Raspberry Pi Stack Exchange is a question and answer site for users and developers of hardware and software for Raspberry Pi. It only takes a minute to sign up.
Sign up to join this community
I'm trying to disable the wireless power save on my RPI3, but can't do it:
$ sudo iwconfig wlan0 power off
Error for wireless request "Set Power Management" (8B2C):
SET failed on device wlan0 ; Invalid argument.
Is it possible, or simply not supported?
Regardless, if I don't get any problems while using the wifi card as Soft AP, is there any advantage is disabling power management?
upgrade to "next" firmware branch:
sudo BRANCH=next rpi-update
mine is now kernel 4.4.3 and firmware 41f8b4812ad653abf321b8c54cb4bee57ebdb129 and now accepts the power off command. My connection was constantly dropping, this appears to have sorted it!
I'm running current kernel (4.1.19-v7+ #853), which exhibits the problem. Updating to BRANCH=next didn't help, so I rolled back.
For me, although iwconfig wlan0 power off doesn't work, the alternative iw dev wlan0 set power_save off does work.
So I've commented-out wireless-power off in /etc/network/interfaces, and replaced by:
allow-hotplug wlan0
iface wlan0 inet manual
# wireless-power off
post-up iw dev $IFACE set power_save off
Try
sudo iw dev wlan0 set power_save off
Here's a way I used that should work on any Pi- or any Debian Based distro on a Pi- to PERSISTENTLY disable Power Management as a systemd service.
Just copy the below bash script into a file, chmod 700 it and sudo ./fileName will setup a service that ensures Power Management stays down across reboots. Tested and known to work correctly on Raspbian Buster:
if [ -d /root/scripts ]; then
mkdir /root/scripts
fi
apt-get -y install iw
apt-get -y install wireless-tools
cat <<EOF> /root/scripts/pwr-mgmnt-wifi-disable.sh
#!/bin/bash
iw dev wlan0 set power_save off
EOF
chmod 700 /root/scripts/pwr-mgmnt-wifi-disable.sh
cat <<EOF> /etc/systemd/system//pwr-mgmnt-wifi-disable.service
[Unit]
Description=Disable WiFi Power Management
Requires=network-online.target
After=hostapd.service
[Service]
User=root
Group=root
Type=oneshot
ExecStart=/root/scripts/pwr-mgmnt-wifi-disable.sh
[Install]
WantedBy=multi-user.target
EOF
chmod 644 /etc/systemd/system/pwr-mgmnt-wifi-disable.service
systemctl enable pwr-mgmnt-wifi-disable.service
systemctl start pwr-mgmnt-wifi-disable.service
User=root and Group=root is not needed, that's default. Why using a bash script? ExecStart=/sbin/iw dev wlan0 set power_save off will do the same job. Installing iw and wireless-tools is not needed. They are available out of the box.
iw is key to the solution, I expressly describe it as required. The bash script is merely to install the service.