Commands by andrewgearhart (1)

  • Ping your gateway at home

    I run into regular problems whereby my cable modem from my ISP will simply stop working. To ensure that it is a problem with my cable modem (and not the router in-between my machine and the cable modem), I needed a quick way to test to someplace beyond the cable modem. The place shouldn't be beyond the cable network though. As such, I needed to determine the gateway to which my cable modem was connected. Since my router cannot do this on it's own... I created a single line command that will ping the gateway IP address based upon knowing that my gateway will be my second hop (after my wifi router), tracerouting for 2 hops, pulling the last line of the traceroute output and grep'ing for just the IP address. To stop pinging, use . This works on linux and osx and, with the addition of cygwin tools or the win-gnu project... should work on windows as well. Show Sample Output


    0
    ping `traceroute -m 2 8.8.8.8 |tail -1|grep -E -o "([0-9]{1,3}[\.]){3}[0-9]{1,3}"`
    andrewgearhart · 2015-03-25 19:55:54 74

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