We would like to restore tapes older then 3 months but on those tapes even if we say inventory and catalog we are not able to see elements on this (however we can see the backup sets on this).
If we click on a server backup set and say restore as well as specifing the expected date there is a yellow triangle with an exclamation mark and tells us "Snapshot backup set partial".
Catalogs truncated after 3 months
We tried to check and uncheck "Request all media in the sequence for catalog operations" and "use storage-based catalogs" but I think it has nothing to do with the catalog.
Cheers and thanks
I cannot answer if the original reported issue ever got solved however I would suggest to see if either of these two methods helps you:
1. Move the tape to retired media and then delete it.
(This will not delete any data on the tape, just the tape reference itself)
Afterwards rerun the inventory followed by catalog
2. See if you can duplicate the data / backup set to disk and then try the restore from disk