Manual Wireless Association

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Revision as of 04:37, 4 January 2008 by 24.19.33.37 (talk)
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Testing Wireless Connectivity

It's sometimes useful to test out manual connections to access points to help us debug the driver and wireless networking software. First test with plain 'iwconfig' tools, then with 'wpa_supplicant'. WPA and WPA2 are not currently supported, but will be in the future.

Step-by-Step with iwconfig

  • Switch to a virtual terminal by pressing Ctl+Alt+F1
  • Log in as user 'root' with no password
  • Stop NetworkManager and network scripts
service NetworkManager stop
service network stop
  • Use iwconfig to connect, replacing the 'essid' and key as necessary
iwconfig eth0 essid "my-ssid"

or for WEP:

iwconfig eth0 essid "my-ssid" key aaffbbcc667788112233449900
  • Wait a second or two, then do the following and see if the "Access Point:" and "ESSID" are set to valid values
iwconfig eth0
eth0      IEEE 802.11b  ESSID:"mmy-ssid"  
          Mode:Managed  Frequency:2.437 GHz  Access Point: 00:20:44:5a:b1:a4   
          Bit Rate:11 Mb/s   Tx-Power=20 dBm   Sensitivity=8/0  
          Retry limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=85/100  Signal level=-45 dBm  Noise level=-82 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:7
  • Wait another 10 seconds or so, and run 'iwconfig' again to ensure the connection is still active
  • Try to acquire a DHCP address
/sbin/dhclient -1 eth0
  • If the "Access Point:" value is still a valid MAC address (ie, it is _not_ all 0s), the connection is still alive
  • Switch back to the GUI by pressing Ctl+Alt+F3

Step-by-step with wpa_supplicant

  • Switch to a virtual terminal by pressing Ctl+Alt+F1
  • Log in as user 'root' with no password
  • Stop NetworkManager and network scripts
service NetworkManager stop
service network stop
  • Create a wpa_supplicant config file for your network in /etc/wpa_supplicant.conf. It should look something like this:
cat <<EOF > /etc/wpa_supplicant.conf
ctrl_interface_group=0
ctrl_interface=/var/run/wpa_supplicant
eapol_version=1
ap_scan=1
fast_reauth=1
network={
        ssid="my-ssid"
        key_mgmt=NONE
        auth_alg=OPEN
}
<press Ctrl+D here>
  • Run wpa_supplicant like this:
/usr/sbin/wpa_supplicant -ddd -ieth0 -c/etc/wpa_supplicant.conf -Dwext -o local0
  • You should see lines like:
wpa_supplicant[1710]: State: ASSOCIATING -> ASSOCIATED
wpa_supplicant[1710]: Associated to a new BSS: BSSID=00:cc:aa:34:56:12
  • In any case, please copy /var/log/messages and attach it to a bug report
cd /root
cp /var/log/messages wpa_supplicant-log.txt
bzip2 wpa_supplicant-log.txt

Attach the file /root/wpa_supplicant-log.txt.bz2 to the bug.