Raspberry pi frequently disconnecting and reconnecting from wifi network

Question

My raspberry pi 2 (running Ubuntu 14.04) with SIIG wireless mini adapter is unable to maintain a connection with the access point. It does not seem to be signal strength related, as it behaves well while connected.

The setup has the raspberry pi powered from a powered USB 3 hub, with the wifi adapter also connected to the hub, and the raspberry pi also connected to the hub as master.

I have r8188 module loaded, with power saving disabled:

cat /etc/modprobe.d/r8188eu.conf

options r8188eu rtw_power_mgnt=0 rtw_enusbss=0

iwconfig wlan0 shows:

wlan0     IEEE 802.11bgn  ESSID:"xxxxxxxx"  Nickname:"<WIFI@REALTEK>"
      Mode:Managed  Frequency:2.437 GHz  Access Point: 00:11:22:33:44:55   
      Bit Rate:72.2 Mb/s   Sensitivity:0/0  
      Retry:off   RTS thr:off   Fragment thr:off
      Encryption key:****-****-****-****-****-****-****-****   Security mode:open
      Power Management:off
      Link Quality:0/100  Signal level:40/100  Noise level:0
      Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
      Tx excessive retries:0  Invalid misc:0   Missed beacon:0

But the signal level reported changes from 0 to 40. On the router side it indicates 4 or 5 bars to this device.

From /etc/network/interfaces:

auto wlan0
iface wlan0 inet dhcp
wpa-conf /etc/wpa_supplicant.conf
wireless-power off

Pinging from other machine on wireless network:

Request timeout for icmp_seq 2327
Request timeout for icmp_seq 2328
64 bytes from 192.168.2.199: icmp_seq=2329 ttl=64 time=4.445 ms
....
64 bytes from 192.168.2.199: icmp_seq=2341 ttl=64 time=1.969 ms
Request timeout for icmp_seq 2342
Request timeout for icmp_seq 2343

The number of successful pings is 12-15, with a similar number of requests timed out.

At boot time, this is listed in dmesg:

[    4.536377] r8188eu: module is from the staging directory, the quality is unknown, you have been warned.
[    4.666079] Chip Version Info: CHIP_8188E_Normal_Chip_TSMC_UNKNOWN_CUT(10)_1T1R_RomVer(0)
[    4.872514] usbcore: registered new interface driver r8188eu

In dmesg output, this is repeated:

[ 1604.256629] R8188EU: ERROR linked_status_chk(wlan0) disconnect or roaming
[ 1606.205210] R8188EU: ERROR assoc success
[ 1630.304910] R8188EU: ERROR linked_status_chk(wlan0) disconnect or roaming
[ 1632.523159] R8188EU: ERROR assoc success

Looking in /var/log/syslog:

Sep 23 20:15:20 piweather2 kernel: [ 1790.628050] R8188EU: ERROR linked_status_chk(wlan0) disconnect or roaming
Sep 23 20:15:22 piweather2 kernel: [ 1792.578095] R8188EU: ERROR assoc success
Sep 23 20:15:22 piweather2 wpa_supplicant[498]: wlan0: Associated with 00:11:22:33:44:55
Sep 23 20:15:22 piweather2 wpa_supplicant[498]: wlan0: WPA: Key negotiation completed with 00:11:22:33:44:55 [PTK=CCMP GTK=CCMP]
Sep 23 20:15:22 piweather2 wpa_supplicant[498]: wlan0: CTRL-EVENT-CONNECTED - Connection to 00:11:22:33:44:55 completed [id=0 id_str=]
Sep 23 20:15:44 piweather2 kernel: [ 1814.672934] R8188EU: ERROR linked_status_chk(wlan0) disconnect or roaming
Sep 23 20:15:46 piweather2 kernel: [ 1816.641622] R8188EU: ERROR assoc success
Sep 23 20:15:46 piweather2 wpa_supplicant[498]: wlan0: WPA: EAPOL-Key Replay Counter did not increase - dropping packet
Sep 23 20:15:46 piweather2 wpa_supplicant[498]: wlan0: Associated with 00:11:22:33:44:55
Sep 23 20:15:47 piweather2 wpa_supplicant[498]: wlan0: WPA: Key negotiation completed with 00:11:22:33:44:55 [PTK=CCMP GTK=CCMP]
Sep 23 20:15:47 piweather2 wpa_supplicant[498]: wlan0: CTRL-EVENT-CONNECTED - Connection to 00:11:22:33:44:55 completed [id=0 id_str=]

Not sure what more I can try, so looking for advice

Thanks

score 3 · Answer 1 · answered Nov 11 '15 at 20:21

Can be a power issue! (Although may not be because you are using the hub)

I had the same issue, and usually it is due to power. So check that the power supply is at least 1 amp (Prefer 2), and if it is and you have lots of devices connected to the USB/GPIO that can also be the case.

For an example: My raspberry pi runs on 1.8 amp and I had a keyboard, WiFi dongle, and a wireless mouse adapter connected. The WiFi would not be accessible due to the lack of power. So I connected a 2.1 amp supply and it worked.

score 0 · Answer 2 · answered Oct 16 '15 at 15:42

There are many reasons for Wifi disconnects

Not just power saving mode

1. Network interference

This is what happened to me. It is possible for another device on your network to accidentally have the same IP address as your RPi. This is easily fixed by reserving an IP address on your router. Since ever router is different you will have to do a few google searches for how to do this. Just search "reserved IP address" and the make and model of your router.

2. Forced Sleep

Some Wifi cards have a forced sleep with the RPi. This is an even simpler fix. Just right a program that pings your router every minute or so, and keep it running in the background.

3. Not Enough Power

This shouldn't be a problem considering you have it plugged into a USB hub, but it's not going to hurt to check. Make sure your USB hub is delivering ~5.0-5.5v and at least ~1A. If you have a multimeter this will be easy.

Raspberry pi frequently disconnecting and reconnecting from wifi network

2 Answers2

There are many reasons for Wifi disconnects