diff --git a/systems/auth-dns.noc.eh22.intern.nix b/systems/auth-dns.noc.eh22.intern.nix
index 153c5b2..e730cbd 100644
--- a/systems/auth-dns.noc.eh22.intern.nix
+++ b/systems/auth-dns.noc.eh22.intern.nix
@@ -34,6 +34,19 @@ in
 {
   imports = [ ];
 
+  # configure static IP address
+  networking.useDHCP = false;
+  systemd.network = {
+    enable = true;
+    networks = {
+      "10-mgmtNet" = {
+        matchConfig.MACAddress = "bc:24:11:c1:8a:a4";
+        address = [ "10.20.25.3/24" ];
+        gateway = [ "10.20.25.2" ];
+      };
+    };
+  };
+
   # enable knot authorative dns server
   # ref: https://search.nüschtos.de/?query=services.knot
   #      https://www.knot-dns.cz/docs/3.4/html/configuration.html
diff --git a/systems/sketchy-router.noc.eh22.intern.nix b/systems/sketchy-router.noc.eh22.intern.nix
index feeba88..caf27b5 100644
--- a/systems/sketchy-router.noc.eh22.intern.nix
+++ b/systems/sketchy-router.noc.eh22.intern.nix
@@ -2,6 +2,17 @@
   pkgs,
   ...
 }:
+let
+  renameLink = macAddr: newName: {
+    matchConfig = {
+      MACAddress = macAddr;
+      Type = "ether";
+    };
+    linkConfig = {
+      Name = newName;
+    };
+  };
+in
 {
   imports = [ ];
 
@@ -14,14 +25,18 @@
   networking.nftables.enable = true;
   systemd.network = {
     enable = true;
+    links = {
+      "10-ethUpstream" = renameLink "BC:24:11:D2:69:8D" "ethUpstream";
+      "10-ethMgmt" = renameLink "BC:24:11:A3:38:4E" "ethMgmt";
+    };
     networks = {
       "10-ethUpstream" = {
-        matchConfig.MACAddress = "BC:24:11:D2:69:8D";
+        matchConfig.Name = "ethUpstream";
         address = [ "10.31.245.2/24" ];
         gateway = [ "10.31.245.1" ];
       };
       "10-ethMgmt" = {
-        matchConfig.MACAddress = "BC:24:11:A3:38:4E";
+        matchConfig.Name = "ethMgmt";
         address = [ "10.20.25.2/24" ];
       };
     };
@@ -29,7 +44,7 @@
 
   networking.nat = {
     enable = true;
-    externalInterface = "ens18";
+    externalInterface = "ethUpstream";
     internalIPs = [ "10.20.25.0/24" ];
   };
 
@@ -38,7 +53,7 @@
     settings = {
       interfaces-config = {
         interfaces = [
-          "ens19"
+          "ethMgmt"
         ];
       };
       lease-database = {
@@ -50,31 +65,29 @@
       renew-timer = 1000;
       valid-lifetime = 4000;
       authoritative = true;
-      option-data = [
-        {
-          name = "domain-name-servers";
-          data = "9.9.9.9";
-        }
-        {
-          name = "routers";
-          data = "10.20.25.2";
-        }
-      ];
       shared-networks = [
         {
           name = "mgmtNet";
-          interface = "ens19";
+          interface = "ethMgmt";
+          option-data = [
+            {
+              name = "domain-name-servers";
+              data = "10.20.25.5";
+            }
+            {
+              name = "domain-search";
+              data = "noc.eh22.intern.";
+            }
+            {
+              name = "routers";
+              data = "10.20.25.2";
+            }
+          ];
           subnet4 = [
             {
               id = 300;
               subnet = "10.20.25.0/24";
               pools = [ { pool = "10.20.25.100 - 10.20.25.254"; } ];
-              reservations = [
-                {
-                  hw-address = "bc:24:11:c1:8a:a4";
-                  ip-address = "10.20.25.3";
-                }
-              ];
             }
           ];
         }