C2 and Wifi module 5 problem

[davidwkerr]

I have a number of Odroids (XU4, C1+) and just received a C2 on which I have installed Kodi and the HiFi Slield 2. It is running 16.04 Ubuntu as received from hardkernel.

Previously, I have used the WiFi module 3 but bought a Module 5 with this C2.

Everything works fine EXCEPT that the Wifi module 5 disconnects approximately every two minutes from the AP which is a reliable unit servicing a number of other devices without any problems. It is running on 5GHz, channel 36 (+38) with no other competing APs nearby. Distance from the AP makes no difference. I have a number of other 5GHz devices and have no problem with them. This is using the Network Manager and strangely, the Network Manager on the C2 cannot "see" any of the 2.4GHz APs of which there are about 10 in the vicinity. It is as if it is stuck in a 5GHz mode. But that is not my main concern.

I am using the hardkernel 240V adaptor. The problem happens with only the module 5 plugged into USB and also happens if I have bluetooth and a Logitech USB adaptor plugged in. I have tried 3 of the 4 USB ports. It makes no difference.

The dmesg says: wlan0: deauthenticated from xx:xx:xx:xx:xx:xx (Reason: 7)
Then it reauthenticates after 5 to 20seconds.

Does anyone know what "reason 7" is?

Kernel is 3.14.79-116

A module 3 works fine in the same odroid.

lsusb: Bus 001 Device 005: ID 148f:5572 Ralink Technology, Corp. RT5572 Wireless Adapter

Driver is rt2800usb.

Does anyone have any thoughts or suggestions that might lead to making this thing work reliably?

Thanks,
David

[odroid]

I can't reproduce your issue on my side with the same kernel version.

I've connected to a 2.4Ghz AP with WiFi module 5.

Code: Select all

odroid@odroid64:~$ iwconfig                                                     
eth0      no wireless extensions.                                               
                                                                                
wlan0     IEEE 802.11bgn  ESSID:"Charles_2.4G"  Nickname:"<WIFI@REALTEK>"       
          Mode:Managed  Frequency:2.427 GHz  Access Point: 88:36:6C:33:8A:C4    
          Bit Rate:300 Mb/s   Sensitivity:0/0                                   
          Retry:off   RTS thr:off   Fragment thr:off                            
          Power Management:off                                                  
          Link Quality=100/100  Signal level=-45 dBm  Noise level=0 dBm         
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0              
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0              
                                                                                
lo        no wireless extensions.

Driver is 8812au.

I could run a ping test over 10 minutes.

Code: Select all

odroid@odroid64:~$ ping 8.8.8.8                                                 
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.                                    
64 bytes from 8.8.8.8: icmp_seq=1 ttl=40 time=56.2 ms                           
64 bytes from 8.8.8.8: icmp_seq=2 ttl=40 time=53.8 ms                           
64 bytes from 8.8.8.8: icmp_seq=3 ttl=40 time=55.2 ms                           
64 bytes from 8.8.8.8: icmp_seq=4 ttl=40 time=55.8 ms                           
64 bytes from 8.8.8.8: icmp_seq=5 ttl=40 time=56.8 ms                           
64 bytes from 8.8.8.8: icmp_seq=6 ttl=40 time=54.3 ms                           
64 bytes from 8.8.8.8: icmp_seq=7 ttl=40 time=97.3 ms                           
64 bytes from 8.8.8.8: icmp_seq=8 ttl=40 time=53.7 ms                           
64 bytes from 8.8.8.8: icmp_seq=9 ttl=40 time=53.5 ms                           
64 bytes from 8.8.8.8: icmp_seq=10 ttl=40 time=53.5 ms                          
64 bytes from 8.8.8.8: icmp_seq=11 ttl=40 time=53.7 ms                          
64 bytes from 8.8.8.8: icmp_seq=12 ttl=40 time=53.7 ms                          
64 bytes from 8.8.8.8: icmp_seq=13 ttl=40 time=54.2 ms                          
64 bytes from 8.8.8.8: icmp_seq=14 ttl=40 time=52.9 ms                          
64 bytes from 8.8.8.8: icmp_seq=15 ttl=40 time=54.3 ms                          
64 bytes from 8.8.8.8: icmp_seq=16 ttl=40 time=60.0 ms

5Ghz connection also has no issue.

Should I do another way to reproduce your issue?
Did you update system with "sudo apt update && sudo apt upgrade && sudo apt dist-upgrade"?

[davidwkerr]

Hi odroid,
Many thanks for the quick response.
Yes, I had updated everything.
The problem is now solved. The issues were:

a. Power management was ON by default with Wlan0 and it really does not work very well. So, I disabled it permanently and that solved the deauthentication issue (which even happened if there was a Ping running or music streaming- so it should not have gone to sleep).

b. There was a further problem with lots of missed packets. What I found was that the router (DD-WRT WNDR4000) had the Module-5 represented as HT20 whereas the Module-5 thought it was HT40! Other devices at 5GHz were correct. So probably everything going down the second frequency were being lost at the router. So, I upgraded the DD-WRT version and that fixed this other problem. Now both ends of the connection show HT40 and everything is working properly now.

Best Regards and Happy Christmas to all at Hardkernel,

David

[odroid]

Good to hear you solved the issue.
Happy Christmas to you too.

[rushcoil]

Hi David, how did you managed to disable the power management?