jmaier@midamerica.net apparently asked:
...
> The 2nd dump on the tape is /var (it's own partition) and the man page
> doesn't give any obvious clues as to how to forward the tape to the point on
> the tape where that dump starts.
>
> Any words of wisdom?

At risk of Thor castigating me if I make any errors in my statements
here, I will carefully note that the:

mt -f /dev/nrst0 rewind 

command will rewind your tape to the beginning.  (I'm not sure where
you are on the tape already, so starting at the beginning may be a
good idea.)  Then the:

mt -f /dev/nrst0 fsf 1

will move your tape position forward one file.  I believe this may
take you to the file you want (since it's the second dump, it might be
necessary to use "mt -f /dev/nrst0 fsf 2" instead).  If not, you can
repeat the preceding command to get to the second file.

I apologize in advance for any inaccuracies contained in this message.
I have done my best to confirm the facts with the man pages, but am
working from my memory of several years back about how to control
tapes for backup.  This is, however, a sincere attempt to be helpful.

Regards,
James Wetterau