Yes and no.  I wasn't generally splitting streams across drives.  I
could easily fit 6 clients on a single DLT IV media, not counting the
mail server but it had it's own class anyway, so I wasn't getting
multi-tape problems.  I was seeing this transfer rate within a single
tape, no changing was ever done.

My copy was a one drive to one drive ration, one read and one write.
But as I said, no tape change ever took place on the clients I used to
test.

~JK

> 
> When using MPX, you're splitting the stream across multiple drives.
> Did you have multiple drives available (and occupied) by the MPX'ed
> tapes that were being copied to the non-MPX offsite?
> 
> I'd imagine that if you had, say, only one drive available on the
> "read" end of that copy, the library would be spending an awful lot of
> time changing between tapes, seeking, and rewinding.  That scenerio
> could certainly explain seeing such low throughput.
> 
> -brian.