diff --git a/mqtt/sec/docker-compose.yml b/mqtt/sec/docker-compose.yml
index bd7c020..8cdfb6a 100644
--- a/mqtt/sec/docker-compose.yml
+++ b/mqtt/sec/docker-compose.yml
@@ -9,7 +9,8 @@ services:
       MQTT_HOSTNAME: ${MQTT_HOSTNAME:-mqtt.local}
       MQTT_USER: ${MQTT_USER:-mqttuser}
       MQTT_TLS_PORT: ${MQTT_TLS_PORT:-8883}
-
+    dns:
+      - ${DNS_SERVER}
     volumes:
       - ${VOLUME_ROOT:-.}/config:/mosquitto/config
       - ${VOLUME_ROOT:-.}/data:/mosquitto/data