Wifi won't auto reconnect

jptaranto · October 10, 2019, 9:49am

I’ve attempted to troubleshoot this one by myself for some time but I haven’t turned up anything.

My wifi drops out routinely as the Pi is near a microwave - I’ve tried changing bands and what not, but it seems the drop outs are something I need to deal with. This - until now - hasn’t been a problem as the dietpi-wifi-monitor script always reconnected without issue.

After updating my Pi to the latest version of DietPi, the wifi auto reconnect script has stopped working and I can’t figure out why.

I’m using a Edimax USB adapter as so:

dietpi@KitchenPi:~$ lsusb
Bus 001 Device 004: ID 7392:7811 Edimax Technology Co., Ltd EW-7811Un 802.11n Wireless Adapter [Realtek RTL8188CUS]
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp. SMC9514 Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

The script is running fine:

dietpi@KitchenPi:~$ service dietpi-wifi-monitor status
● dietpi-wifi-monitor.service - DietPi-WiFi-Monitor
   Loaded: loaded (/etc/systemd/system/dietpi-wifi-monitor.service; enabled; vendor preset: enabled)
   Active: active (running) since Thu 2019-10-10 20:05:49 AEDT; 32min ago
  Process: 764 ExecStartPre=/bin/dash -c [ -e /sys/class/net/wlan$(sed -n 2p /DietPi/dietpi/.network) ] (code=exited, status=0/SUCCESS)
  Process: 751 ExecStartPre=/DietPi/dietpi/func/obtain_network_details (code=exited, status=0/SUCCESS)
 Main PID: 769 (dietpi-wifi-mon)
    Tasks: 2 (limit: 4915)
   CGroup: /system.slice/dietpi-wifi-monitor.service
           ├─ 769 /bin/bash /var/lib/dietpi/services/dietpi-wifi-monitor.sh
           └─2351 sleep 10

Oct 10 20:05:49 KitchenPi systemd[1]: Starting DietPi-WiFi-Monitor...
Oct 10 20:05:49 KitchenPi systemd[1]: Started DietPi-WiFi-Monitor.
Oct 10 20:05:49 KitchenPi dietpi-wifi-monitor.sh[769]: Checking connnection for: wlan0 via ping to default gateway every 10 seconds

And the connection works fine when the Pi first boots:

dietpi@KitchenPi:~$ iwconfig
eth0      no wireless extensions.

lo        no wireless extensions.

wlan0     IEEE 802.11bgn  ESSID:"Black Cockatoo"  Nickname:"<WIFI@REALTEK>"
          Mode:Managed  Frequency:2.437 GHz  Access Point: F0:9F:C2:FD:8B:24   
          Bit Rate:72.2 Mb/s   Sensitivity:0/0  
          Retry:off   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=100/100  Signal level=82/100  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

I’ve enabled logging and once the connection drops there are endless lines related to it trying to reconnect:

