Wifi Troubleshooting Guide

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Is the wifi hotspot dot visible?

In the Neighborhood View, you should clearly see your wifi hotspot's network name. If you cannot see the network name...

hidden SSID

Is your SSID/Network Name Hidden? This makes it impossible (currently) for the XO to connect to your wireless network through the Sugar UI. It is possible to connect manually by typing commands in Terminal.

a kernel bug

February 2014 identified a nasty kernel bug with a proposed solution that may be installed in future XO-1 software releases.

Problem: with a stored connection, on reboot Sugar will often not connect to it, because the network is not shown in network neighbourhood, in turn because the scan results did not include the network, in turn because the scan results were lost or corrupted, in turn because of a flaw in the kernel or wireless firmware, in turn triggered by the presence of a single mesh node.

Workaround: start Terminal, and type "sudo iwlist eth0 scan" and press enter, check back with the network neighbourhood view, and repeat the command until your access point is shown.

It may explain why many deployments turned off mesh networking in their builds.

access point not in channels 1, 6 or 11.

Is your access point working on another channel (not in 1, 6 or 11)? For some (old) builds the XO expects to find access points in one of these three channels (by the way, these are the three non interfering channels available to 802.11g). Try changing your access point to one of the three and check if you can associate your XO to it.

access point restricted to certain MAC addresses

Does your access point have a white list of MAC addresses? To learn the MAC address of your XO laptop, go to term, then run ifconfig. Make sure that if your access point is restricted to a white list of MAC addresses, make sure your laptop's MAC address is on the list.

Why can't the XO browse when connected?

Symptom: I can connect, but I cannot browse/search any pages.

Most likely, the XO has failed to receive DNS information from your internet access point. If this is the case, you would be able to access the Internet for sites named directly with IP addresses but not their common names. In other words, http://209.85.133.18/ would work but http://www.google.com/ would not.

Verify what the XO has received (from the Internet access point) for DNS information by using the Browse activity and looking at this URL:

 file://localhost/etc/resolv.conf

This page should show the IP address of the DNS server assigned by the Internet access point. If there isn't an IP address on this page, or if the IP address assigned is wrong, this would account for the behavior you're seeing.

If there is no IP address, or the address is wrong, you'll need to determine why the Internet access point is failing to supply one, but this is likely to be misconfiguration of the access point.

What common wireless symptoms do users report?

• I cannot associate to an Access Point from the mesh view. (The symptom is usually a flashing circle icon where the rim of the circle never turns white—this indicates the XO is trying to connect, but the connection fails.)

• I associate but I have no connectivity; or I cannot access the Internet from the browser in my XO.

• I cannot connect to my Access Point since it has a hidden SSID/ESSID (network name) (see: Ask OLPC a Question about the Network#Manually adding a wireless network)

• The window disappears, the Access Point's circle starts blinking and after some time, the windows is displayed again.

How to test the antenna?

The antenna can be broken by dropping or too much rotating. Sometimes it can look fine but still be broken inside. A broken antenna may stop internet, or may restrict it to work only right next to an access point. See Antenna testing for how to test the antenna.

What information is needed to help diagnose wireless problems?

If you are experiencing problems with wireless connectivity, here is a list of information that you should provide your friends and OLPC community, so they can help you in the diagnosis of the wireless problems.

• The software build on your XO. Please see this How to check the OS and firmware versions page to find your software build.

• The access point/router brand, model, version, and firmware version (ideally).

• The security configuration of your wireless home system. Most access points will be open (security disabled) by defualt. If you configured it to use cryptography (WEP, WPA, WPA2, etc) you should gather this information.

• The description of the problem.

Other useful information you should consider adding to your description:

• Do you see the wifi Access Point in the mesh view?
• Have you previously successfully connected to this Access Point from an XO?
• Can you connect to the Access Point from another non-XO laptop?
• Is the Access Point displayed as protected (a lock badge appears), or as open in the mesh view? Is it consistent to the Access Point's configuration?
• When you click on the Access Point circle does it:
  
  • start blinking and after some time stop, without connecting? (no external white circle)
  • prompt for a window with:
    • a menu for "Encryption type" only
    • a menu for "Key type" and another for "Association Type"
• In case you have a protected Access Point what happens after you type in a passphase or a key?