add storage to NixNAS

hosts/NixNAS/configuration.nix

@@ -8,6 +8,7 @@
   imports =
     [ # Include the results of the hardware scan.
       ./hardware-configuration.nix
+      ./filesystems.nix
     ];
 
   networking.hostName = "NixNAS";

hosts/NixNAS/filesystems.nix

@@ -0,0 +1,14 @@
+{
+  fileSystems = {
+    "/mnt/hdd" =
+      { device = "/dev/disk/by-label/NixNAS_HDD";
+        fsType = "btrfs";
+        options = [ "discard" ];
+      };
+    "/mnt/ssd" =
+      { device = "/dev/disk/by-label/NixNAS_SSD";
+        fsType = "btrfs";
+        options = [ "discard" ];
+      };
+  }
+}