After pulling my hair for several days, I found this: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1638842
/usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf has the following content: [keyfile] unmanaged-devices=*,except:type:wifi,except:type:wwan Removing the file and restarting NetworkManager did the trick. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to network-manager in Ubuntu. https://bugs.launchpad.net/bugs/1658921 Title: NetworkManager does not manage wired connection Status in network-manager package in Ubuntu: Confirmed Bug description: NetworkManager does not manage my wired eth0 connection, no matter how I set /etc/network/interfaces or /etc/NetworkManager/NetworkManager.conf Using ubuntu 16.04, /etc/network/interfaces only managed lo, and [ifupdown] section of NetworkManager.conf had set managed=false. With these same settings, after upgrading to ubuntu 16.10, eth0 appears as unmanaged in nm-applet. If I modify /etc/network/interfaces and add auto eth0 iface eth0 inet dhcp And set managed=true in NetworkManager.conf [ifupdown] section, eth0 is still unmanaged despite it does get an IP from DHCP server. This is happening in my five computers (two laptops and three desktops). To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1658921/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
