network manager says "device not managed"

wired device not managed

Most probably your interface appears in /etc/network/interfaces. By default, NetworkManager does not manage interfaces that appear in /etc/network/interfaces. You can change this behaviour.

To do this - in a terminal:

sudo nano /etc/NetworkManager/NetworkManager.conf

change the line managed=false to managed=true

Save, stop and start network manager:

sudo service network-manager restart

Alternatively, you can remove the interface from /etc/network/interfaces.

backup the current interfaces file:

sudo cp /etc/network/interfaces /etc/network_interfaces_backup

Then open the file:

sudo nano /etc/network/interfaces

Delete everything in that file and copy and paste the following:

auto lo
iface lo inet loopback

Save, stop and start network manager:

sudo service network-manager restart

Double check in network manager (click on the indicator) that you have Enabled Networking ticked and you should also force deletion of old "wired connections" and selecting the new wired connection shown in the network manager indicator.

Ubuntu installs a config file that sets most devices unmanaged:

/usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf:

[keyfile]
unmanaged-devices=*,except:type:wifi,except:type:gsm,except:type:cdma

To disable this, You can create a blank file with the same name in /etc:

sudo touch /etc/NetworkManager/conf.d/10-globally-managed-devices.conf
sudo systemctl restart NetworkManager

wired device not managed

I had the same problem with a fresh install on my Asus Eee PC 1005HA. The live environment worked with no problems, but once installed I couldn't get the connection to respond or to not read "device not managed". When I changed the text in this configuration file and restarted Network Manager everything worked!

gksudo gedit /etc/NetworkManager/NetworkManager.conf

for lubuntu:

gksudo leafpad /etc/NetworkManager/NetworkManager.conf

Now the text editor will open. Find the line managed=false and replace false with true and save the file (ctrl+s) and close the file.

Restart your computer or the NetworkManager service (sudo service network-manager restart).

wireless device not managed

I've also found this issue after installing the Ubuntu 11.10 alternate version.

In my case, the /etc/network/interfaces was configured during installation to download new packages, and the conflict arose after the NetworkManager was set up during the first session.

The solution I've found was commenting the lines related to the wlan interface in the /etc/network/interfaces (in console, sudo vim /etc/network/interfaces or your editor of choice):

# The primary network interface
#auto wlan0
#iface wlan0 inet dhcp
#    wpa-ssid [your_ssid]
#    wpa-psk [your_wpa_password]

And then, as Joseph VanPelt proposed, set managed=false in the /etc/NetworkManager/NetworkManager.conf and running sudo service network-manager restart.

wired device not managed

This is a simple command which does the same as the accepted answer non-interactively.

Run this command in a Terminal to use it:

sudo sed -i 's/^managed=false/managed=true/' /etc/NetworkManager/NetworkManager.conf

You may have to restart the network manager afterwards with this command:

sudo service network-manager restart

All solutions above failed. Here is the solution for Ubuntu 19.10 on minimal install so the odds that this solution works for you are very high.

We are going to edit a file, but you cannot jam everything on one line as this will cause an error. Put [keyfile] on the first line, and the rest of the command on the second line.

sudo nano /etc/NetworkManager/conf.d/10-globally-managed-devices.conf

[keyfile]

unmanaged-devices=*,except:type:wifi,except:type:wwan,except:type:ethernet

ctrl-o to save ctrl-x to close file and nano

Before you reboot, make sure the contents @ /usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf are empty

Explanation, Please Read So you don't screw up: Network-manager presumably looks at both 10-globally-managed-devices.conf files in the two aforementioned directories. If neither of them have [keyfile] seperated by a new line, network-manager crashes (confirmed). If both of them have [keyfile] separated by a new line, presumably as before network-manager will crash (unconfirmed). Presumably [keyfile] means "use this file as config" hence the aforementioned network-manager behavior. So one of those files should be empty and the other should have [keyfile] followed by new line and the rest of the command. So in Ubuntu the /usr/ file will always be zeroed unless possibly way back like 14.04 or earlier. But for other distros it might be reverse where /etc/ file is zeroed and /usr/ file edited and formatted properly.

Ubuntu Jedi Master

Situation like this may appear, when one runs pppoeconf or something similar and the command overwrites the setting saved by NetworkManager. Even though the device seems to be working properly, Network Manager shows device status to be unmanaged.

If this a normal user's pc with simple network configuration like connecting via DHCP and automatic configuration, simply out comment the lines and restart network manager.

$ sudo restart network-manager

If situations other than these, please explain.

I had the same problem, I solved it by commenting the lines where the unmanaged device was mentioned, by mac address, in /etc/NetworkManager/NetworkManager.conf.

[main]
plugins=ifupdown,keyfile
dns=dnsmasq

[ifupdown]
managed=false

[keyfile]
unmanaged-devices=mac:00:26:2d:fd:5c:e0

changed to

[main]
plugins=ifupdown,keyfile
dns=dnsmasq

[ifupdown]
managed=false

\#[keyfile]

\#unmanaged-devices=mac:00:26:2d:fd:5c:e0

There are two ways to manage network connections. You either have to do everything thru the network manager and remove everything Except the Loopback entry in /etc/network/interfaces

auto lo

iface lo inet loopback

or totally remove the network manager thru the package manager or terminal and use the /etc/network/interfaces and /etc/resolve.conf file to control your connections. If not you will see the error you are getting. Even with static IP I've found that the network manager makes things easy and you can configure your IPV4 connections thru the menu.

Just to add a non-default answer, this can also happen if your computer has a hardware ON/OFF switch for the Wi-Fi interface. If you have such a "killswitch", ensure that you haven't accidentally turned the interface off