>    Also, a 'q vol * f=d' will tell you how many mounts each volume has
>undergone, but only since it has been put into a storage pool, right?
>If the volume gets reclaimed back into a scratch pool and gets reused,
>then those numbers get reset.

True. You'd have to capture that info periodically, before it disappeared
as the tape was reclaimed. Otherwise, some libraries (e.g., 3494) keep
mount stats on volumes for as long as they are in the library.

As for the larger issue: The best approach may be to consider a tape ready
for retirement when it start showing correctable read errors.  Remember
that it's not just usage which governs life: a tape stored offsite could
get distressed by environmental conditions despite not being in use, and
exhibit problems when next used.
    Richard Sims, BU