Wifi Dropping out? Turn Power Management Off - Informational

[USAFPride]

After you get your device (ZeroW in my case) all nice and bundled up in a box, you may run into a connectivity issue with the wifi disconnecting and not reconnecting necessitating pulling the power. WiFi Power Management needs to be turned off.

Update /etc/network/interfaces and the appropriate wlanx device.

allow-hotplug wlan0
iface wlan0 inet manual
wireless-power off
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

After a reboot iwconfig should show Power Management:off

[andrewshilliday]

Thanks for the info. I was also having WiFi connectivity issues in my own setup (because I had a poor signal out in the garage). Ended up moving the RPI inside and running wires.

[USAFPride]

I still had some intermittent issues after turning Power Management off. For some reason the pi would still drop signal and refuse to reconnect. I added this script checkwifi.sh and CRON job to check the status of the WLAN connection and restart it. This seems to have completely solved the problem. Verify your file name, path, and router address prior to usage.

#!/bin/bash

ping -c4 192.168.0.1  > /dev/null

if [ $? != 0 ]
then
    ifdown --force wlan0
    ifup wlan0
fi

chmod 755 checkwifi.sh and crontab -e or sudo crontab -e */5 * * * * /usr/bin/sudo -H /home/pi/checkwifi.sh >> /dev/null 2>&1

[Poncherelly]

Hello USAFPride, can you share some steps on how to add your script? I'm not very Linux literate but can follow direction like a champ :)

Thanks in advance.

[ncovercash]

Thought I'd note, on Ubuntu Server >18.04 (and likely other distros) that do not use ifupdown (but netplan or something else), the /etc/network/interfaces method does not work, you will need to use something like this (or Poncherelly's solution, although that's a bit more brute-force) (note, you will need sudo):

First, install wireless-tools (with apt or whatever).

Then, append to (or create, if it does not exist) /etc/rc.local before the exit line at the end (if there is one):

iwconfig wlan0 power off

Once you have completed this step, your file should look like:

# Some stuff here optionally
iwconfig wlan0 power off
exit 0 # optional

Finally, make sure the file is executable (chmod +x /etc/rc.local).

Now, on each boot, power save will be disabled! You can confirm this by running iwconfig.