Scratch Tapes

[OKTSMGURU21]

I am having a DIFFICULT retaining scratch tapes in my LTO. I have done several things to try and resolve this:
1) drop the reclamation threshold
2) turned COLLOCATION on several storage pools
3) manually ran MOVE DATA commands on low-util tapes daily

None of this seems to be yielding high results.

Could someone PLEASE help me understand what I am doing wrong, and ways to fix this ?????

It would be GREATLY appreciated

 

[mbourne2006]

Hi

Do your tape barcodes run in an ordered sequence? If so, try the following:

1. Generate an ordered list of all volumes recorded in your TSM database. I use "q drm" and "q libv".

2. Generate a vault report that shows the labels of all volumes in your offsite facility.

3. Compare the two lists, look for gaps in the output from (1) that appear in (2). E.g. tape00-tape10 appear in both lists, but tape11 is only present in list 2. This tells me that I have an offsite volume that TSM does not know about. When I return the tape to the library, I can check it in as a scratch tape.

HTH

Matthew

 

[ProbablyDown]

How many scratches are you going through daily and how much data is being backed up?

 

[LED888]

Space reclamation should be set some were between 60 and 75. Higher the value reclamation is not going to run that often but you will get more scratch tape in return.
Lower the value, reclamation run more often but you would not get many scratch tape in return.

" turned COLLOCATION on several storage pools"
Not sure which stg pool that we turn collocation on, if its the tape pool then we have increase scratch tape usage.

Check your copy group setting.
Are we keeping too many versions for too long?

In the tape pool do we have the reuse delay set?

Are the nodes backing up more data than normal?

Have we added more nodes backing up to the TSM Server?

Good luck,
Sias