need to set automatic overwriting of LTO tapes

[Matt26]

hello all,

i currently back up a number of folders on one of our servers (over 200GB of data) on a daily basis to LTO tapes (using HP C7972A 400GB tapes).

i have 10 tapes in total that are used in a 2 week rotation.  what's happening is that i put a tape in for a nightly backup, and i come in the next day to see that the tape is ejected and another tape is required- i'm guessing because the tape being used is full.

my question- is there a way to have the backup jobs automatically overwrite the tapes so that the jobs don't require another tape to complete the job?

i thought i had this set up but now some days the backup will complete without prompting for another tape, but some will not- in both cases the tapes have data on them.

any help is greatly appreciated.

thanks for your time!

[Donald_Eady]

How many backup jobs are you running at night? 

Are the jobs set to eject the tape after the job/s complete?

what are you OPP and APP Set to?

And how are you jobs configured to Overwrite or append?

[Colin_Weaver]

I hope you have 13 days Overwrite Protection set and not 2 weeks as the OPP is taken from the end of the previous job and the choice of what is overwriteable is made at the start of next job meaning 2 weeks would be too long for a 2 week rotation.

[pkh]

When you set the OPP, check that the tapes are overwritable BEFORE the next run of the job.