diff --git a/bin/znn_controller.dart b/bin/znn_controller.dart
index 065c550..e0a58e2 100644
--- a/bin/znn_controller.dart
+++ b/bin/znn_controller.dart
@@ -378,6 +378,8 @@ void _printServiceStatus() {
 bool _verifyProducerConfig(Map<dynamic, dynamic> config) {
   if (!config.containsKey('Producer')) {
     return false;
+  } else if config['Producer'] == null {
+      return false;
   }
   if (!config['Producer'].containsKey('Index') ||
       !config['Producer'].containsKey('KeyFilePath') ||