In a previous non-Netbackup world, running on slightly older technology
(DLTs), 
I used to hoik tapes out of my then simple backup system and keep them in a
separate 
safe, every so often (e.g. once a month plus once a year) as a long-term
"archive"*backup,
on the "you never know when you will need it" principle.

(*not quite used in the Netbackup sense, I believe).

In the Netbackup world, on LTO technology, where I have multiple backup
images per tape,
this is slightly more complex.

Clearly, it's easy to select the backups images I want to keep, and extend
them to infinity (or whatever),
but that obviously takes a whole tape out of my system, and they don't come
cheap these days,
and it seems a shame to lose all that tape capacity for the sake of one
image.

What would be nice would be if I could copy off these selected images to a
separate archive tape or series
of tapes.

I know that bpduplicate can do this, but we already take a copy to protect
against bad tapes or
accidents, and Netbackup doesn't allow me to take another (3rd) copy (at
least not in 3.4).
(or strictly speaking, only allows one primary and one secondary copy, I
believe).

Now, I could extend my existing 2nd copy for "archive", instead of my
original, but I am still left with the problem
of only having one wanted backup on one tape, with the consequent waste of
capacity.

I suppose that once Netbackup expired my original primary, I could define my
copy as the primary
and then take a new secondary copy (to my "archive" series of tapes).
(I _think_ you can set separate expiry dates for primary and secondary,
though I don't
 quite remember the mechanism).

How would others approach this sort of problem?

With thanks,
Regards,
Mike Ellwood