As long as you are in the admin interface, go to menu option 2, configure server. As you progress through the menus, you will come to an item for login. It is currently set to automatic. Change it to login, and continue through the process without changing anything else. After you exit from the admin screen, it should say your server name:login. Type in root, and hit enter. Then it will ask for the root password. Type in the root/admin password and hit enter. now you should be at a command line interface. To close the interface type exit, or press control d.