Wireless Troubleshooting Instructions

This document provides a set of troubleshooting steps for users trying to get connected to the UCAR wireless network. There are many components to the UCAR wireless network; the following steps attempt to help isolate which one might be the source of the connection problems you may be experiencing. Following these steps will make it easier to find and contact the appropriate support group for rapid repair. Contact information is included at the bottom of this page.

Are you connected to the UCAR wireless network? You may be in an area which is not currently covered by the wireless network. It's also possible that you have connected to a non-UCAR wireless network. In some buildings that make up the UCAR campuses, especially CG4, there are non-UCAR wireless networks in the area which can be inadvertently connected to. Please check these items to determine if the connection to the wireless network is the source of the problem.
Windows users can find the information by clicking on the icon for their wireless network interface in the task bar and selecting the 'Status' option. Look under the "General" tab.
Mac OS X users can find the information by selecting "Open Internet Connect" from the Airport icon in the main menu bar.
- Have you enabled wireless connectivity?
  - Some laptops with built in wireless cards include a switch to enable and disable the antenna. If your laptop has a built in wireless card and includes this feature, please be sure you have the wireless enabled. Such a switch will probably be labeled "wireless" or may have a small antenna logo. In some cases, this feature is activated by a hot key combination such as Fn-F1. This is usually indicated by a small antenna logo on one of the keys on the keyboard. In Mac OS X the Airport menu in the menu bar includes an item for turning the Airport card on and off. If you are using a PCMCIA removable wireless card, this does not apply to you.
- How is the signal strength?
  - If your signal strength is low, you may be in an area with poor coverage. NETS works to provide full wireless coverage of UCAR spaces. Signal strength in major conference areas should always be good. In office space it is usually good but there are some areas and small pockets of weak coverage. Consult the coverage maps for your location.
- Are you associated to the "UCAR" network?
  - In Windows XP this information can be found under the "Wireless Networks" tab of the wireless interfaces "Properties" window. If you are connected to a wireless network which is not named "UCAR" please try the following steps:
    - Add the SSID of "UCAR" to your list of preferred networks.
    - Report the name of the other network to NETS for investigation by contacting NETS.
Did you get an IP address from the DHCP server? There have been problems with the DHCP server for the wireless network in the past. This will prevent you from getting a working IP address. In Windows XP, this information can be found under the "Support" tab of the "Connection Status" window for your network interface. In Mac OS X, open the Network section of System Preferences and select the TCP/IP tab.
- Does the address start with 128.117.[227,228,229,230,231]?
  - Yes, go to the next numbered step.
- Does the address start with 128.117.[something else]?
  - Contact NETS. You may be connected to an unauthorized access point.
- Try renewing your DHCP lease
  - Repair under XP, "Renew DHCP Lease" in Network section of System Preferences under Mac OS X.
- Does the address start with 169.254 or is it described as a "self-assigned" address?
  - If yes, the DHCP server may be misbehaving. Contact NETS.
Can you browse the Access Point pages? The wireless access points that NETS deploys have a web interface which can be viewed by users. By viewing one of these pages in your web browser, you can verify that you have a good connection to the wireless network as a whole. By seeing if this works by both name and address, you can verify that DNS appears to be working for you. Try typing the following URL's into your web browser's address bar:
- Can you browse by name? Check by going to "http://ml-47-c1-ap.ucar.edu"
  - Yes, go to the next numbered step.
- Can you browse by IP Address? Check by going to "http://128.117.231.2"
  - If not, it's not clear what the problem might be. Contact NETS so that they can investigate further
- By IP address but not name?
  - It's probably a DNS problem. Contact DSG.
Can you ping wireless.ucar.edu (128.117.228.250)? This is the name and address of the server which provides the web login page. This box must be working properly whether you are using the web login or the VPN server. Windows users should run the "Command Prompt" application found in the Start menu. Mac OS X users should run the "Terminal" application.
- Test if you can ping by name. Type "ping wireless.ucar.edu" into your "Command Prompt" or "Terminal" window. The ping will stop automatically after a few seconds for Windows users. Mac OS X users should type Control-C to stop the ping after a few seconds. The command will report the amount of packet loss. Is it zero?
  - Yes, move on to the next numbered step.
- Test if you can ping by IP address. Type "ping 128.117.228.250" into the window.
  - Yes, it's probably a DNS problem. Contact DSG.
- Pings fail by both name and IP address?
  - Yes? The problem is probably on sabae, the wireless gateway. Contact the CISL Network Operations Center.
Can you connect to the VPN server?
- Can you connect to the primary VPN server at 192.43.244.230?
  - Yes? Congratulations. It appears you are no longer having a problem.
  - No? Contact the CISL Network Operations Center, the VPN server may be the problem.

Wireless Troubleshooting Contact Information

Please open a CISL Request using this form or if an emergency, contact SCD Operations group at extension x1200 and identify the wireless problem specifying what group (NETS, DSG, Computer Security) the troubleshooting guide says can address the problem. Return to top of document.