Create a sudo user in CentOS

This article describes the process of granting sudo access to a new or existing user on CentOS®.

Create a new user

Create a new user by using the adduser command followed by the new user's <username> as shown in the following example:
```
[root@server-01 ~]# adduser newuser
```

Use the passwd command followed by the new user's <username> to set up a password for newuser. Enter the new password in the verification prompt twice.

[root@server-01 ~]# passwd newuser
Changing password for user newuser.
New password:
Retype new password:
passwd: all authentication tokens updated successfully

Grant root permissions to a new or existing user

Edit the sudoers file by using the following command:
```
[root@server-01 ~]# visudo
```

You then see a version similar to following text:

## Next comes the main part: which users can run what software on
## which machines (the sudoers file can be shared between multiple
## systems).
## Syntax:
##
##      user    MACHINE=COMMANDS
##
## The COMMANDS section may have other options added to it.
##
## Allow root to run any commands anywhere
root    ALL=(ALL)       ALL

## Allows members of the 'sys' group to run networking, software,
## service management apps and more.
# %sys ALL = NETWORKING, SOFTWARE, SERVICES, STORAGE, DELEGATING, PROCESSES, LOCATE, DRIVERS

## Allows people in group wheel to run all commands
%wheel  ALL=(ALL)       ALL

## Same thing without a password
# %wheel        ALL=(ALL)       NOPASSWD: ALL

## Allows members of the users group to mount and unmount the
## cdrom as root
# %users  ALL=/sbin/mount /mnt/cdrom, /sbin/umount /mnt/cdrom

## Allows members of the users group to shutdown this system
# %users  localhost=/sbin/shutdown -h now

## Read drop-in files from /etc/sudoers.d (the # here does not mean a comment)
#includedir /etc/sudoers.d

Press the i key on your keyboard to enter insert mode. Next press the j key to move the cursor down and the k key to move it up to the following section:
```
## Allow root to run any commands anywhere
root    ALL=(ALL)       ALL
```
Add the newly created user by inserting <username> ALL=(ALL) ALL on a new line as show in the following example:
```
## Allow root to run any commands anywhere
root    ALL=(ALL)       ALL
newuser ALL=(ALL)       ALL
```
Press the i key to exit insert mode, followed by typing :wq to save and exit.

Verify permission change

Use the su command followed by - <username> to access the new user account.
```
[root@server-01 ~]# su - newuser
[newuser@server-01 ~]$ 
```

Use the sudo -i command to test if the new user account can elevate permissions. Enter the new user's password. Verify these steps by using the following example:

[newuser@server-01 ~]$ sudo -i

We trust you have received the usual lecture from the local System
Administrator. It usually boils down to these three things:

 #1) Respect the privacy of others.
 #2) Think before you type.
 #3) With great power comes great responsibility.

[sudo] password for newuser:
[root@server-01 ~]#

Use the whoami command to verify you are currently the root user.
```
[root@server-01 ~]# whoami
root
```

Updated about 1 year ago