Take the 2-minute tour ×
Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free, no registration required.

I got a TP-LINK USB wireless module - TL-WN821N, using Ubuntu 10.04 (same problems were also seen in 10.10).

From everything I've read online, the usb adapter should work just fine, since the Atheros ar9170 driver is built into the kernel. However, when I plug it in, it is detected as a USB device, but there is no wlan associated with it, and basically - nothing happens.

Am I doing something wrong? what should I do so that the Atheros driver is associated with this device?

btw, on Windows it works fine (with the drivers).

Some logs:

$ uname -mr
2.6.32-28-generic i686

$ lsb_release -d
Description:    Ubuntu 10.04.2 LTS

$ lsusb
... (trimmed)
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 017: ID 0cf3:7015 Atheros Communications, Inc. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

$ lsmod |grep ar9
ar9170usb              51296  0 
ath                     7611  1 ar9170usb
mac80211              205402  3 ar9170usb,iwl3945,iwlcore
cfg80211              126528  5 ar9170usb,ath,iwl3945,iwlcore,mac80211
led_class               2864  4 ar9170usb,iwl3945,iwlcore,sdhci
share|improve this question
Run sudo lshw, and try to find the driver associated with the device (It comes in the last line of the output). It should also show you the chipset of the device (which need not necessarily be atheros compatible). –  apoorv020 Mar 3 '11 at 7:04
It's is Atheros, cause I see in the lsusb "Atheros Communications, Inc.". But I don't see it in lshw...not in the *-network and not in *-usb. –  user11745 Mar 3 '11 at 7:16

2 Answers 2

I got the adapter seen by the system. I’m running debian squeeze (2.6.32-5-686-bigmem). I installed the backport version of firmware-atheros as thats the one that had the firmware within it that the adapter needs. (http://packages.debian.org/squeeze-backports/firmware-atheros)

Then I downloaded the kernel headers. (Well they were already installed)

Next I had to download the compat-wireless source code and compile it myself. (This either contains the ath9k_htc source code from the Wheezy firmware-ateros package or a compatible version) Here is the website I followed to get the source and compile it http://wireless.kernel.org/en/users/Download

All this wasnt too dificult but I’m still having a few issues getting it to connect.

I will update once I’ve worked that out. If how ever your running Wheezy then take a look at this page http://wiki.debian.org/ath9k_htc

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.