Network Manager crash out of nowhere Ubuntu 20.04

Question

Basically, once in a while, the Network Manager dies out of nowhere. The computer still seems connected to the wifi but it says there is no connection to the internet; When I try to open the wifi settings I get the "Oops, something has gone wrong. Please contact your software vendor. NetworkManager needs to be running". Moreover, everything looks incredibly slow, When I try to run any sudo command in the terminal to try to restart the network manager it just does nothing and let me in "blank space" in the terminal. Plus I can't turn off the computer from the Power off/Log Out option, and I have to restart it from the mechanical button. Once restarted it works, but it's extremely annoying and unpredictable, plus, working on cloud systems, it causes me to lose stuff most of the times it happens.

Answer 1

I had the exact same issue/symptoms two weeks ago, when I changed apartment and my computer was connecting to a new router.

I solved it by updating my kernel to the latest mainline. Since then I did not have any issue again (until now).

You can find alternative ways to update your kernel here: https://linuxhint.com/update_ubuntu_kernel_20_04/

Answer 2

I am new to ubuntu linux and had the same problem. At first I didn't have any network connection - no wifi and no wired connections. The fix for wifi connection problem was to remove unnecessary character from wifi powersave options file. To open the file run:

sudo nano /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf

The file should contain only the following:

[connection] wifi.powersave = 3

The wired connection problem got fixed when I rewrote the content in the following file. To open it run:

sudo nano /etc/netplan/01-network-manager-all.yaml

The file content which I used to fix the issue:

network:
  version: 2
  renderer: NetworkManager

Hope this helps.