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- The preferred way to
run administrative tasks

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is by using sudo.

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That is because sudo
is more sophisticated.

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It allows you to grant users privileges to

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learn specific tasks or all
tasks with elevated permissions.

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In admin, it's either you
are root, or you are not,

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and in sudo, you can go for
the solution in the middle.

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You can create a
configuration where a user

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just has access to a
limited couple of tasks.

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The default "admin" user has
sudo privileges by default.

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But what is this default "admin" user?

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Well, this default "admin" user

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is a user that may be created

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while installing your Linux distribution.

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Depends on your installation options.

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So watch your installation
options to make sure

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that you do have an admin
user, but normally you should.

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On Red Hat, you will be an admin user

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if you are a member of the group wheel.

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And notice that on Red Hat,

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when a root user is
created with a password,

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there is no default "admin" user.

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You need to specifically
grant administrator privileges

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to a user account while installing

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if you wanna have this
default "admin" user.

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I will show you in one of the
next lessons managing users,

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how you can create admin users later.

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It's not that difficult,
but let's not do that now.

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On Ubuntu, the default "admin" user

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is a member of the group sudo.

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As a sudo enabled user,

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you use sudo followed by the
command that you want to run

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with the escalated privileges.

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Or alternatively, you can use
sudo - i to open a root shell,

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which is not recommended,
but it's an option.

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Let me show you sudo.

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So the first thing to investigate
sudo is the id command.

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What is this command?

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Well, this command is showing the groups

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that you are currently a member of.

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I'm old centos here, and as you can see,

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I'm a member of the group wheel,

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which means that I can run
tasks with sudo privileges.

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Just to make sure that you get it,

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I'm using ls - l /root

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And what is it giving me?

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That's giving me permission denied.

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I'm using the up arrow to
repeat the last command.

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And now I'm using control a

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to go to the start of the command line,

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followed by sudo ls - l.

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And I'm prompted for the
root password, that is okay.

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Here we go.

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I can see the contents of the
root directory at this point.

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Now the thing is that if you use sudo

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in front of an ls command,

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then only the ls command is executed

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with administrative privileges.

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And right now I'm back in
my ordinary user shell.

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And that's exact exactly
how I want it to be.

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Alternatively, you can use sudo - i,

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which is giving you access
to a complete root shell.

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Not recommended.

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But if it's not recommended
why would you wanna do it?

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Well, sometimes you need
to do administration.

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And if you are going to
work as an administrator,

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then you might want to be in a sudo shell

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for the entire day and
then this is convenient.

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At the end of being in a sudo shell,

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you need to type exit to get out of there.

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An alternative way is sudo su -

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Now, what is the difference?

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Well, sudo su - is using the su mechanism

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to open a root shell,

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and effectively the result is the same.

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Now, is there any difference on Ubuntu?

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Let's go check it out.

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On Ubuntu, if I type id,

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then I can see that the user
is a member of the adm group.

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And the user is also a
member of the sudo group.

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And basically both of them
are granting sudo privileges.

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So sudo ls - l /root

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is prompting for the
password, as expected.

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I'm entering the password.

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And I can see the contents
of the directory /root.

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And also sudo - i works on Ubuntu

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and sudo su - works on Ubuntu.

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So between the Linux distributions,

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there is no real difference in using sudo.

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The only difference is in
how you are making sure

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that the user is becoming
administrative user

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but that's more about user groups,

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a topic that we will talk about later.