NetworkManager: Use a Wired Connection to Join a Domain

On Linux computers running NetworkManager, which is often used for wireless connections, you must make sure before you join a domain that the computer has a non-wireless network connection and that the non-wireless connection is configured to start when the networking cable is plugged in. You must continue to use the non-wireless network connection during the post-join process of restarting your computer and logging on with your Active Directory domain credentials.

After you join the domain and log on for the first time with your AD domain credentials using a non-wireless connection, you can then revert to using your wireless connection because your AD logon credentials are cached (You will not, however, be notified when your AD password is set to expire until you either run a sudo command or log on using a non-wireless connection).

If, instead, you attempt to use a wireless connection when you join the domain, you cannot log into your computer with AD domain credentials after your computer restarts.

Here is why: NetworkManager is composed of a daemon that runs at startup and a user-mode application that runs only after you log on. NetworkManager is typically configured to auto-start wired network connections when they are plugged in and wireless connections when they are detected. The problem is that the wireless network is not detected until the user-mode application starts, which occurs only after you log on.

For more information about NetworkManager, please see NetworkManager - GNOME Wiki!.