Solved: Raspbian with Edimax EW-7811UN WiFi Adapter and 802.1X authentication or WPA shared key authentication

Solved: Raspbian with Edimax EW-7811UN WiFi Adapter and 802.1X authenticationRecently I wanted to set up Wireless (Wi Fi) Ethernet 802.1X authentication on a Raspberry Pi with Raspbian “wheezy” 3.6 (version 3.6.11 actually) and the Edimax EW 7811UN WiFi Adapter.

Solved: Raspbian with Edimax EW-7811UN WiFi Adapter and 802.1X authenticationI had read a lot of posts about having trouble with the Edimax adapter – and how you would need to replace the driver file cfg80211.ko and / or rebuild one from the source code. This simply wasn’t true for me – the device worked very well right out of the box – with a few small configuration changes which I will share with you.

Here is my setup:

  • Raspberry Pi was a “Pi Model B” with the 512MB of memory
  • Downloaded Raspbian wheezy from the downloads site – version was `2013-05-25-wheezy-raspbian.zip1
  • Created a SD card with the image
  • EW-7811UN WiFi Adapter

Notes:

  • If you boot up the Pi and then plug in the EW-7811UN WiFi Adapter directly to the Pi, it will likely crash / reboot the Pi. This is not a problem with either device, but the EW-7811UN WiFi Adapter requires a lot of power and so it underloads the Raspberry Pi’s circuits and causes this behavior.
  • If you have a powered USB hub (in my case my monitor) and plug / unplug the EW-7811UN WiFi Adapter then you will not cause the system to crash / reboot
  • I did my initial bootup of the Pi without the EW-7811UN WiFi Adapter plugged in
  • I did not select any special options on the first boot – I just went down and hit the “continue” button
  • After rebooting, I logged in as pi and the command propt started but no GUI (this is expected behavior) and the EW-7811UN WiFi Adapter was still not plugged in
  • Next I plugged in the EW-7811UN WiFi Adapter into the monitor (powered usb hub) and the ran lsusb and iwconfig which both showed the EW-7811UN WiFi Adapter available. You can also use lsmod to get information on the chipset of your devices.
  • The EW-7811UN WiFi Adapter should show up as wlan0 – the third of three devices (wired, loopback, and wifi)

There are some options for the network configuration in this file, but you should not need to edit this file:

/etc/network/interfaces

The final line of that file, however, should be something like this (should already be existing):

wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf

That of course points to a file that you will need to configure:

/etc/wpa_supplicant/wpa_supplicant.conf

If you don’t know how to do that, use a command to edit using either emacs or vi and you will need to preface this with sudo:

sudo vi /etc/wpa_supplicant/wpa_supplicant.conf

If you are using WPA-PSK (not 802.1X) you can add something like this to the bottom of that file (don’t delete what is already there – just APPEND it):

network={
ssid="_SSID_"
proto=RSN
key_mgmt=WPA-PSK
pairwise=CCMP TKIP
group=CCMP TKIP
psk="_WPA_SHARED_KEY_"
}

Replace _SSID_ and _WPA_SHARED_KEY_ with the correct corresponding values.

Now for the good stuff – industrial 802.1X or 802.1X LEAP authentication – yay! Instead of appending that last block, use something like this:

network={
ssid="_SSID_"
scan_ssid=1
key_mgmt=WPA-EAP
eap=PEAP
pairwise=CCMP TKIP
group=CCMP TKIP
# authentification info
identity="_USERNAME_"
password="_PASSWORD_"
phase1="peaplabel=0"
phase1="auth=MSCHAPV2"
}

Again, be sure to replace _SSID_, _USERNAME_, and _PASSWORD_ with the correct values.

Now save the file, and reboot your pi and then run ifconfig and the wlan0 should now have a real IP address and be connected to the network! Yay!

More notes:

  • When I rebooted the first time this worked – but then I unplugged the ethernet cable, and although the wireless network was connected, the pi was still defaulting to the wired connection eth0 and so I had to reboot again after unplugging the wired connection – but upon reboot the pi was functioning with wireless with NO PROBLEMS with the Edimax EW-7811UN WiFi Adapter – woot woot!
  • Update: I left the pi turned off overnight and when I turned it on again it didn’t connect to the wireless. Running lsusb showed that the adapter was not available. I unplugged the adapter, rebooted, then inserted the adapter after it was booted up. The adapter showed up. After rebooting once again it connected to the WiFi automatically. There are probably some commands to facilitate connecting automatically after a period of the pi being off but I haven’t discovered yet.

Related Posts:

  • No Related Posts
This entry was posted in Tech Tips and tagged , , . Bookmark the permalink.

One Response to Solved: Raspbian with Edimax EW-7811UN WiFi Adapter and 802.1X authentication or WPA shared key authentication

  1. Christopher Stevens says:

    Thanks for this! I just obtained the same Edimax EW-7811Un adapter and can confirm that everything worked like a dream right away (2 years after your post it appears!).

    The challenge I’m having right now is getting it to scan or connect to a 5GHz wireless network, leaving the clutter and overlapping frequencies of a 2.4GHz network. So far I’m finding comments about that happening on the router side, not the client side. Even after splitting up the connections and labeling it “5GHz” on the router, I can’t seem to connect or scan for it on the Pi.

    Let me know if you’ve had luck with this or tried it out. :D

    Thanks again,

    Chris

Leave a Reply

Your email address will not be published. Required fields are marked *