wpa_supplicant[6518]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2437 MHz)
Oct 10 01:25:26 KitchenPi wpa_supplicant[6518]: wlan0: Association request to the driver failed
Oct 10 01:25:27 KitchenPi dhclient[6547]: DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 5
Oct 10 01:25:32 KitchenPi dietpi-wifi-monitor.sh[775]: Detected connection loss: wlan0. Reconnecting...
Oct 10 01:25:32 KitchenPi dhclient[6613]: Killed old client process
Oct 10 01:25:32 KitchenPi dietpi-wifi-monitor.sh[775]: Killed old client process
Oct 10 01:25:33 KitchenPi dhclient[6613]: Internet Systems Consortium DHCP Client 4.3.5
Oct 10 01:25:33 KitchenPi dietpi-wifi-monitor.sh[775]: Internet Systems Consortium DHCP Client 4.3.5
Oct 10 01:25:33 KitchenPi dietpi-wifi-monitor.sh[775]: Copyright 2004-2016 Internet Systems Consortium.
Oct 10 01:25:33 KitchenPi dietpi-wifi-monitor.sh[775]: All rights reserved.
Oct 10 01:25:33 KitchenPi dietpi-wifi-monitor.sh[775]: For info, please visit https://www.isc.org/software/dhcp/
Oct 10 01:25:33 KitchenPi dhclient[6613]: Copyright 2004-2016 Internet Systems Consortium.
Oct 10 01:25:33 KitchenPi dhclient[6613]: All rights reserved.
Oct 10 01:25:33 KitchenPi dhclient[6613]: For info, please visit https://www.isc.org/software/dhcp/
Oct 10 01:25:33 KitchenPi dhclient[6613]: 
Oct 10 01:25:33 KitchenPi dhclient[6613]: Listening on LPF/wlan0/74:da:38:ea:05:03
Oct 10 01:25:33 KitchenPi dhclient[6613]: Sending on   LPF/wlan0/74:da:38:ea:05:03
Oct 10 01:25:33 KitchenPi dietpi-wifi-monitor.sh[775]: Listening on LPF/wlan0/74:da:38:ea:05:03
Oct 10 01:25:33 KitchenPi dietpi-wifi-monitor.sh[775]: Sending on   LPF/wlan0/74:da:38:ea:05:03
Oct 10 01:25:33 KitchenPi dietpi-wifi-monitor.sh[775]: Sending on   Socket/fallback
Oct 10 01:25:33 KitchenPi dhclient[6613]: Sending on   Socket/fallback
Oct 10 01:25:33 KitchenPi dhclient[6613]: DHCPRELEASE on wlan0 to 192.168.1.1 port 67
Oct 10 01:25:33 KitchenPi dhclient[6613]: send_packet: Network is unreachable
Oct 10 01:25:33 KitchenPi dietpi-wifi-monitor.sh[775]: DHCPRELEASE on wlan0 to 192.168.1.1 port 67
Oct 10 01:25:33 KitchenPi dietpi-wifi-monitor.sh[775]: send_packet: Network is unreachable
Oct 10 01:25:33 KitchenPi dietpi-wifi-monitor.sh[775]: send_packet: please consult README file regarding broadcast address.
Oct 10 01:25:33 KitchenPi dietpi-wifi-monitor.sh[775]: dhclient.c:2733: Failed to send 300 byte long packet over fallback interface.
Oct 10 01:25:33 KitchenPi dhclient[6613]: send_packet: please consult README file regarding broadcast address.
Oct 10 01:25:33 KitchenPi dhclient[6613]: dhclient.c:2733: Failed to send 300 byte long packet over fallback interface.
Oct 10 01:25:34 KitchenPi wpa_supplicant[6518]: nl80211: deinit ifname=wlan0 disabled_11b_rates=0
Oct 10 01:25:34 KitchenPi wpa_supplicant[6518]: wlan0: CTRL-EVENT-TERMINATING
Oct 10 01:25:35 KitchenPi wpa_supplicant[6654]: Successfully initialized wpa_supplicant
Oct 10 01:25:35 KitchenPi kernel: [380699.855570] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
Oct 10 01:25:35 KitchenPi dhclient[6659]: Internet Systems Consortium DHCP Client 4.3.5
Oct 10 01:25:35 KitchenPi dietpi-wifi-monitor.sh[775]: Internet Systems Consortium DHCP Client 4.3.5
Oct 10 01:25:35 KitchenPi dhclient[6659]: Copyright 2004-2016 Internet Systems Consortium.
Oct 10 01:25:35 KitchenPi dietpi-wifi-monitor.sh[775]: Copyright 2004-2016 Internet Systems Consortium.
Oct 10 01:25:35 KitchenPi dhclient[6659]: All rights reserved.
Oct 10 01:25:35 KitchenPi dietpi-wifi-monitor.sh[775]: All rights reserved.
Oct 10 01:25:35 KitchenPi dhclient[6659]: For info, please visit https://www.isc.org/software/dhcp/
Oct 10 01:25:35 KitchenPi dietpi-wifi-monitor.sh[775]: For info, please visit https://www.isc.org/software/dhcp/
Oct 10 01:25:35 KitchenPi dhclient[6659]: 
Oct 10 01:25:35 KitchenPi dhclient[6659]: Listening on LPF/wlan0/74:da:38:ea:05:03
Oct 10 01:25:35 KitchenPi dietpi-wifi-monitor.sh[775]: Listening on LPF/wlan0/74:da:38:ea:05:03
Oct 10 01:25:35 KitchenPi dhclient[6659]: Sending on   LPF/wlan0/74:da:38:ea:05:03
Oct 10 01:25:35 KitchenPi dietpi-wifi-monitor.sh[775]: Sending on   LPF/wlan0/74:da:38:ea:05:03
Oct 10 01:25:35 KitchenPi dhclient[6659]: Sending on   Socket/fallback
Oct 10 01:25:35 KitchenPi dietpi-wifi-monitor.sh[775]: Sending on   Socket/fallback
Oct 10 01:25:35 KitchenPi dhclient[6659]: DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 5
Oct 10 01:25:35 KitchenPi dietpi-wifi-monitor.sh[775]: DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 5
Oct 10 01:25:36 KitchenPi wpa_supplicant[6655]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2437 MHz)
Oct 10 01:25:36 KitchenPi wpa_supplicant[6655]: wlan0: Association request to the driver failed
Oct 10 01:25:38 KitchenPi wpa_supplicant[6655]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2437 MHz)
Oct 10 01:25:38 KitchenPi wpa_supplicant[6655]: wlan0: Association request to the driver failed
Oct 10 01:25:40 KitchenPi wpa_supplicant[6655]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2437 MHz)
Oct 10 01:25:40 KitchenPi wpa_supplicant[6655]: wlan0: Association request to the driver failed
Oct 10 01:25:40 KitchenPi dhclient[6659]: DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 6
Oct 10 01:25:40 KitchenPi dietpi-wifi-monitor.sh[775]: DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 6
Oct 10 01:25:42 KitchenPi wpa_supplicant[6655]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2437 MHz)
Oct 10 01:25:42 KitchenPi wpa_supplicant[6655]: wlan0: Association request to the driver failed
Oct 10 01:25:46 KitchenPi dhclient[6659]: No DHCPOFFERS received.
Oct 10 01:25:46 KitchenPi dietpi-wifi-monitor.sh[775]: No DHCPOFFERS received.
Oct 10 01:25:46 KitchenPi dietpi-wifi-monitor.sh[775]: No working leases in persistent database - sleeping.
Oct 10 01:25:46 KitchenPi dhclient[6659]: No working leases in persistent database - sleeping.
Oct 10 01:25:46 KitchenPi dietpi-wifi-monitor.sh[775]: Completed

