How to add extra root user to VPS or dedicated server?

Login to your SSH as root user and run the following commands (shown in BLUE color only) to create a new root-priviledged user. To do this, you are going to add the new user to the "wheel" group.

Add a new user to your server: adduser john
Set password for your new user: passwd john  (You will be asked to enter new password)
Add the new user to the wheel group: usermod -a -G wheel john
Ensure 'wheel' group has correct privileges: visudo

Near the bottom of the file you will see these 2 lines:
## Allows people in group wheel to run all commands
# %wheel  ALL=(ALL)       ALL

Simply uncomment (remove the '#') the second line, so it looks like this:
## Allows people in group wheel to run all commands
%wheel  ALL=(ALL)       ALL

Now, the new user john have full root access to your server.

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