Nixops - deploy to VirtualBox

This will create a VM in VirtualBox and deploy web server (and an openssh server) inside it.

VirtualBox

First thing to do it to install VirtualBox. Modify the nixos configuration.nix and add the following lines:

File: configuration.nix

  nixpkgs.config.allowUnfree = true;

  virtualisation.virtualbox.host.enable = true;
  virtualisation.virtualbox.host.enableExtensionPack = true;
  users.extraGroups.vboxusers.members = [ "lontivero" ];

The allowUnfree = true is because the extension pack is not free. I am not sure the extension pack is needed, anyway.

Then sudo nixos-rebuild switch

Deployment

Defining the deployment

Two files need to be created:

File: trivial.nix

{
  network.description = "The Simplest Web server";
  webserver =
    { config, pkgs, ... }:
    {
      services.openssh = {
        enable = true;
        passwordAuthentication = false;
        permitRootLogin = "yes";
      };
      #users.users."root".openssh.authorizedKeys.keys = [
      #   "ssh-rsa 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 lontivero@lontivero-MAX-G5"
      #];

      services.httpd.enable = true;
      services.httpd.adminAddr = "alice@example.org";
      networking.firewall.allowedTCPPorts = [ 22 80 ];

      services.httpd.logFormat = "combined";
      services.httpd.virtualHosts = {
        "main" = {
          documentRoot = "/tmp";
        };
      };
    };
}

trivial-vbox.nix

{
  webserver =
    { config, pkgs, ... }:
    { deployment.targetEnv = "virtualbox";
      deployment.virtualbox.memorySize = 1024; # megabytes
      deployment.virtualbox.vcpu = 2; # number of cpus
      deployment.virtualbox.headless = true;
    };
}

NOTE: using headless = true prevents the VirtualBox GUI console to appears, what is exactly what we want, but we can open it manually anyway and see the VM.

Creating the deployment

This of all we have to install nixops.

Install Nixops

Installing nixops fails because it is marked as insecure so, the easiest way to bypass that is as follow:

$ NIXPKGS_ALLOW_INSECURE=1 nix-shell -p nixops

Create and deploy

$ nixops create ./trivial.nix ./trivial-vbox.nix -d trivial
$ nixops deploy -d trivial

At this point we should have a VM running, however it can happen that nixops fails to connect to the VM through SSH with too many attemps. To fix this add indentitiesOnly yes to the .ssh/config file.

SSH session

We can get access to the VM using:

$ nixops ssh -d trivial webserver

$ nixops info -d trivial
$ nixops destroy -d trivial
$ nixops delete -d trivial
$ rm -rf ~/nixops

Test it

$ curl 192.168.56.111
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<html>
 <head>
  <title>Index of /</title>
 </head>
 <body>
<h1>Index of /</h1>
  <table>
   <tr><th valign="top"><img src="/icons/blank.gif" alt="[ICO]"></th><th><a href="?C=N;O=D">Name</a></th><th><a href="?C=M;O=A">Last modified</a></th><th><a href="?C=S;O=A">Size</a></th><th><a href="?C=D;O=A">Description</a></th></tr>
   <tr><th colspan="5"><hr></th></tr>
   <tr><th colspan="5"><hr></th></tr>
</table>
</body></html>