Can't use internet because networkmanager has disappeared !! (Ubuntu 20.04 LTS)

I need help, and it is quite urgent. I had connections issues (my Wi-Fi connection kept disconnecting)

So I followed what a member of this community recommended, in a similar post written by a fellow member

I entered these commands in a shell

sudo apt-get purge network-manager
sudo apt-get update
sudo apt-get autoremove
sudo apt-get upgrade
sudo apt-get install network-manager
sudo apt install ubuntu-desktop

And now... I don't see any wifi parameters. I can't connect to the internet...

How can I fix this?

Here is what I get when i type sudo dmesg | grep wlo1

1 Answer

In the absense of Network Manager, I suggest that you use netplan. From the terminal, do:

ls /etc/netplan

Find out the name of the file. Make a backup as you will need it after reinstalling NM:

sudo mv /etc/netplan/<file_you_found>.yaml /etc/netplan/<file_you_found>.bak

Now, let’s create a new file:

sudo nano /etc/netplan/config.yaml

Write the file to read:

network: version: 2 renderer: networkd wifis: wlo1: dhcp4: yes dhcp6: yes access-points: "network_ssid_name": password: "**********"

Of course, substitute your details here. Note that the network name and password are enclosed in quotes “.

Netplan is very specific about spacing, indentation, etc., so proofread carefully twice. Save (Ctrrl+o followed by Enter) and exit nano (Ctrl+x followed by Enter).

Follow with:

sudo netplan generate
sudo netplan apply

Did you connect?

iwconfig
ping -c3 

It might take a reboot.

If you are connected, reinstall NM:

sudo apt update
sudo apt install –reinstall network-manager ubuntu-desktop

Reboot and tell us if there is any improvement. If so, I will edit this answer to revert netplan.

EDIT: Now that you are connected and have reinstalled Network Manager, we should revert the netplan file to again refer to NM.

Please do:

 ls /etc/netplan

I assume that the file you backed up is /etc/netplan/01-network-manager-all.bak

If so, first back up the file you just created above:

sudo mv /etc/netplan/config.yaml /etc/netplan/config.bak

And restore the previous file:

sudo mv /etc/netplan/01-network-manager-all.bak /etc/netplan/01-network-manager-all.yaml

Follow with:

sudo netplan generate
sudo netplan apply

You should be all set.