How to Diagnose Network Issues

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Basic Troubleshooting

So, your computer seems fine, but your "Tetris Online" game won't open. Perhaps you don't have a network connection. Here's a couple of things you can do to help determine the nature of the problem. First, open a web browser, like Firefox, Safari, or Internet Explorer. Try something basic, like www.google.com.

Don't see anything? Get a "Server not found" or "The page cannot be displayed" error message? Look to see if you have a network link signal. Many systems will show a green "link light" nearby the network connector on the back or side of your computer. Mac users will have to check the Network Page in System Preferences ("Show Network Status") to see if your connection is active. Windows can also give you an indication if the cable is unplugged or not, try opening the Network Connections Control Panel to see what's there. Make sure no connections are marked as "Disabled," if so, you can change that setting right there in System Preferences or the Control Panel.

Wireless trouble? Try connecting to the ObieWiFi network again. If no networks are listed, try disabling your wireless interface and re-enabling it again. Our wireless covers most of the campus pretty well, but you might have found one of the few remaining spots where the signal is too weak. Try testing things in a different location.

Trying to use a wired connection? Network ports are not active by default in residence hall rooms, so send an email to our Help Desk to activate it. We'll need to know your residence hall and room number, as well as the number or letters describing the wall jack which isn't working (if applicable). We also require a phone number so our staff can contact you to set up a time to activate and test your port.

Information we would like to know

  • We need to know how to find you: Residence Hall, room number, phone number and/or email, please.
  • We need to know the problem symptoms, and the results of the tests you've performed already, including the ones above.
  • It's really helpful to know the IP address and MAC address of the computer, if you can get them.
    • In Windows, the command line is quickest
      • Click Start, select Run, type in "cmd" and click OK.
      • In the (usually black) window, please type "ipconfig /all" and press the Enter key
      • Lots of information comes back. Please send the text from every "Physical Address" and "IP Address" line you see.
    • In Macintosh, use the Network panel in System Preferences. Show each interface in turn (probably Built-in Ethernet and AirPort), and click on the TCP/IP button for the IP Address, and the Ethernet button for the Ethernet ID.
  • Finally, please tell us when it's convenient or best for us to reach you. Someone will be in touch with you promptly.


Testing Your Connection

If you have a network connection, but it seems to be amazingly sluggish, you may still have a problem with your computer and not with the network. To help us determine the location of network slowdowns, we've located several Network Diagnostic Tools around the campus network. You can run a connection test with any of these servers:

Network Diagnostic Tools around campus
South Firelands Language Houses
Campus Mudd Central Peters Hall Severance Hall
North Burton
Between us and the World
On our router At our edge In Columbus, our ISP
On Abilene, the Internet 2 Network
Indianapolis New York Seattle
Sunnyvale, CA | Washington, DC
Other available servers
Argonne National Lab U of Michigan, Flint UC Santa Cruz
Stanford NSF, Arlington, VA Jefferson Accelerator Lab
Swiss Education Network | U of Hawaii


Ndtscreen.jpg

For a rough indicator of off-campus performance, many of us consult the bandwidth speedometer at Speakeasy. Mostly we choose the Chicago server, for comparison. You'll need the Flash plug-in for your browser for this test to display properly.