And on it goes!

Seems like there is an issue getting a new DHCP lease via the reconnect script.

If I reboot the Pi the wifi comes back on immediately.

jptaranto · October 10, 2019, 9:52am

Oh and here is my network config:

dietpi@KitchenPi:~$ cat /etc/network/interfaces
# Location: /etc/network/interfaces
# Please modify network settings via: dietpi-config
# Or create your own drop-ins in: /etc/network/interfaces.d/

# Drop-in configs
source interfaces.d/*

# Local
auto lo
iface lo inet loopback

# Ethernet
#allow-hotplug eth0
iface eth0 inet dhcp
address 0.0.0.0
netmask 0.0.0.0
gateway 0.0.0.0
#dns-nameservers 0.0.0.0

# WiFi
allow-hotplug wlan0
iface wlan0 inet dhcp
address 192.168.1.44
netmask 255.255.255.0
gateway 192.168.1.1
#dns-nameservers 192.168.1.1
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

MichaIng · October 16, 2019, 5:58pm

jptaranto
Many thanks for your report.

We need to suppress the ifdown/ifup output it seems. This doubles with dhclient and wpa_supplicant process outputs and confuses. However yeah dhclient failes to receive an IP. Could you please try:

systemctl disable --now dietpi-wifi-monitor
ifdown wlan0
sleep 10
ifup wlan0

Probably the 1 second time, we give in the script between ifdown and ifup, is not enough in your case.

What you can try as well, is to use a static IP and configure a static lease in your router? In most cases this works just well and reduces the overhead of regular DHCP leases and dhclient background process.

jptaranto · October 18, 2019, 2:17am

Thanks for the reply MichaIng!

I’ve switched over to a static IP now. I’ll see if that helps anything and then try the commands you posted.

muki · October 21, 2019, 8:02pm

This thread saved my day! \o/

jptaranto · October 25, 2019, 2:27am

The static IP made no difference, so I’ve updated the script at

/var/lib/dietpi/services/dietpi-wifi-monitor.sh

with

ifdown $ADAPTER
sleep 10
ifup $ADAPTER

MichaIng · October 25, 2019, 2:47pm

jptaranto
Okay and the sleep 10 indeed solved the issue? Then we need to increase that in our upstream script as well. If you find time, could you try if 2 seconds are enough as well? Raising from 1 to 10 for all would IMO lead to a too long WiFi downtime.

jptaranto · November 14, 2019, 7:59pm

Hey MichaIng, I’m afraid it hasn’t fixed it… but the logs are a little clearer now.

