Netbackup - How do I expire, delete tapes from the database?

First you need to make sure that there are no valid images on the tape that you want.
NetBackup\bin\admincmd\bpimmedia -mediaid -L

If there are no images that you need, expire the tape:
NetBackup\bin\admincmd\bpexpdate -m -d 0 -host -force
This expires the images in the media database which resides specifically on the media server.

Verify that the images have been expired by re-running:
NetBackup\bin\admincmd\bpimmedia -mediaid -L

Now make sure that the tape is deleted from the volume manager on the master server. This step is automatically run by Veritas twice a day, and if you have used bpexpdate the tape will be removed but you can force it to take effect immediately:
volmgr\bin\vmquery -m
This gets some information on the tape such as its assigned date, pool number and status. If the status is anything other that 0×0, that issue needs to be resolved first – The most likely issue is a Frozen tape – IT must be unfrozen before you deassign it.

To unfreeze a tape:
NetBackup\bin\admincmd\bpmedia -unfreeze -m -h
If the tape was suspended you can replace -unfreeze with -unsuspend

If you are unsure which media server the tape belongs to:
NetBackup\bin\admincmd\bpimmedia -L -mediaid

This step will deassign and remove the volume images.
Volmgr\bin\vmquery -deassignbyid

Finally delete the tape:
volmgr/bin/vmdelete -m

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