non-invasive alternatives to netperf

In my network benchmarking adventures so far I've found netperf to be an
excellent tool. But the point is, netperf is "invasive" in the sense that
it is generating its own traffic to monitor my network. Are there any
similar tools that will just allow me passive network traffic / bandwidth
monitoring?

I want to load my cluster with its typical workload and then as a
uninterfereing "observer" see if the network is running to its full
capacity or not. IS there another suite of tools I ought to be
considering?

--
Rahul

In comp.os.linux.networking Rahul <(E-Mail Removed)> wrote:

> In my network benchmarking adventures so far I've found netperf to
> be an excellent tool. But the point is, netperf is "invasive" in the
> sense that it is generating its own traffic to monitor my
> network.

It can be very invasive indeed! I once got a call from some
distressed folks - seems that they had a developer mess-up his routing
and so netperf UDP_STREAM tests were flowing over an intra-site link.
That would have been ok for a little while, but it persisted - long
enough to rather toast the security camera feeds from one site to the
other It was after that phone call "Them: Can't you do something in
netperf to prevent that? Me: Nope" that I started putting "netperf" in
the default buffers being sent - at least then it is a little easier
to notice

> Are there any similar tools that will just allow me passive
> network traffic / bandwidth monitoring?

Most switch vendors, HP ProCurve is an example, offer tools to provide
nice pretty pictures of load on their switches/ports - the "managed"
ones anway. IIRC free versions can arrive on a CD with the switch and
one can buy more advanced versions.

http://www.hp.com/rnd/products/management/index.htm

has links for both flavors for ProCurve switches.

Some folks will use the mrtg (multi-router traffic grapher iirc) to
make pretty pictures of similar stats retrieved via SNMP.

rick jones
--
oxymoron n, Hummer H2 with California Save Our Coasts and Oceans plates
these opinions are mine, all mine; HP might not want them anyway...
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...