On Mar 6, 2006, at 2:03 PM, LeBlanc, Patricia wrote:

Okay so if my port on the switch is 1000/full as well....could it be
we're sending the data to tsm too fast?

Though you would expect normalcy and standardization to prevail in
this modern age, networking interfaces are distressingly
unpredictable across brands these days: you never know what's going
to happen when you connect Brand A to Brand B.

An example: We recently acquired IBM 2105ES printers to replace our
old, non-ES models. So we connected them to the same 100 Mbps-full
switch ports we'd always used, and configured the printer end the
same as usual. The result: astoundingly bad throughput. We referred
the matter to IBM, and were put through a solid week (and weekend) of
wasting our time with lower-level people, until we were finally
handed over to development types who actually knew things. Here it
became known that the printer controller (now externalized in a black-
box PC) was using a network card we had never heard of, and which
acted as oddly. Though the printer and switch were set to 100 Mbps-
full, the printer controller network card was performing as half-
duplex, making a mess of the packet traffic. Against our better
instincts, we had to change to auto-negotiation - whereupon the
foolish printer network card would THEN operate at 100 Mbps-full. Go
figure.

It is sometimes the case that network interfaces make no sense, and
you have to start with a rational setting and then depart from that
until you find a combination that works, and document it and stick
with it. It's all about dealing with idiosyncratic designs.

    sigh, Richard Sims