diff --git a/.env.example b/.env.example
index 07dd09db874d1745502c601eec7167ba6ed9c63c..b7fe1737c86f1a88c714c5fe23c3e24da0dceaef 100644
--- a/.env.example
+++ b/.env.example
@@ -1,4 +1,5 @@
 MQTT_SERVER_ENABLED=false
+MQTT_LISTEN=0.0.0.0:1883 # only required for MQTT server
 MQTT_HOST=1.2.3.4
 MQTT_PORT=1883
 MQTT_USERNAME=mqtt