many changes and more modularizing

hosts/fw/modules/snapserver.nix

@@ -1,6 +1,7 @@
 { pkgs, config, python3Packages, ... }:
 let
   domain = "snapcast.cloonar.com";
+  networkPrefix = config.networkPrefix;
 
   snapweb = pkgs.stdenv.mkDerivation {
     pname = "snapweb";
@@ -28,8 +29,8 @@ in
     ephemeral = false; # because of ssh key
     privateNetwork = true;
     hostBridge = "server";
-    hostAddress = "10.42.97.1";
-    localAddress = "10.42.97.21/24";
+    hostAddress = "${networkPrefix}.97.1";
+    localAddress = "${networkPrefix}.97.21/24";
     bindMounts = {
       "/var/lib/acme/snapcast/" = {
         hostPath = "${config.security.acme.certs.${domain}.directory}";
@@ -53,10 +54,10 @@ in
         hostName = "snapcast";
         useHostResolvConf = false;
         defaultGateway = {
-          address = "10.42.96.1";
+          address = "${networkPrefix}.96.1";
           interface = "eth0";
         };
-        nameservers = [ "10.42.97.1" ];
+        nameservers = [ "${networkPrefix}.97.1" ];
         firewall.enable = false;
       };
       environment.etc = {