Bash – Why the ‘who’ Command Does Not Show ‘root’ as Logged In User

bashrootsusudo

When I log in as root from gnome-terminal using the command:

sudo su

it logs me in as the root user.

Isn't this switching a user considered as a log in?

Also, which command can show me all the "switching" I have done?

Best Answer

First, let's take a look at man who:

Print information about users who are currently logged in.

As you said,

sudo su it logs me as root user

So, it's about you, not about root.

And you are right. This is from man sudo:

sudo allows a permitted user to execute a command as the superuser or
another user, as specified by the security policy.

So, again, when you run sudo su command, in fact you (not root) are executing su command as the superuser.

If you want to became root, first you must to enable root account. See here how to do this:

How to enable root login?

After this you can login with root in tty1-6, via ssh, in GUI at the login screen, etc.

In Ubuntu it seems that there is an alternative to get root logged without to enable his account. The following command will do this:

pkexec env DISPLAY=$DISPLAY XAUTHORITY=$XAUTHORITY gnome-terminal

This will open a root terminal:

root terminal

Related to the second question, I give you a hint: look in /var/log directory for files like auth.log.*.

Related Solutions

Ubuntu – ‘root’ user does not exist

You become root with sudo su (as an example). Or better said: you elevate your admin user to admin priviliges permanently until you exit. Example:

rinzwind@discworld:~$ sudo su
[sudo] password for rinzwind: 
root@discworld:/home/rinzwind#

And no Ubuntu technically does not have an active root user. From the Ubuntu RootSudo wiki page:

In Linux (and Unix in general), there is a SuperUser named Root. The Windows equivalent of Root is Administrators group. The SuperUser can do anything and everything, and thus doing daily work as the SuperUser can be dangerous. You could type a command incorrectly and destroy the system. Ideally, you run as a user that has only the privileges needed for the task at hand. In some cases, this is necessarily Root, but most of the time it is a regular user.

By default, the Root account password is locked in Ubuntu. This means that you cannot login as Root directly or use the su command to become the Root user. However, since the Root account physically exists it is still possible to run programs with root-level privileges. This is where sudo comes in - it allows authorized users (normally "Administrative" users; for further information please refer to AddUsersHowto) to run certain programs as Root without having to know the root password.

This means that in the terminal you should use sudo for commands that require root privileges; simply prepend sudo to all the commands you would normally run as Root. For more extensive usage examples, please see below. Similarly, when you run GUI programs that require root privileges (e.g. the network configuration applet), use graphical sudo and you will also be prompted for a password (more below). Just remember, when sudo asks for a password, it needs YOUR USER password, and not the Root account password.

Ubuntu – Exit from both root and user with one command

Technically, no one answered your question. I appreciate that they think their way is better (probably is), but here's another approach (in case you have to su - some time and have the same issue);

[Log into a system]
$ sudo su -;exit
# echo "do things"
# exit

When you exit from root, the original user will also log out since it's continuing it's last command.

Cheers!

Best Answer

Related Solutions

Ubuntu – ‘root’ user does not exist

Ubuntu – Exit from both root and user with one command

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