diff --git a/echo2_config.cc b/echo2_config.cc
index cb3b56ee0..a956c7283 100644
--- a/echo2_config.cc
+++ b/echo2_config.cc
@@ -27,7 +27,7 @@ class Echo2ConfigFactory : public NamedNetworkFilterConfigFactory {
 
   std::string name() const override { return "echo2"; }
 
-  bool isTerminalFilter() override { return true; }
+  bool isTerminalFilterByProto(const Protobuf::Message&, FactoryContext&) override { return true; }
 };
 
 /**