Before we go back into the world of Linux (having spent time in the world of networking), let’s talk about users again.  In particular, the SuperUser also known as Root.  Root is his every day name, SuperUser is his power!  And with great power comes great responsibility.

Groot not Root

That’s Groot, not root, even though they rhyme.  Groot is a superhero, root is a superuser, and root doesn’t go around saying ‘I am Groot’ all the time.  They’re both super though.

SuperUsers’s great power is that he can do anything on a system and  I do mean, anything.  You change the permissions on your file so that you’re the only one that can see it?  Well, the superuser can see it too. He’s all powerful like Superman, but without that annoying green rock allergy.

His username is root and because he’s so powerful, he shouldn’t be logged in unless he’s absolutely needed.  The administrator of your system shouldn’t keep him logged in, but there’s a command to see who is logged in.  It’s called who.

Alpha:~ computerlamp$ who
computerlamp  console  Mar 17 08:01

There I am, logged into the system and I don’t have root logged into my system right now and that’s a good thing.

Since root is a user, he (or she!) has a password.  If you know the password, you can become root.  Like IronMan putting on his suit or BatMan suiting up, you can put on the root armor and be… SuperUser!  And like I always say, there’s a command for that.  This one is called su.

Alpha:~ computerlamp$ su
Password:
Alpha:~ :~ root#

You have to know the password in order for it to work.  If you don’t know the password, don’t try to do this.  It means you don’t have the permission to do it and if you try, you’re attempting to go around the system’s security and that’s a bad thing.  It’s like trying to lift Thor’s hammer and you’re not worthy.

If your root password gets out, then that’s a security problem.  When we made the shield group to hide the helicarrier plans, we thought we were safe from prying eyes.  But if Hydra got the root password, it wouldn’t matter.  That’s why it’s so important to keep that root password safe. The administrator of the system shouldn’t share it with anyone who doesn’t absolutely need it.