How can I prevent iwconfig power management from being turned on?

Question

I am affected by this bug: 869502.

A workaround which seems to stop the kernel panics for me is to disable wlan0 power management:

sudo iwconfig wlan0 power off

However it seems to automatically turn power management back on when I unplug the power cable and I think at many other times, too.

Is there something that might be causing this? Does anyone know how I can prevent it?

Solution 1

Wireless powermanagement is run by a hook in pm-utils. You can turn it off in any of the following way:

Create a file in /etc/pm/config.d. I have named it blacklist:

gksu gedit /etc/pm/config.d/blacklist

and inside the file keep:

HOOK_BLACKLIST="wireless"

If you want to disable any other hooks, default hooks are located at /usr/lib/pm-utils/power.d/.

OR

You can just create an empty hook in either /etc/pm/sleep.d or /etc/pm/power.d. See which one works for you. i.e.

Just do

sudo touch /etc/pm/sleep.d/wireless

OR

sudo touch /etc/pm/power.d/wireless

Solution 2

Type iwconfig and look at the output. You should see the name of your chip-set as well as the whether power management is off or on. If it doesn't say, it is probably off.

To turn off power management, go to /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf and you will see

[connection]
wifi.powersave = 3

Change the 3 to a 2 and reboot.

Then run iwconfig and if it worked you should see Power Management:off.

Source: https://sites.google.com/site/easylinuxtipsproject/internet

Solution 3

If turning off power management for your wireless interface speeds up internet like this:

sudo iwconfig wlan0 power off

Than to make it permanent run command as follows:

1. cd /etc/pm/power.d

2. sudo gedit wifi_pwr_off

   This will open an empty file, copy the code below into it:

   #!/bin/sh 
   /sbin/iwconfig wlan0 power off
   

3. Save the file, remember to

   sudo chmod +x wifi_pwr_off
   

   and restart.

Solution 4

My preferred way is to add the following line in /etc/network/interfaces to my wireless interface's settings:

post-up iwconfig wlan0 power off

Here's a complete example:

auto wlan0
iface wlan0 inet static
 address 192.168.1.2
 network 192.168.1.0
 netmask 255.255.255.0
 broadcast 192.168.1.255
 gateway 192.168.1.254
 post-up iwconfig wlan0 power off
 wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

Note that man interfaces says the behaviour of post-up may change in the future.

Solution 5

For some reason, the top-voted solutions didn't work for me and power management kept turning back on. I ended up doing the following:

sudo gedit /etc/rc.local

And added the following line before exit 0:

( sleep 30 && iwconfig wlan0 power off )&

That turns off power management 30 seconds after logging in...

Edit: Actually that wasn't enough. I kept trying a bunch of stuff, including https://askubuntu.com/a/614245 which I think solved my problem (I hope).

View more solutions

Comments

[Qasim]

askubuntu.com/questions/285434/…

[Ufos]

7 years and counting. Is this a bug or a feature?

[Ufos]

unix.stackexchange.com/a/315400/126119

[Alex]

I used the first method. It's working. Thanks!

[Mihai Capotă]

None of the methods work for me.

[Murhaf Sousli]

When i write sudo iwconfig wlan0 power off i get this message : Error for wireless request "Set Power Management" (8B2C) : SET failed on device wlan0 ; No such device.

[Meghna Natraj]

Run iwconfig without any agrument sudo iwconfig and check which interface has wireless extension. Sometimes it is eth1.

[RyanNerd]

I hope this works. I hope, I hope, I hope!!! Tired of Linux tossing my wifi connection at random times. /rant Ubuntu 16.04 has some major issues here /endrant

[Emad Arshad Alam]

could we do chmod -x /usr/lib/pm-utils/power.d/wireless instead ?

[user3273814]

This seemed to turn off my power management!

[RyanNerd]

Nope didn't work. Intel 7260 is a piece of crap! I've given up.

[MerlinTheMagic]

This solution is far better than scripting a power off. The solutions involving a sleep before the power off is that if the client fails to associate before the sleep expires wlan0 stays down, even when the network comes within range.

[Jagoliveira]

This option works like a charm on Raspbian Stretch. For me is the better option.

[Ufos]

this also seems to be the right way to do it

[josephwb]

This worked for me on Ubuntu 17.10. Seems far more straightforward and easily reversible than the other approaches (e.g. blacklisting).

[Abdul Rauf]

worked perfectly in Ubuntu 20.04 for Qualcomm atheros QCA9377

[Danijel]

Here are all the possible values and the meaning: NM_SETTING_WIRELESS_POWERSAVE_DEFAULT (0): use the default value NM_SETTING_WIRELESS_POWERSAVE_IGNORE (1): don't touch existing setting NM_SETTING_WIRELESS_POWERSAVE_DISABLE (2): disable powersave NM_SETTING_WIRELESS_POWERSAVE_ENABLE (3): enable powersave. The source: gist.github.com/jcberthon/ea8cfe278998968ba7c5a95344bc8b55.

[Phantômaxx]

I don't have the gksu command (Ubuntu Studio 20.10).

[yelly]

Great answer. Thanks a lot!

[Mehdi]

This answer seems limited to Network Manager usage...