nixos: fixes for disabling containers by default (#436855)

nixos/doc/manual/administration/imperative-containers.section.md

@@ -2,7 +2,7 @@
 
 We'll cover imperative container management using `nixos-container`
 first. Be aware that container management is currently only possible as
-`root`.
+`root`, and that you need to enable [](#opt-boot.enableContainers) explicitly.
 
 You create a container with identifier `foo` as follows:
 

nixos/modules/profiles/minimal.nix

@@ -30,9 +30,6 @@ in
     fish.generateCompletions = mkDefault false;
   };
 
-  # This pulls in nixos-containers which depends on Perl.
-  boot.enableContainers = mkDefault false;
-
   services = {
     logrotate.enable = mkDefault false;
     udisks2.enable = mkDefault false;

nixos/modules/profiles/perlless.nix

@@ -11,7 +11,6 @@
   system.tools.nixos-generate-config.enable = lib.mkDefault false;
   programs.less.lessopen = lib.mkDefault null;
   programs.command-not-found.enable = lib.mkDefault false;
-  boot.enableContainers = lib.mkDefault false;
   boot.loader.grub.enable = lib.mkDefault false;
   environment.defaultPackages = lib.mkDefault [ ];
   documentation.info.enable = lib.mkDefault false;

nixos/tests/containers-imperative.nix

@@ -19,6 +19,8 @@
     {
       imports = [ ../modules/installer/cd-dvd/channel.nix ];
 
+      boot.enableContainers = true;
+
       # XXX: Sandbox setup fails while trying to hardlink files from the host's
       #      store file system into the prepared chroot directory.
       nix.settings.sandbox = false;

nixos/tests/disable-installer-tools.nix

@@ -11,7 +11,6 @@
     { pkgs, lib, ... }:
     {
       system.disableInstallerTools = true;
-      boot.enableContainers = false;
       environment.defaultPackages = [ ];
     };