Nov 15 06:20:55 KitchenPi wpa_supplicant[30154]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2412 MHz)
Nov 15 06:20:55 KitchenPi wpa_supplicant[30154]: wlan0: Association request to the driver failed
Nov 15 06:21:07 KitchenPi wpa_supplicant[30154]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2412 MHz)
Nov 15 06:21:07 KitchenPi wpa_supplicant[30154]: wlan0: Association request to the driver failed
Nov 15 06:21:09 KitchenPi dietpi-wifi-monitor.sh[706]: Detected connection loss: wlan0. Reconnecting...
Nov 15 06:21:09 KitchenPi avahi-daemon[770]: Withdrawing address record for 192.168.1.44 on wlan0.
Nov 15 06:21:09 KitchenPi avahi-daemon[770]: Leaving mDNS multicast group on interface wlan0.IPv4 with address 192.168.1.44.
Nov 15 06:21:09 KitchenPi avahi-daemon[770]: Interface wlan0.IPv4 no longer relevant for mDNS.
Nov 15 06:21:10 KitchenPi wpa_supplicant[30154]: nl80211: deinit ifname=wlan0 disabled_11b_rates=0
Nov 15 06:21:10 KitchenPi wpa_supplicant[30154]: wlan0: CTRL-EVENT-TERMINATING
Nov 15 06:21:20 KitchenPi wpa_supplicant[30323]: Successfully initialized wpa_supplicant
Nov 15 06:21:20 KitchenPi kernel: [165035.503378] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
Nov 15 06:21:20 KitchenPi avahi-daemon[770]: Joining mDNS multicast group on interface wlan0.IPv4 with address 192.168.1.44.
Nov 15 06:21:20 KitchenPi avahi-daemon[770]: New relevant interface wlan0.IPv4 for mDNS.
Nov 15 06:21:20 KitchenPi avahi-daemon[770]: Registering new address record for 192.168.1.44 on wlan0.IPv4.
Nov 15 06:21:22 KitchenPi wpa_supplicant[30324]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2412 MHz)
Nov 15 06:21:22 KitchenPi wpa_supplicant[30324]: wlan0: Association request to the driver failed
Nov 15 06:21:24 KitchenPi wpa_supplicant[30324]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2412 MHz)
Nov 15 06:21:24 KitchenPi wpa_supplicant[30324]: wlan0: Association request to the driver failed
Nov 15 06:21:25 KitchenPi wpa_supplicant[30324]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2412 MHz)
Nov 15 06:21:25 KitchenPi wpa_supplicant[30324]: wlan0: Association request to the driver failed
Nov 15 06:21:28 KitchenPi wpa_supplicant[30324]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2412 MHz)
Nov 15 06:21:28 KitchenPi wpa_supplicant[30324]: wlan0: Association request to the driver failed
Nov 15 06:21:35 KitchenPi wpa_supplicant[30324]: wlan0: Trying to associate with f0:9f:c2:fd:8b:24 (SSID='Black Cockatoo' freq=2412 MHz)
Nov 15 06:21:35 KitchenPi wpa_supplicant[30324]: wlan0: Association request to the driver failed
Nov 15 06:21:41 KitchenPi dietpi-wifi-monitor.sh[706]: Completed

I’m looking up this error message and it seems to be common with some wifi setups on rpi.

MichaIng · November 20, 2019, 5:09pm

jptaranto
Hmm, are you sure this is a WPA(2) protected network? WEP requires a different /etc/wpa_supplicant/wpa_supplicant.conf entry, but should - by all means - not be used anymore.

Also, please check that the wpa_supplicant background service is not running, which is not required for ifupdown-based network setups, and might even collide:
systemctl disable --now wpa_supplicant

jptaranto · December 2, 2019, 12:45am

Hey MichaIng, thanks again for keeping up with this. I’ve just got back from some holidays.

It’s definitely a WPA2 network using AES/CCMP encryption.

I’ve run the command you added below. I had heard that wpa_supplicant could collide if it’s already running. It seems to be disabled already however.

dietpi@KitchenPi:~$ systemctl disable --now wpa_supplicant
Failed to disable unit: The name org.freedesktop.PolicyKit1 was not provided by any .service files
dietpi@KitchenPi:~$ systemctl status wpa_supplicant
● wpa_supplicant.service - WPA supplicant
   Loaded: loaded (/lib/systemd/system/wpa_supplicant.service; disabled; vendor preset: enabled)
   Active: inactive (dead)