When I type sudo [command] it prompts for my password and after I enter it it tells me that i'm not in the sudoers file. How do i fix this?

As unprivileged user run 'man sudoers'. The manual page should show you how the /etc/sudoers file should be used. Log in as root user and run 'less /etc/sudoers'. Reading /etc/sudoers will show you examples you could adapt to your needs. Now run 'visudo' to edit /etc/sudoers. Please do not use any other editor as visudo checks for syntax errors when you write out the file to disk.

Ok, thx, can i just use su in fedora like sudo in ubuntu?

I never bother with setting up sudo. What's wrong with typing "su" and giving the root password?

If you want to edit /etc/sudoers, then enter "EDITOR=nano" before using "visudo". You really don't want to be exposed to sudoers and vi at the same time!

you can set it ( not set by default) if you want . But i never found a good ( or bad) reason to do so .
use su or " su - "
"su - " is preferred

the two commands do different things

Sort of - is the closest equivalent. "su" (or "su -") actually cause you to become the root user - see the manpage (su requires the root password, not yours like {usually} sudo).

Now wait for this to become a flamefest re unleashing the four horsemen of the Apocalypse by even suggesting "su" usage.

that is a old and LONG flame

yes there is a security hole with sudo ,but if set up correctly ,(as far as i know there are no exploits in the wild )

it is more personal choice
one or the other .

Thanks for the info.

You might (or perhaps not) be interested in the background. To use "su", you obviously need to know the root password, and you can then do anything. To use "sudo", you use your own password and it's possible to set the permission to apply only to set commands, rather than to everything as in Ubuntu.

Think of an enterprise situation. A system administrator comes to help someone. They use "su" to take control of the computer. The same administrator wants to delegate a particular task to one or more reliable people. They put the trustees in the sudoers file, with permission to carry out a specific job. When these people use that privilege, they give their password to prove it's not just anyone sitting in their seat.

With your own computer at home, it seldom matters what you use. People just like arguing about it, like Gnome vs KDE, or vi vs emacs.

I found this difficult, because it would give me the error "can't use insert in vi mode" (or something to that effect). I don't know vi very well to begin with, so this idea of "vi mode" in nano not allowing me to insert text drove me nuts! (After all, what's the point?)

As others have said, though, using "visudo" verifies the file before writing it. But if you're making a simple change and pretty confident you won't screw it up, there's an easier way:

Added to "sudoers" to allow a user to run "updatedb" to update the database for slocate:
I had to also add this user to the "wheel" group (edit /etc/group):
I put my actual username, not "username”

This works, but bizarrely, I am not asked for a password...supposedly, sudo should ask for my user's password by default. Maybe I am misunderstanding something.

the reason vi was not working using the " su " command on fedora
is that MOST things will also NEED the root $PATH also
use " su - "