Here is the error msg that TSM generates with a defective tape drive (or media) 
:
Message
ANR8778W Scratch volume 343UTLL3 changed to Private Status to prevent re-access.

Tape robots are fast.   Ours marked all 134 of our tapes as Private at a rate 
upwards of 5 per minute on a weekend overnight shift.  

Ben Alford 
IT Manager, Office of Information Technology
Systems: Shared Services

The University of Tennessee
Room 118, Kingston Pike Bldg.
2309 Kingston Pike
Knoxville, TN  37996-1714
Phone:  865.974.1600





-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of 
Sims, Richard B
Sent: Wednesday, January 28, 2015 9:12 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: [ADSM-L] req: tsm db backup completed with failure and taking all 
scratch tapes fro DB BC

The simple answer is that you have to provide scratch tapes, else your TSM 
system will be crippled. Look around your system. Examine the Activity Log for 
the past week. Find out what has been happening to your scratch tapes. Look 
particularly for lots of tape volumes in Filling status and in ReadOnly state, 
where that is commonly caused by a faulty tape drive generating I/O errors. If 
tapes look healthy, then you may have a capacity planning issue in 
accommodating data influx growth.

   Richard Sims