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elhombre
Asked: 2010-07-02 13:29:02 +0800 CST

network timeout how to analyse problem

  • 772

In the last three month I was experiencing that my internet connection started to get very slow and websites had long time to load. The first thing I made was an ping to www.google.com which showed that I was loosing pakets. Here some of the results:

64 bytes from 74.125.39.103: icmp_seq=2909 ttl=53 time=48.222 ms
Request timeout for icmp_seq 2910
Request timeout for icmp_seq 2911
64 bytes from 74.125.39.103: icmp_seq=2912 ttl=53 time=44.372 ms

Days later I had to reset my router because it wasn't able to establish a correct network connection. It was after the reset when things worked again for some days. But later the same network timeouts started to happen again.

I would like to know how I can analyze the problem to get to the source which is causing this timeouts. Which steps do you take to circle in this Problem?

My Network
Laptop -> Wireless Router modem -> ISP

EDIT: I am on a Mac OS X 10.6

connection network-monitoring timeout

5 Answers

  1. Look at using mtr on your OSX system.

    It is very helpful tool that repeatedly does a traceroute, storing the information about each hop along the way.

    So, in the end, you have a list of the "x" number of hops, their availability/packet loss and average, min, and max ping times.

    Syntax for "interactive" mode is simply 

    mtr <site>

    or for easier offline analysis, 

    mtr <site> --report -c 1000

    You can get info on how to install mtr from: http://mtr.darwinports.com

    Sample output: 

    $ mtr google.com --report -c 10
HOST: blahblahblah                Loss%   Snt   Last   Avg  Best  Wrst StDev
  1. h119.127.19.98.static.ip.win  0.0%    10    5.4  14.4   2.0 111.1  34.0
  2. h235.30.213.151.static.ip.wi  0.0%    10    3.4   3.7   2.0   8.4   1.9
  3. h122.222.90.75.static.ip.win  0.0%    10    3.3   4.0   3.3   5.7   1.0
  4. h18.222.90.75.static.ip.wind  0.0%    10    3.9   4.5   3.4   5.5   0.7
  5. h16.222.90.75.static.ip.wind  0.0%    10    5.1   6.1   5.1   7.5   0.8
  6. h38.254.213.151.static.ip.wi  0.0%    10    6.7   7.3   6.2   8.8   0.9
  7. h14.254.213.151.static.ip.wi  0.0%    10   23.9  25.0  23.4  31.1   2.4
  8. h12.254.213.151.static.ip.wi  0.0%    10   23.9  24.8  23.3  27.3   1.1
  9. h10.254.213.151.static.ip.wi  0.0%    10   41.5  42.0  41.3  43.4   0.7
 10. 72.14.219.192                 0.0%    10   41.0  46.6  40.8  88.3  14.7
 11. 72.14.233.54                  0.0%    10   42.9  54.3  41.3 157.1  36.2
 12. 72.14.232.213                 0.0%    10   44.5  42.8  41.3  45.3   1.4
 13. 209.85.253.141               40.0%    10   50.5  51.4  48.6  55.8   2.5
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  2. Use traceroute (tracert in windows) against Google. This effectively gives you the latency to each hop between you and Google, and will give you an idea if it is your router, or further upstream.

    • 2
  3. Best Answer

    Call your ISP. They can be surprisingly helpful.

    • 2

  4. First off, use a traceroute. Assuming you're using Windows, it's tracert www.google.com.

    You may have to do several, but it will show how far your packets are going before they fail to get a response.

    There's a good chance that you're going to have intermittent packet loss, which makes troubleshooting a massive PITA. It may help to A) Try your laptop connected directly to the cable modem, B) try a wired interface on your router, and C) try a different network entirely.

    This helps determine if its your router (A), WiFi (B), or ISP/Cable Modem (C).

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  5. We where having problems with out of our Comcast business connections to a small site. Comcast was not very helpful when we contacted them because we didn't have data. Showing the problem.

    So we setup a instance of smokeping and set it up to something on the comcast network a few hops away. We showed the smokeping graph to Comcast which was pretty consistently showing 10-15% packet loss. They tried lots of things, but eventually they discovered the wire between the poll and the building was bad. The point here is that you may need to collect a lot of data over time and graph it. A simple trace route may not be enough. Particularly if the issue is intermittent.

    Of course please start off by doing the obvious and watch your connection to make sure you don't have any malware or crap on your machine that is saturating the link.

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