give unbound fixed ip address

hosts/fw.cloonar.com/modules/unbound.nix

@@ -156,7 +156,10 @@ in {
       networking = {
         hostName = "ns";
         interfaces.mv-vserver = {
-          useDHCP = true;
+          ipv4.addresses = [{
+            address = "10.42.97.2";
+            prefixLength = 24;
+          }];
         };
         firewall = {
           enable = true;