Add a host for hydra.

nix/configuration/hosts/hydra/vm_disk.nix

@@ -1,24 +1,21 @@
 {
   config,
   lib,
+  pkgs,
   ...
 }:
 
 {
   imports = [ ];
 
-  options.me = {
-    vm_disk.enable = lib.mkOption {
-      type = lib.types.bool;
-      default = false;
-      example = true;
-      description = "Whether we want to mount the local disk for persistent storage.";
-    };
-  };
+  config = {
+    # environment.systemPackages = with pkgs; [
+    #   e2fsprogs # mkfs.ext4
+    #   gptfdisk # cgdisk
+    # ];
 
-  config = lib.mkIf config.me.vm_disk.enable {
     # Mount the local disk
-    fileSystems = {
+    fileSystems = lib.mkIf config.me.mountPersistence {
       "/.disk" = lib.mkForce {
         device = "/dev/nvme0n1p1";
         fsType = "ext4";
@@ -29,6 +26,21 @@
         neededForBoot = true;
       };
 
+      # "/.disk" = lib.mkForce {
+      #   device = "bind9p";
+      #   fsType = "9p";
+      #   options = [
+      #     "noatime"
+      #     "trans=virtio"
+      #     "version=9p2000.L"
+      #     "cache=mmap"
+      #     "msize=512000"
+      #     # "noauto"
+      #     # "x-systemd.automount"
+      #   ];
+      #   neededForBoot = true;
+      # };
+
       "/persist" = {
         fsType = "none";
         device = "/.disk/persist";
@@ -39,6 +51,7 @@
         depends = [
           "/.disk/persist"
         ];
+        neededForBoot = true;
       };
 
       "/state" = {
@@ -51,16 +64,22 @@
         depends = [
           "/.disk/state"
         ];
+        neededForBoot = true;
       };
 
       "/nix/store" = lib.mkForce {
-        fsType = "overlay";
-        device = "overlay";
-        options = [
-          "lowerdir=/nix/.ro-store"
-          "upperdir=/.disk/persist/store"
-          "workdir=/.disk/state/work"
-        ];
+        overlay = {
+          lowerdir = [ "/nix/.ro-store" ];
+          upperdir = "/.disk/persist/store";
+          workdir = "/.disk/state/work";
+        };
+        # fsType = "overlay";
+        # device = "overlay";
+        # options = [
+        #   "lowerdir=/nix/.ro-store"
+        #   "upperdir=/.disk/persist/store"
+        #   "workdir=/.disk/state/work"
+        # ];
         depends = [
           "/nix/.ro-store"
           "/.disk/persist/store"