Sstrhsrtj

I installed and am trying to get started with NixOS, and am trying to add my user to the sudoers file.

So that I'm not running all my commands as root I created a user following Chapter 7. User Management of the NixOS manual. That is, I ran

# useradd -m matthew

# su - matthew -c "true"

# passwd matthew

Enter new UNIX password: ***

Retype new UNIX password: ***

And also I added

users.extraUsers.matthew = {

    isNormalUser = true;

    home = "/home/matthew";

    extragroups = [ "wheel" "networkmanager" ];

}

to /etc/nixos/configuration.nix. But still I am not able to run sudo as matthew.
For example, when I try to open sudo's man page with sudo, I get the matthew is not in the sudoers file error.

$ sudo man sudo

[sudo] password for matthew:

matthew is not in the sudoers file. This incident will be reported.

Then I tried following advice on how to add a user to the sudoers file in other distributions, namely editing with $ visudo. But when I run that, nixos tells me not to edit that file. That is, running

$ visudo

opens /etc/sudoers.tmp with first line reading

# Don't edit this file. Set the NixOS option ‘security.sudo.configFile’ instead.

How do I set the NixOS option ‘security.sudo.configFile’?

Firstly, adding the user with useradd and editing users.extraUsers is redundant. I've never bothered with useradd on NixOS.

As for the sudo configuration, what you do is set the attribute to a string containing what you'd normally put into sudoers.

...

security.sudo.configFile = ''

   Sudoers config goes here

''

...

My guess is that in your case, the problem comes from the fact that you created the same user both imperatively (with useradd) and declaratively (in configuration.nix).

First of all, make sure that you run nixos-rebuild switch after each change to /etc/nixos/configuration.nix. Second, if that is not enough, it is probably that the options that you passed declaratively cannot be used given that the user was already created. In which case, removing the user first and running nixos-rebuild switch then should solve the issue.

Adding a user to the wheel group should be sufficient to gain sudo privileges.

After you've added a user to a new linux group, you need to logout and login those users, for those changes to take effect (new group).