RE: Migrating W2K3 to W2K3 server?

["Phil Harris" <phil@xxxxxxxxxxx>]

> No Worries!
> Just as a little thing to try - lock your network speeds to
> the highest your card / switch combination will go. (if your
> switch is 10/100mb and your net card is 10/100/1000mb - lock
> the card to 100mb). I'd heard from a 3com engineer a while
> ago that there was an inherit problem with the auto speed
> negotiation protocol (not just with 3com stuff - but
> generally) whereby under heavy load your link drops to the
> lowest common (which is usually 10mb half duplex!) without
> telling you about it. If you can lock the speed on your
> switch port too - all the better.
>
> That may be a bit of a 'climbing up the wrong tree' but its
> worth a check.
>
> Enjoy!
> Wayne.

I can definitely confirm that I've seen this happen with machines here at
home - I regularly copy *LARGE* amounts of data around the network here ...
between 5 and 40Gb at a time ... and I had noticed that sometimes my
transfer would suddenly be running dog slow with Task Manager reporting
that
it was using maybe 5% network bandwidth at best.

I went into network properties and set the connection type to 100mbits full
duplex and that sorted the issue (even though Windows already reported that
it was running at 100mbits) - network usage back to a fairly stable
74%-81%.

Strangely I use 3Com 905 cards in all my machines simply because the
support
for them is so widespread (i.e. whatever OS you whack on it it usually has
905 drivers) but I've never had this happen on any of my other brands of
network cards or the mobo built in network interfaces. (Mind you - I don't
use them very often so perhaps that's simply that I haven't been using them
enough for the problem to occur...) It wouldn't surprise me if it is a 3Com
problem though as the only times I've heard this reported is in conjunction
with machines running 3Com network cards.

Phil