On Wed, Feb 25, 2009 at 5:23 AM, Marcy Cortes
<[email protected]> wrote:

> Does look like z/OS guys can read stuff off after a formatting write
> though.  They told me they found addresses and other such corp
> properties data with their utility (DSS?)
>
> So probably not good enough for Alan  :)

Could this be an issue with the DASD subsystem being less than perfect
in emulating the behavior of a real disk? It is normal to wipe out a
track by writing a single record on it (and even let the device add
the remaining X'00' to avoid wasting transfer time). Normal channel
programs should not be able to look beyond that layer.

There's probably diagnostic CCWs that look further, but you would
restrict access to those tools. They could also read your data just
before you tried to format the T-disk. In your place I would probably
ask them who authorized them to use those tools...  Formatting of
unused disk space is to prevent the general user from getting access
to things.

The reason we talk about methods for planned complete data erasure is
for when the device is moved to a place where those restrictions do
not apply anymore.

Rob

Reply via email to