Wifi Troubleshooting Guide: Difference between revisions

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{{G1G1 Support FAQ}}
{{G1G1 Support FAQ}}


===Is the wifi hotspot dot visible?===
=== Is your network name visible? ===


In the [[Neighborhood View]], you should clearly see your wifi hotspot's network name. If you cannot see the network name...
After the laptop starts up, the [[Neighborhood View]] should show a circle for each network. Move the mouse over each to see the network name. If your network name is not shown, then perhaps:


* you have a hidden network;
==== hidden SSID ====


::Is your network hidden? You cannot connect to a hidden network in Sugar. You can switch to Gnome to connect, and then switch back to Sugar. Some deployment teams have added hidden network support, contact Sugar Labs.
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]].


* you hit our bug: and networks appear very slowly;
==== a kernel bug ====


::OLPC OS 13.2.0 and earlier don't show networks quickly enough, especially when there are many hidden networks or XO-1 laptops nearby. Call your deployment team to get it fixed, or see [[12757]] for details and a fix from OLPC.
February 2014 [http://lists.laptop.org/pipermail/devel/2014-February/thread.html#38128 identified] a nasty [http://lists.laptop.org/pipermail/server-devel/2014-February/007193.html kernel bug] with a [http://dev.laptop.org/ticket/12757 proposed solution] that may be installed in future XO-1 software releases.


* your operating system is too old;
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.


::Is your network on another channel other than 1, 6 or 11)? For some very old operating system releases, only these channels are scanned. Try upgrading. Try changing your network to one of these channels and check if you can connect to it.
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.


⚫
* your network is restricted to certain MAC addresses;
It may explain why many deployments turned off mesh networking in their builds.


⚫
::Does your network have a white list of MAC addresses? To learn the MAC address of your XO laptop, go to Terminal, then type {{code|ifconfig}}. If your network is restricted to a white list of MAC addresses, add your laptop to the list.
==== 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? ===
===Why can't the XO browse when connected? ===
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===What common wireless symptoms do users report?===
===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 cannot connect to a network from the network neighbourhood 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 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]])
* I cannot connect to my network because it is a hidden network. (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.
* The password window disappears, the network starts blinking and after some time, the password window is displayed again.


=== How to test the antenna? ===
=== 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.
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 of a network. See [[Antenna testing]] for how to test the antenna.


===What information is needed to help diagnose wireless problems?===
===What information is needed to help diagnose wireless problems?===
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* The access point/router brand, model, version, and firmware version (ideally).
* 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 security configuration of your wireless home system. Some access points will be open (security disabled) by default. If you configured it to be secure, you should gather this information; the type of security, and whether it works from another computer.


* The description of the problem.
* The description of the problem.
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Other useful information you should consider adding to your description:
Other useful information you should consider adding to your description:


* Do you see the wifi Access Point in the mesh view?
* Do you see the network in the mesh view?
* Have you previously successfully connected to this Access Point from an XO?
* Have you previously successfully connected to this network from an XO?
* Can you connect to the Access Point from another non-XO laptop?
* Can you connect to the network 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?
* Is the network 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:<br>
* When you click on the network circle does it:<br>
** start blinking and after some time stop, without connecting? (no external white circle)
** start blinking and after some time stop, without connecting? (no external white circle)
** prompt for a window with:
** prompt for a window with:
*** a menu for "Encryption type" only
*** a menu for "Encryption type" only
*** a menu for "Key type" and another for "Association Type"
*** 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?
* In case you have a secured network, what happens after you type in a passphase or a key?

Latest revision as of 03:46, 12 February 2014

This page is part of the XO Support FAQ.     Support Index | Print This Page
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Is your network name visible?

After the laptop starts up, the Neighborhood View should show a circle for each network. Move the mouse over each to see the network name. If your network name is not shown, then perhaps:

  • you have a hidden network;
Is your network hidden? You cannot connect to a hidden network in Sugar. You can switch to Gnome to connect, and then switch back to Sugar. Some deployment teams have added hidden network support, contact Sugar Labs.
  • you hit our bug: and networks appear very slowly;
OLPC OS 13.2.0 and earlier don't show networks quickly enough, especially when there are many hidden networks or XO-1 laptops nearby. Call your deployment team to get it fixed, or see 12757 for details and a fix from OLPC.
  • your operating system is too old;
Is your network on another channel other than 1, 6 or 11)? For some very old operating system releases, only these channels are scanned. Try upgrading. Try changing your network to one of these channels and check if you can connect to it.
  • your network is restricted to certain MAC addresses;
Does your network have a white list of MAC addresses? To learn the MAC address of your XO laptop, go to Terminal, then type ifconfig. If your network is restricted to a white list of MAC addresses, add your laptop to 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 connect to a network from the network neighbourhood 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.
  • The password window disappears, the network starts blinking and after some time, the password window 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 of a network. 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 access point/router brand, model, version, and firmware version (ideally).
  • The security configuration of your wireless home system. Some access points will be open (security disabled) by default. If you configured it to be secure, you should gather this information; the type of security, and whether it works from another computer.
  • The description of the problem.

Other useful information you should consider adding to your description:

  • Do you see the network in the mesh view?
  • Have you previously successfully connected to this network from an XO?
  • Can you connect to the network from another non-XO laptop?
  • Is the network 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 network 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 secured network, what happens after you type in a passphase or a key?
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