nixos/modules/services/networking/netns.nix

   1 { pkgs, lib, config, ... }:
   2 {
   3 systemd.services."netns@" = {
   4   description = "%I network namespace";
   5   before = [ "network.target" ];
   6   serviceConfig = {
   7     Type = "oneshot";
   8     RemainAfterExit = true;
   9     PrivateNetwork = true;
  10     ExecStart = "${pkgs.iproute}/bin/ip netns add %i";
  11     ExecStop = "${pkgs.iproute}/bin/ip netns del %i";
  12   };
  13 };
  14 }