Forcing user to change their passwords upon login

This is to force a user to change their passwords upon (probably first time) login. As a root, change the password expiration date 0 to ensure user change the password in next login.

You can do the same for the existing user. Just issue chage -d 0 command on the user. User will be prompted to change the password.

You are required to change your password immediately (root enforced)