Shawn and Gustin, thanks for the suggestions - I will take a look at netem. I did look use iperf and a few other tools like nuttcp and thrulay but couldn't reproduce the problem or get the network to fail.
The issue I am trying to troubleshoot is intermittent and random (the best kind!). I have so far managed to use tcpdump to capture the problem, but htis doesn't tell me what is causing it. I need ot get to the layers further down the model - Frame and Physical. I certainly cannot afford to buy one of those handy dandy network monitoring and testing tools, but I would be prepared to rent one or pay someone to test for me. On a related note - I didn't install the physical cabling and noticed on the managed switch that some of the ports are set to MDI and some others to MDIX - does anyone think that this could be an issue - I wouldn't think so as the switch is sensing the configuration, but you never know... Thanks Martin Gustin Johnson wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Since you have a linux network I would look into iperf, which should be > packaged in most major distros. mtr can be handy for locating problem > links. > > On a related, slightly OT note, you can simulate various kinds of > problems with these examples: > > http://linux-net.osdl.org/index.php/Netem > > Hth, > > Martin Glazer wrote: >> Hi, >> >> I'm experiencing some network issues and I'm trying to track them down >> - have run tcpdump and been checking logs, but to no avail. I suspect >> that there could be something now physically wrong with the network. The >> issues are intermittent. >> >> Does anyone know how I can go about testing the lower levels - what >> equipment do I need, can I rent it, is there a company in Calgary that >> does this? >> >> I know this is not directly related to Linux, we are running on a Linux >> network. >> >> Thanks >> >> Martin >> >> _______________________________________________ >> clug-talk mailing list >> [email protected] >> http://clug.ca/mailman/listinfo/clug-talk_clug.ca >> Mailing List Guidelines (http://clug.ca/ml_guidelines.php) >> **Please remove these lines when replying > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.6 (GNU/Linux) > Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org > > iD8DBQFG305pwRXgH3rKGfMRAqIUAJsErnHBV3E1+A2vA+7Pom1ji06L4QCdFF9v > LM63LSWk/GSp7GjOJkdFDzQ= > =yD/L > -----END PGP SIGNATURE----- > > _______________________________________________ > clug-talk mailing list > [email protected] > http://clug.ca/mailman/listinfo/clug-talk_clug.ca > Mailing List Guidelines (http://clug.ca/ml_guidelines.php) > **Please remove these lines when replying _______________________________________________ clug-talk mailing list [email protected] http://clug.ca/mailman/listinfo/clug-talk_clug.ca Mailing List Guidelines (http://clug.ca/ml_guidelines.php) **Please remove these lines when replying
