diff --git a/hosts/containers/freifunk/default.nix b/hosts/containers/freifunk/default.nix
index 1a468b0f..5b85928f 100644
--- a/hosts/containers/freifunk/default.nix
+++ b/hosts/containers/freifunk/default.nix
@@ -255,7 +255,10 @@ in {
           import all;
         };
         area 0 {
-          interface "core" {};
+          interface "core" {
+            authentication cryptographic;
+            password "${pkgs.zentralwerk-ospf-message-digest-key}";
+          };
         };
       }
 
diff --git a/hosts/containers/yggdrasil/default.nix b/hosts/containers/yggdrasil/default.nix
index 3b1a9060..228f7973 100644
--- a/hosts/containers/yggdrasil/default.nix
+++ b/hosts/containers/yggdrasil/default.nix
@@ -132,13 +132,11 @@ in {
 
       protocol ospf v3 ZW6 {
         area 0 {
-          networks {
-            fd23:42:c3d2:500::/56;
-            2a02:8106:208:5200::/56;
-            2a02:8106:211:e900::/56;
-          };
           stubnet 200::/7 {};
-          interface "core" {};
+          interface "core" {
+            authentication cryptographic;
+            password "${pkgs.zentralwerk-ospf-message-digest-key}";
+          };
         };
       }