[SOLVED] TL-WN722N wireless dongle setup

gvaught · 06-19-2016, 08:56 AM

I'm placing this out here so I can find my process and make it available for anyone else who finds themselves in this situation. I've worked through this a couple of times, but am not certain that I have it down to a science. I will update this post or thread as is appropriate.

I am running Debian 8.4 (Jessie) on a box that previously ran Ubuntu (15, I think) and worked my wireless dongle with no issues. So, when I reloaded the system with Debian, I expected some but not much transitional pain. I was not let down.

First of all, I need to list my sources of information. I did find the man page for wpa_supplicant online and printed it out. I did not end up using it, but I did have it. I also printed out and used the following two web pages (in order):

http://elinux.org/RPi_Peripherals
https://blog.nelhage.com/2008/08/usi...-debianubuntu/

I also read a number of other sites, but these two had the information which helped me get where I wanted to be.

First, I modified my /etc/network/interfaces file to include the interface for the wireless dongle

Code:

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

# The wireless interface
auto wlan0
iface wlan0 inet dhcp
wpa-driver wext
wpa-conf /etc/wpa.conf

After that, I ran iwconfig to verify the interface was working. I got this result.

Code:

eth0      no wireless extensions.

wlan0     IEEE 802.11bgn  ESSID:"MY_SSID"  
          Mode:Managed  Frequency:2.462 GHz  Access Point: 00:00:00:00:00:00   
          Bit Rate=54 Mb/s   Tx-Power=20 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=40/70  Signal level=-70 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:889   Missed beacon:0

lo        no wireless extensions.

Then, I ran iwlist wlan0 scan and found my network in the list (below) which provided me with information to make the /etc/wpa.conf file in the next step.

Code:

wlan0     Scan completed :
          Cell 01 - Address: 00:00:00:00:00
                    Channel:11
                    Frequency:2.462 GHz (Channel 11)
                    Quality=39/70  Signal level=-71 dBm  
                    Encryption key:on
                    ESSID:"MY_SSID"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s
                              24 Mb/s; 36 Mb/s; 54 Mb/s
                    Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 48 Mb/s
                    Mode:Master
                    Extra:tsf=0000000c72ce4a7f
                    Extra: Last beacon: 112ms ago
                    IE: Unknown: 000A696E74656C6C6974656B
                    IE: Unknown: 010882848B962430486C
                    IE: Unknown: 03010B
                    IE: Unknown: 2A0106
                    IE: Unknown: 2F0106
                    IE: IEEE 802.11i/WPA2 Version 1
                        Group Cipher : CCMP
                        Pairwise Ciphers (1) : CCMP
                        Authentication Suites (1) : PSK
                    IE: Unknown: 32040C121860
                    IE: Unknown: 2D1AEC181BFFFF000000000000000000000000000000000000000000
                    IE: Unknown: 3D160B001700000000000000000000000000000000000000
                    IE: Unknown: DD09001018020510080000
                    IE: WPA Version 1
                        Group Cipher : CCMP
                        Pairwise Ciphers (1) : CCMP
                        Authentication Suites (1) : PSK

Next, I created /etc/wpa.conf. I believe the name and location of this file is not critical, as another posting showed it as /etc/wpa_supplicant/wpa_supplicant.conf, YMMV. For completeness, I'll list their example entries and my final entry.

Code:

network={
ssid="NETWORK-SSID"
proto=RSN
key_mgmt=WPA-PSK
pairwise=CCMP TKIP
group=CCMP TKIP
psk="YOUR-WLAN-PASSWORD"
}

network={
    ssid="MIT"
    key_mgmt=NONE
}

network={
    ssid="langtonlabs"
    key_mgmt=NONE
    wep_key0=deadbeef
}

network={
    ssid="wireless-is-a-lie"
    psk="passw0rd"
}

# mine (obfuscated)
ssid="MY_SSID"
key_mgmt=WPA-PSK
pairwise=CCMP
group=CCMP
psk="myNetworkPrivatePassword"
}

I believe that this is the time to run ifup wlan0 to try to start the interface working.

Running ifconfig nets this for wlan0

Code:

wlan0     Link encap:Ethernet  HWaddr 00:00:00:00:00:00  
          inet addr:192.168.2.0  Bcast:192.168.2.255  Mask:255.255.255.0
          inet6 addr: fe80::fad1:11ff:fe19:cfe5/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:16785 errors:0 dropped:0 overruns:0 frame:0
          TX packets:14527 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:10846791 (10.3 MiB)  TX bytes:2321303 (2.2 MiB)

I did run route add default gw 192.168.2.254 wlan0, as recommended by the RaspberryPI blog entry.

One thing that I repeatedly encountered and had to deal with is the Network Settings and Network Connections utilities from the System Tray (which indicated "No Connections") blocking my access.

Network Settings has two toggle switches, one for Airplane Mode and one for Wireless. It's frustrating because it seems to always default to Airplane Mode = ON. Turning Airplane Mode to OFF (on my system) forces Wireless to switch OFF. So then you have to turn the Wireless ON. And all this time, it shows my network as "Out of range", while I write this post even. And you MAY need to tweak the configuration in Network Connections for your wireless connection. But if you can get it running without doing so, I'd leave it alone.