‘Authentication Required’ when open the network setting

Problem

This error is reported with Linux 5.10 on Ubuntu 20.10, a dialog box pop-up with Authentication Required and request password but actually cannot change the network settings whilist the network is working.

Workaround

By adding or modifying the file /etc/netplan/50-cloud-init.yaml, the menu is changed to ‘Wired Connected’ from ‘Wired Unamaged’ after rebooting.

network:
  renderer: NetworkManager
  ethernets:
    eth0:
      dhcp4: true
  version: 2

See also

• No wired connection - Wired unmanaged ubuntu 18.04
• Ethernet connection not working on Ubuntu 20.04