LaFambe
Posts: 12
Joined: Fri Dec 13, 2013 7:21 pm

ping DUP! using wireless TL-WN725N v2 dongle

Mon Dec 16, 2013 9:00 pm

Hi there,

I am getting dups when pinging to/from my rpi model B, basic raspbian setup, 3.6.11+ #538, equipped with the TL-WN725N v2 dongle + relevant driver (8188eu-20130830.tar.gz from here). Yesterday the thing was just massive, with ping times around 200+ms and peaks well over 1s, roughly killing my wireless network. I replaced the dongle with my old wg111, all went back to normal, no dups and ping times below 20ms for over a day. I just re-booted the pi with the 725N v2 plugged and got 2 dups in 5 minutes - but none in the following hour. Yesterday I spied both sides with tcpdump -i wlan0 icmp, looked like the pi was generating 2 replies.

Anybody experienced the same issue ? Any hints on things to attempt ?

Code: Select all

bigmac:~ olaf$ jobs
[3]+  Running                 ping pi | grep DUP &
bigmac:~ olaf$ 
bigmac:~ olaf$
64 bytes from 192.168.0.5: icmp_seq=26252 ttl=64 time=16.234 ms (DUP!)
64 bytes from 192.168.0.5: icmp_seq=26313 ttl=64 time=59.361 ms (DUP!)

pi@raspberrypi ~ $ uname -a
Linux raspberrypi 3.6.11+ #538 PREEMPT Fri Aug 30 20:42:08 BST 2013 armv6l GNU/Linux
pi@raspberrypi ~ $ iwconfig wlan0
wlan0     IEEE 802.11bgn  ESSID:"joolaf"  Nickname:"<WIFI@REALTEK>"
          Mode:Managed  Frequency:2.462 GHz  Access Point: 32:BA:4D:6A:F8:9C   
          Bit Rate:150 Mb/s   Sensitivity:0/0  
          Retry:off   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=90/100  Signal level=61/100  Noise level=0/100
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

pi@raspberrypi ~ $ ifconfig wlan0
wlan0     Link encap:Ethernet  HWaddr 10:fe:ed:14:da:11  
          inet addr:192.168.0.5  Bcast:192.168.0.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:4298 errors:0 dropped:116 overruns:0 frame:0
          TX packets:4167 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:4973183 (4.7 MiB)  TX bytes:419784 (409.9 KiB)

pi@raspberrypi ~ $ uptime
 00:19:08 up 5 min,  1 user,  load average: 0.10, 0.16, 0.09

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DougieLawson
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Re: ping DUP! using wireless TL-WN725N v2 dongle

Mon Dec 16, 2013 9:26 pm

Do you have two machines on your LAN that both have 192.168.0.5?

Try arp -an and see if two unique MAC addresses have the same IP address.
You may need to run arp -an from more than one machine to narrow down the search.
Any language using left-hand whitespace for syntax is ridiculous

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LaFambe
Posts: 12
Joined: Fri Dec 13, 2013 7:21 pm

Re: ping DUP! using wireless TL-WN725N v2 dongle

Mon Dec 16, 2013 11:00 pm

I did check arp tables on all running hosts (except on the adsl box/router/dhcp server) and there are no conflicts. The dhcp server is anyway setup to statically provide well-known ip addresses (192.168.0.5 included) based on mac addresses.

LaFambe
Posts: 12
Joined: Fri Dec 13, 2013 7:21 pm

Re: ping DUP! using wireless TL-WN725N v2 dongle

Fri Jan 03, 2014 9:16 am

Upgraded kernel to 3.10.24+ #614 via rpi-update, upgraded 8188eu.ko and firmware (via http://www.raspberrypi.org/phpBB3/downl ... hp?id=5536). Did not help much.

Over a period of 8 days, I get random DUPs bursts, 6-8 times a day, with the rpi continuously playing http://mp3.live.tv-radio.com/fip/all/fiphautdebit.mp3 through xmms2 and a usb-dac, and no other user activity except for the control host pinging the rpi. Similar test using a wg111wifi dongle exhibits no dups.

I tried to overclock the rpi to 900MHz, to no avail concerning dups.
Last edited by LaFambe on Fri Jan 03, 2014 5:54 pm, edited 1 time in total.

LaFambe
Posts: 12
Joined: Fri Dec 13, 2013 7:21 pm

Re: ping DUP! using wireless TL-WN725N v2 dongle

Fri Jan 03, 2014 9:26 am

attached is my poor-man's dups-hunter.sh script, in case someone wishes to test the behaviour on their setup.
Attachments
dups-hunter.tgz
(784 Bytes) Downloaded 233 times

LaFambe
Posts: 12
Joined: Fri Dec 13, 2013 7:21 pm

Re: ping DUP! using wireless TL-WN725N v2 dongle

Tue Feb 04, 2014 10:52 pm

Upgrading with rpi-update to 3.10.28+ #634 and installing corresponding driver (8188eu-20140128.tar.gz) apparently solves the issue. Thanks MrEngman !! No more dups so far, plain stable wifi network, and very correct rtt. I still get about 2% packets drop, mostly harmless.

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