

On Mon, 7 Jun 1999, Richard E Ravich wrote:

> Sometimes, if you start a format running and interrupt the formatting
> process before it conpletes, the drive will revert back to what the
> default value.  I must warn you, that you might make the drive into an
> anchor by doing it, but it may be worth a try.  

More often then not, the drive will enter a "degraded" mode until another
format successfully completes.  Not a good way to go.

> There is another way to reset the sector size by invoking format with the
> expert switch set.  Then you can actually configure a mode select command
> and send it to the drive.  It isn't impossible to do, but you'll need to
> spend sometime reading the SCSI spec to determine the correct parameters
> for the drive.

This is true, but to take the easy way out, I highly recommend that the
original poster download sformat:

ftp://ftp.fokus.gmd.de/pub/unix/sformat
ftp://ftp.fokus.gmd.de/pub/unix/kernel/scg

http://www.fokus.gmd.de/research/cc/glone/employees/joerg.schilling/private/index.html

(you will also need the scg kernel driver to run sformat under Solaris)

It's by Joerg Schilling, of cdrecord fame.  It can do some amazing tricks
with drives, and I've used it to fix very similar problems to what's been
described.  Think of it as a "super enhanced power-user format".

In addition, the sd driver at the same site _may_ let you use the disk
with 520-byte sectors as-is.  It's been a long time since I've tried it,
though, I don't remember if it only supports sizes that are multiples of
512.

-James