diff --git a/nix/nixos-module/container/bird.nix b/nix/nixos-module/container/bird.nix
index 4068773..acac414 100644
--- a/nix/nixos-module/container/bird.nix
+++ b/nix/nixos-module/container/bird.nix
@@ -150,7 +150,12 @@ in
                       password "${config.site.net.${net}.ospf.secret}";
                     };
                   ''
-                  else ""
+                  else ''
+                    interface "${net}" {
+                      stub yes;
+                      cost 10;
+                    };
+                  ''
                 ) hostConf.interfaces
               )
           )}
@@ -260,7 +265,12 @@ in
                       password "${config.site.net.${net}.ospf.secret}";
                     };
                   ''
-                  else ""
+                  else ''
+                    interface "${net}" {
+                      stub yes;
+                      cost 10;
+                    };
+                  ''
                 ) hostConf.physicalInterfaces
               )
           )}