nixops & libvirt

commands

Enable KVM and TUN features.

[me:~/]# mkdir /var/lib/libvirt/images

[me:~/]# mkdir lvirt-test
[me:~/]# # add network.nix and network-libvirt.nix from this gist

[me:~/lvirt-test]# export NIXOPS_DEPLOYMENT=test

[me:~/lvirt-test]# nixops create network.nix network-libvirt.nix 
created deployment ‘74f1ffa8-a0b1-11e8-bc0a-0242cdd42284’
74f1ffa8-a0b1-11e8-bc0a-0242cdd42284

[me:~/lvirt-test]# nixops deploy

[me:~/lvirt-test]# nixops ssh hello

network-libvirt.nix

let
  lvirt = {
    deployment.targetEnv = "libvirtd";
    deployment.libvirtd.headless = true;
    #deployment.libvirtd.memorySize = 1024;
    #deployment.libvirtd.vcpu = 2;
    deployment.libvirtd.networks = [ { type="bridge"; source="br0"; } ];

  };
in
{
  network.description = "blah";

  hello     = lvirt;
  #world     = lvirt;
}

network.nix

{
  network.description = "libvirt test";

  hello =
    { config, lib, pkgs, ...}:
    {
      imports = [
        
      ];
      
      services.postgresql.enable = true;
    };
  /*  
  world = 
    { config, lib, pkgs, ...}:
    {
      imports = [
        
      ];
      
    };
  */
}

virt.nix

{ config, lib, pkgs, ... }:

#  include from configuration.nix, change networking.nat.externalIP

let
  nixopsRepo = pkgs.fetchFromGitHub {
    owner = "vpsfreecz";
    repo = "nixops";
    rev = "668a0f9de10c04dbb7df8c1e4f2be7b064834432";
    sha256 = "05ahx1snrddb715r1pdbjk1ywfqa829c6wys9icawxygh2ngspki";
  };
  bridgeName = "br0";
in
{
  nix.useSandbox = false;
  nix.buildCores = 8;
  
  virtualisation.libvirtd.enable = true;
  
  networking.nat = {
    enable = true;
    internalInterfaces = [ "${bridgeName}" ];
    externalInterface = "venet0";
    # Your external IP here
    externalIP = "37.205.14.XZ";
    forwardPorts = [
      # Example
      # { destination = "192.168.122.106:22"; sourcePort = 11122;}
    ];
  };
  
  # libvirt uses 192.168.122.0
  networking.bridges."${bridgeName}".interfaces = [];
  networking.interfaces."${bridgeName}".ipv4.addresses = [
    { address = "192.168.122.1"; prefixLength = 24; }
  ];
  
  services.dhcpd4 = {
    enable = true;
    interfaces = [ "${bridgeName}" ];
    extraConfig = ''
      option routers 192.168.122.1;
      option broadcast-address 192.168.122.255;
      option subnet-mask 255.255.255.0;
  
      option domain-name-servers 37.205.9.100, 37.205.10.88, 1.1.1.1;
  
      #default-lease-time -1;
      #max-lease-time -1;
  
      subnet 192.168.122.0 netmask 255.255.255.0 {
        range 192.168.122.100 192.168.122.200;
      }
    '';
  };

  nixpkgs.overlays = [
    (self: super:
      {
        nixops = (import "${nixopsRepo}/release.nix" {}).build.x86_64-linux;
      }
    )
  ];

  environment.systemPackages = with pkgs; [
    screen
    nixops
    git
  ];

}