Limit the amount of tapes for copypool in library

mosiac

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PREDATAR Control23

Is there a way for me to tell a copy pool to only keep say 10 or 15 tapes in the library for read write access at a given time?

Should I adjust my command that sets "offsite" status for tapes from 7 days to 5 or lower? Or is there a better way?
 
PREDATAR Control23

Why do you have to keep offsite (copy pool) tapes in the library?

The default procedure is to eject offsite tapes right away after completing the copy from the online tape pool. This is your DR path.

Imagine what will happen if you keep the tapes and the Data Center that houses the tapes suffered from an unrecoverable disaster? You then lost all of your data.

If you MUST do this, then just don't eject those tapes for the duration that you want (again, defeating the purpose of offsite copies).
 
PREDATAR Control23

The way it was previously setup was that it would check out any copypool tapes that were today-7 and the same for expiring data that was on old copy pool tapes, they would go into expiration but take 7 days to completely be cleared of all their data ready for scratch again.

I'm not sure why this was done but I would be more than happy to pull out all my copypool tapes on a daily basis but I don't know if I'll accomplish getting much written to them per day that way.
 
PREDATAR Control23

The way it was previously setup was that it would check out any copypool tapes that were today-7 and the same for expiring data that was on old copy pool tapes, they would go into expiration but take 7 days to completely be cleared of all their data ready for scratch again.

I'm not sure why this was done but I would be more than happy to pull out all my copypool tapes on a daily basis but I don't know if I'll accomplish getting much written to them per day that way.

You don't worry if the copy tapes are just 1% or 90% utilized. What you should worry about is protecting your data.

Eject the tapes daily and you would get them back as scratch via reclamation.
 
PREDATAR Control23

The way it was previously setup was that it would check out any copypool tapes that were today-7 and the same for expiring data that was on old copy pool tapes, they would go into expiration but take 7 days to completely be cleared of all their data ready for scratch again.

Ok, so you have a reuse delay. The purpose of a reuse delay is that tapes are not overwritten for X days, which means that if you were to restore the TSM DB to a previous date (up to 7 days in your case), the data would still be available on the tape.

That's not the default, but it does provide extra protection. So you have to do a cost VS risk analysis. Is getting these tape immediately more important to you than the risk of loosing data if you were to be forced to restore the DB to a few days ago? If the answer is yes, then you can get rid of the reuse delay.
 
PREDATAR Control23

BTW, the customers that do use a reuse delay typically do so on their primary pool only, not their copy pool. But nothing says you can't do both. Again, cost VS risk.
 
PREDATAR Control23

Honestly at this point I'd like to be able to feel like I've actually got all the data I'm supposed to be backing up. Right now I'm trying to find a way to clear out space in my library to add new scratch tapes so that I can write more data. I'm still working through another issue thread where for some reason some of my backups are trying to go straight to a tape stgpool versus disk first and I don't understand why at all.
 
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