cant add user to sudo group in centOS 7 i386(no GUI,Its minimal) I had install centOS 7 minimal version in my virtualbox in Ubuntu mate. It has no GUI. It is totally CLI. My user name is `Smit` and able to login in to it. But when i type command sudo yum update and enter my password, it says Smit is not in sudoers files. This incident will be reported. But when I try to add my user to `sudo` group by command adduser Smit sudo gives something like this: 

I don't know why your command doesn't work. It may have to do with either:

* your CentOS not using sudo by default
* the way the sudoers file should be edited
* the syntax of `adduser` command on that particular machine.



Apparently, and it is my guess, it's first of all a matter of the last point.

Anyhow, the easiest way is to add the user to the `wheel` group, which should have sudo priviliges on your CentOS. Try out this command:


usermod -aG wheel Smit


This of course has to be done by `root`. Once successfully executed, change identity to `Smit` and check if you can `sudo`.


su - Smit
sudo yum update


As an alternative, you can use `visudo`. Adding this line should do:


Smit ALL=(ALL) ALL


But here's a guide with a few more details if you're interested.