On 3/2/10 2:49 PM, Jarvis, Matthew wrote: >> -----Original Message----- >> From: [email protected] > [mailto:[email protected]] >> On Behalf Of James E Harvey >> Sent: Tuesday, March 02, 2010 2:29 PM >> To: [email protected] >> Subject: [NF] network traffic software (free preferable) >> >> >> My question is, is there any free software that will "find" which > device >> is >> going bad and sending out bad packets, if that is the problem? >> > > The most dreaded words in IT: "the network is slow".... talk about > time-suck trying to track this one down.... ;) > > If it isn't an intermittent thing i.e. when it gets bad, it STAYS bad, > you have a shot at tracking it down with free tools you already have: > tracert and ping. > > First tracert to the router and get the list of IP addy's. > > Then from you desktop, ping up the chain waiting to see slow times. It > helps if you can telnet/connect to the devices in line between you and > the router to help narrow/confirm your search. > > It would be nice if you could do the tracert/ping test when the thing is > acting correctly to get a benchmark.
I like to ping flood each device to see which stop responding under load. Obviously, do this when users aren't trying to work. I don't think Windows ping has the -f switch, but you could boot a Linux live distro, sudo to root, and then: ping -f <hostname> Here's the output pinging my server (server is in Southern California; I'm in Central California) - I'm on a Mac: bash-3.2# ping -f paulmcnett.com PING paulmcnett.com (208.70.74.99): 56 data bytes ..............................^C --- paulmcnett.com ping statistics --- 5172 packets transmitted, 5142 packets received, 0% packet loss round-trip min/avg/max/stddev = 23.894/26.981/59.256/3.437 ms bash-3.2# This was about 10 seconds of flooding. I like how it gives good stats at the end including not just average but standard deviation. If you see wildly different numbers for min and max on your local network for some device and not others, that device could be the culprit. I've had a few switches cause huge network lags. If the switch isn't managed (doesn't have an ip of its own to ping) then you'll have to use trial and error. One of my switches would work for a couple days and then totally hang. When I finally figured out which switch this was, I took it out back and beat it with a baseball bat. Paul _______________________________________________ Post Messages to: [email protected] Subscription Maintenance: http://leafe.com/mailman/listinfo/profox OT-free version of this list: http://leafe.com/mailman/listinfo/profoxtech Searchable Archive: http://leafe.com/archives/search/profox This message: http://leafe.com/archives/byMID/profox/[email protected] ** All postings, unless explicitly stated otherwise, are the opinions of the author, and do not constitute legal or medical advice. This statement is added to the messages for those lawyers who are too stupid to see the obvious.
