> I'd just like to finally get to the bottom of this kind of statement. I
> believe it to be
> popular myth!  I too also believed that excessive cleaning of DLT drives
> would
> increase headwear however I've recently been told categorically by an STK
> trainer
> that a DLT cleaning tape is simply a standard tape that has not gone
> through the
> burnishing process. As such it's a standard tape (same thickness, same
> material) > as a data tape only not polished. Since it's movement over the
> heads is identical

A DLT tape drive is typically described as "self-cleaning", and as such
should only be cleaned when it actually requests it.  Excessive cleaning
beyond this does increase head-wear -- just ask your STK CSE.  They won't
enjoy flipping drives due to head wear because you're cleaning the drives
too much.

Prior to NBU 3.2 (and with other backup products), the normal recommendation
was to ensure that the robot did the drive cleaning when the tape drives
asked for it, and not to schedule it through the software (which only
understood the N hours of usage rule).  This had the drawback that the robot
might be sitting there with a used DLT cleaning tape waiting for a
replacement to be loaded, with no operator notification.  If mount timeout's
were too short, a drive could also inadvertently get marked down by the
software, due to the robot's issuing a drive cleaning.  As well, only some
vendors robots supported self cleaning options.

I haven't played with the NBU 3.2 feature for properly detecting drive
cleaning and managing it itself -- if it works well, it means that you can
now at least monitor cleaning tape usage and trigger an appropriately timed
action.

And as a final point, cleaning a drive every "N hours" when it doesn't
really need it also costs you extra $$.

Cheers,

Mike


Michael Traves              mtraves AT esitechnologies DOT com
Senior Architect
ESI Technologies           www.esitechnologies.com