It is possible to span tapes when doing a catalog backup...see
www.backupcentral.com FAQ:

        http://www.backupcentral.com/cgi-bin/netbackup-fom?file=175

The import process recreates the catalog entries.  Multiplexed tapes are not
a problem 
(I don't know about NDMP, but I don't see why not).  If an image spans
multiple tapes, 
then obviously you'll need all the tapes ;) To import, you do a "Phase 1,"
which is a 
quick list of the images on the tape - maybe 45-60 mins for a DLT IV tape 
(35Gb native/70Gb compressed).  After this you know which clients, dates,
etc., but no
file list information.  To actually import the tape, you do the "Phase 2,"
where NB reads each file in the backup, learns its metadata info, adds it to
the catalog, etc.  That is 
the long part...may 6-8 hours a tape for DLT?  Not bad if you have a low
priority request for an old media somebody hands you...but I wouldn't want
to do it in a DR situation ("the data center just melted and here are the
offsite tapes...oh yeah, I forgot to make a database tape to go with it, so
can you just import them, right? I think there's only 100 here...")


--
Drew Fabbro
fabbro.andrew AT cnf DOT com 
Desk: 503-450-3374    Cell: 503-701-0469
"There is no such word as 'maturity'.  There
is only 'maturing' and 'dead'." -- Bruce Lee