Ubuntu: WiFi drops irregularly Ubuntu 16.04 waking from suspend


I recently upgraded to Ubuntu 16.04, previously I was able to suspend the computer and on wake all would work fine. Now, on wake from suspend the WiFi will occasionally drop at irregular intervals. I currently have no way to predict when it happens, but it seems as though it happens more often on unreliable connections in public places.

When it drops, the WiFi does not appear in wicd-curses and wlan0 is dropped in ifconfig.

If I run sudo systemctl restart network-manager.service, I can get the WiFi to work again for upwards of 15 minutes and maybe a maximum of 4 hours. It seems as though running this command does something that enables the WiFi to be restart and it again appears in wicd-curses and ifconfig.

It's workable-ish for now, but sometimes I will be working for over 24 hours or downloading and it's a massive pain. Restarting the machine all of the time is not always convenient. I imagine although my machine is now fairly customised this is not a unique problem to me, although I couldn't find anybody else who had complained online of similar issues.

My questions are:

  • What changed in the update in order to cause this to suddenly start happening?
  • What does the command sudo systemctl restart network-manager.service do that appears to fix the interface with the WiFi card?

My setup is:

  • Dell Latitude E5430
  • Several upgrades as far back as Ubuntu 13 or 14
  • uname -r -> 4.4.0-24-generic

Additionally, I have a sneaking suspicion there is a hardware issue with this model where packets on the USB bus are dropped or don't always get cleared correctly from the buffer. Sometimes keys get stuck until another key is pressed which I think I have to put up with. It happens regardless of the Operating System on the machine. I think the keyboard and WiFi share the same bus as when this has happened in the past the WiFi was significantly slowed until another key was pressed.

I think the issue might have something to do with it not handling connection errors well. If I am trying to connect to a busy AP and get thrown off the WiFi now needs resetting with that command.

All suggestions are welcome!

Note:If u also have question or solution just comment us below or mail us on toontricks1994@gmail.com
Next Post »