D-Link DWA-131 Wifi dongle (r8712u driver) issue

Help and Support
1

Hello, this is my first post.
First of all, I wish to thank you all developers for their great work.

I’ve been having issue with my wifi usb dongle (D-Link DWA-131 rev.A) using r8712u driver on my raspberry pi2 running latest osmc version (2015.09-2).

Connection is correctly established when osmc is loaded, I can access Kodi http server, ssh and all the active services (transmission, etc). After a while (minutes, sometimes hours) connection drops end the blue led on wifi dongle starts blinking.
Unplugging and plugging wifi dongle doesn’t resolve the issue, connection is restablished only after a complete reboot.

What can I do to help you detecting the issue? What type of log file is needed (journal log and or other log files)?

Thank you

Luke

2

The system journal is the main one needed for troubleshooting a wifi connection although providing all logs wouldn’t hurt.

After the problem occurs you could then temporarily connect Ethernet to upload the logs or choose to save the logs on the SD card.

3

My system journal log:
http://paste.osmc.io/adibinowuy

Rebooted my system yesterday in the evening, this morning found wifi dropped.
If you need something else, please tell me.
Thank you

4

You have a lot of errors like this:

Oct 07 23:48:59 osmc wpa_supplicant[320]: wlan0: Michael MIC failure detected
Oct 07 23:48:59 osmc wpa_supplicant[320]: wlan0: WPA: Sending EAPOL-Key Request (error=1 pairwise=0 ptk_set=1 len=99)
Oct 07 23:48:59 osmc wpa_supplicant[320]: wlan0: WPA: Key negotiation completed with 00:14:6c:aa:a7:08 [PTK=CCMP GTK=TKIP]
Oct 07 23:48:59 osmc connmand[271]: Probably roaming right now! Staying connected...
Oct 07 23:49:01 osmc wpa_supplicant[320]: wlan0: Michael MIC failure detected
Oct 07 23:49:01 osmc wpa_supplicant[320]: wlan0: WPA: Sending EAPOL-Key Request (error=1 pairwise=0 ptk_set=1 len=99)
Oct 07 23:49:01 osmc wpa_supplicant[320]: wlan0: TKIP countermeasures started
Oct 07 23:49:01 osmc connmand[271]: wlan0 {RX} 1243324 packets 1017192013 bytes
Oct 07 23:49:01 osmc connmand[271]: wlan0 {TX} 2538799 packets 2855484772 bytes

From my understanding this is caused if your AP goes into TKIP countermeasure mode to try to thwart a key recovery attack - in other words there could be a malicious device nearby that is sending probes to your AP that is triggering it to protect itself - in the process all clients will drop for about a minute then try to reconnect after rekeying. There is a bit of reading about TKIP countermeasures here:

The best solution would be for you to disable WPA with TKIP encryption on your base station and use only WPA2 with AES encryption - the vast majority of devices these days support WPA2 with AES encryption, which is not vulnerable to this type of attack and the resulting connection loss that it can cause.

WPA using TKIP is no longer considered to be fully secure so should be turned off if all your devices support WPA2.

5

Thank you @DBMandrake
I noticed that connection drops at the first occurrence of “Michael MIC failure detected”, then all the attempts to recover connection fail.

System log on my AP doesn’t show errors.

I think that r8712u driver crash after some time and it could not recover itself without a complete reboot. I remember that with older osmc releases (rc4 and maybe first stable releases) I didn’t have this issue. Is it possible that something has been changed on r8712u driver and/or wpa_supplicant?

Sadly my AP (an old Netgear DG834PN) doesn’t support WPA2 without TKIP, so I can’t disable it.

Hope to solve this annoying issue. Is there some action I can do to help resolving this problem?

Thank you again

6

Ok, I’m here again.
I ask you for some help.

I changed my old router with a new Fritz!Box 3470.
My Raspberry Pi2 has the same Wi-fi USB Adapter (Dlink DWA-131 rev A) and it is updated to OSMC version 2015.12-3.

After some time Raspberry got disconnected, with adapter blue-light blinking with regular rate.

This is my complete log:
http://paste.osmc.io/osokaduval.vhdl

I think now problem is different, I see these lines on system journal
Jan 07 20:40:41 osmc mediacenter[485]: Pulse =========================================== Jan 07 20:40:41 osmc mediacenter[485]: Error in function pulse Jan 07 20:40:41 osmc mediacenter[485]: Traceback (most recent call last): Jan 07 20:40:41 osmc mediacenter[485]: File "/usr/share/kodi/addons/script.module.osmcsetting.updates/resources/lib/apt_cache_action.py", line 491, in pulse Jan 07 20:40:41 osmc mediacenter[485]: msg = self.fetching Jan 07 20:40:41 osmc mediacenter[485]: AttributeError: 'Download_Progress' object has no attribute 'fetching'

I don’t know if this is THE error or only a consequence of the error.
Do you see something else wrong in my logs?

Thank you in advance,
compliments for your great work

Luke

7

The error you have highlighted is simply the My OSMC updater being unable to check for updates due to the network connection not working, so is a side effect not a cause.

There is actually nothing in your logs to indicate that your wifi connection has dropped. Are you sure it’s an issue with the wifi connection ?

Are you still able to ping the Pi ? Does your router still show the Pi as a connected wifi device ?

Is the Pi a long way from the router ?

8

Thank you @DBMandrake,

Pi was without wi-fi connection (no ping and on router there weren’t any connected device).
On router log I saw “Deregistering wireless LAN device: Device not responding. MAC address: […].”
Pi is three meter from my Fritz!Box, connection is established at 70Mbps.

Do you think is a wi-fi signal strength issue?