Happens to me too, and it is a managable situation.

Look carefully for unavailable or readonly tapes. Watch I/O errors. I
once had a flaky drive, and it would mount a scratch tape, start to
write on it, have an I/O error, make it readonly, and mount another.
This consumed 25 scratch tapes in only a couple of hours, and then none
were left and it was a crisis. (during a vacation, of course) You need
to track all tape I/O errors, so you can identify either media or drives
that are going bad and need to be replaced.

Our reusedelay is set to 2 days, and I know I can always delete any
pending tapes that became pending before the most recent database
backup. This is my emergency scratch tape supply.

I am currently managing a very full library, and I am finding that I can
always keep scratch tapes available by limiting MAXSCRATCH to less than
library capacity. This causes the gradual elimination of collocation as
the library fills, but it keeps the lights on until the library can be
expanded. I tweak MAXSCRATCH frequently.

With some effort, full library situations can be managed. I've been
doing it for quite a while due to delays in approving upgrades.

Roger Deschner      University of Illinois at Chicago     rogerd AT uic DOT edu
               Academic Computing & Communications Center
==== "NO OVERNIGHT CAMPING AUTOMATIC SPRINKLER SYSTEM IN OPERATION" ====
==== --sign, I-70 rest area, Parachute, Colorado =======================




On Fri, 1 Jun 2012, Richard Sims wrote:

>As an administrator, you need to perform the following regularly:
> 'Query Volume ACCess=UNAVailable,DESTroyed'
> 'Query Volume ACCess=READOnly STATus=FIlling'
> 'Query Volume ACCess=READOnly STATus=EMPty'
> 'Query Volume STatus=PENding Format=Detailed'
>to find tapes which TSM has given up on, as per messages like ANR1411W.
>Also check for tapes which may have been dedicated via Define Volume and which 
>might be put back into the scratch pool.
>This is to say that you may be artificially out of immediately usable scratch 
>tapes, but that potentially usable tapes may be identified and rendered 
>candidates once again.
>
>You should not check primary storage tapes out of a library except in dire 
>circumstances, and then judiciously.  Capacity planning monitoring should be 
>in place to anticipate the need for more library resources in advance of 
>exhaustion.
>
>    Richard Sims
>