Hot Diggety! Seay, Paul was rumored to have written:
>
> Suppose when the tapes were labeled the drive that labeled them was bad and
> now none of the drives can read them.

I had that issue pop up while setting up the 3584, and the culprit
was when the /dev/rmtX and element ID mappings had fallen out of sync.

End result? TSM loaded tape by element ID, then tried to access drive
via its incorrect rmtX mapping -- so it hit on a drive that didn't have
the tape loaded, got a read/open error, moved the tape back to its storage
slot (via element ID), marked it as Private in the TSM db, and repeat for
the next tape endlessly until TSM finally timed out this entire process.

Fixing the mappings instantly fixed that particular problem.

So I'd be more inclined to think that or some issue with DEVCLASS definition
was the culprit since one of the original poster's key words were '...all
tapes' -- if it was a bad tape, would have been an one-off.

-Dan