Restricting root logins

Pressing Ctrl-Alt-F4 will give you a prompt for tty3. Note that it is one number less.

Take a look at the contents of /etc/securetty file.

To prevent root from logging in on this device, take out tty3 from this listing. Note, you can always login as another user, then, su to root. Below is an example of the default “/etc/securetty” that allows root to login to everything:

cat /etc/securetty
console vc/1 vc/2 vc/3 vc/4 vc/5 vc/6 vc/7 vc/8 vc/9 vc/10 vc/11 
        tty1 tty2 tty3 tty4 tty5 tty6 tty7 tty8 tty9 tty10 tty11