Disable LLMNR.

It should hopefully fix the issue where network doesn't come back after
a system config switch.

hosts/chilly/default.nix

@@ -40,19 +40,33 @@
 
   users.users.ppetru.extraGroups = [ "libvirtd" ];
 
-  networking = {
-    # TODO: try using DHCP for br0. will probably need a hardcoded MAC
-    defaultGateway = "192.168.1.1";
-    nameservers = [ "192.168.1.1" ];
-    bridges.br0.interfaces = [ "enp1s0" ];
-    interfaces.br0 = {
-      useDHCP = false;
-      ipv4.addresses = [
-        {
-          "address" = "192.168.1.5";
-          "prefixLength" = 24;
-        }
-      ];
-    };
+  networking.useNetworkd = true;
+  systemd.network.enable = true;
+  # not useful and potentially a security loophole
+  services.resolved.llmnr = "false";
+
+  systemd.network.netdevs."10-br0" = {
+	netdevConfig = {
+	  Name = "br0";
+	  Kind = "bridge";
+      # when switching to DHCP, fill this in with value from enp1s0 or something made up starting with 02:
+      # MACAddress = "";
+	};
+  };
+
+  systemd.network.networks."20-enp1s0" = {
+	matchConfig.Name = "enp1s0";
+	networkConfig.Bridge = "br0";
+  };
+
+  systemd.network.networks."30-br0" = {
+	matchConfig.Name = "br0";
+	networkConfig = {
+      # TODO: use DHCP. Would need a hardcoded MAC (see above)
+	  Address = [ "192.168.1.5/24" ];
+	  Gateway = [ "192.168.1.1" ];
+	  DNS = [ "192.168.1.1" ];
+      # DHCP = "yes";
+	};
   };
 }