diff --git a/application.properties b/application.properties
index a03b4d5..c35e625 100644
--- a/application.properties
+++ b/application.properties
@@ -8,4 +8,4 @@ spring.jpa.hibernate.ddl-auto=update
 #-
 spring.jackson.serialization.indent_output=true
 #-
-de.ph87.knx.mqtt.uri=tcp://10.0.0.50:1883
+de.ph87.knx.mqtt.uri=tcp://10.255.0.1:1883
diff --git a/pom.xml b/pom.xml
index 2e440a1..d3f6bf1 100644
--- a/pom.xml
+++ b/pom.xml
@@ -5,7 +5,7 @@
   <modelVersion>4.0.0</modelVersion>
 
   <groupId>de.ph87</groupId>
-  <artifactId>DataMulti</artifactId>
+  <artifactId>Data2025</artifactId>
   <version>1.0-SNAPSHOT</version>
 
   <properties>
@@ -61,4 +61,14 @@
     </dependency>
   </dependencies>
 
+  <build>
+    <finalName>Data2025</finalName>
+    <plugins>
+      <plugin>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-maven-plugin</artifactId>
+      </plugin>
+    </plugins>
+  </build>
+
 </project>
\ No newline at end of file
diff --git a/src/main/java/de/ph87/data/DemoConfig.java b/src/main/java/de/ph87/data/DemoConfig.java
new file mode 100644
index 0000000..6b3f851
--- /dev/null
+++ b/src/main/java/de/ph87/data/DemoConfig.java
@@ -0,0 +1,14 @@
+package de.ph87.data;
+
+import lombok.Data;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.stereotype.Component;
+
+@Data
+@Component
+@ConfigurationProperties(prefix = "de.ph87.data.demo")
+public class DemoConfig {
+
+  private boolean enabled = false;
+
+}
diff --git a/src/main/java/de/ph87/data/DemoService.java b/src/main/java/de/ph87/data/DemoService.java
index 6a8f7d3..c32a415 100644
--- a/src/main/java/de/ph87/data/DemoService.java
+++ b/src/main/java/de/ph87/data/DemoService.java
@@ -39,9 +39,14 @@ public class DemoService {
 
   private final GraphRepository graphRepository;
 
+  private final DemoConfig demoConfig;
+
   @Transactional
   @EventListener(ApplicationReadyEvent.class)
   public void init() {
+    if (!demoConfig.isEnabled()) {
+      return;
+    }
     topics();
   }
 
diff --git a/src/main/java/de/ph87/data/mqtt/MqttConfig.java b/src/main/java/de/ph87/data/mqtt/MqttConfig.java
new file mode 100644
index 0000000..bd6d74c
--- /dev/null
+++ b/src/main/java/de/ph87/data/mqtt/MqttConfig.java
@@ -0,0 +1,18 @@
+package de.ph87.data.mqtt;
+
+import lombok.Data;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.stereotype.Component;
+
+@Data
+@Component
+@ConfigurationProperties(prefix = "de.ph87.data.mqtt")
+public class MqttConfig {
+
+  private String clientId;
+
+  private String uri;
+
+  private String topic = "#";
+
+}
diff --git a/src/main/java/de/ph87/data/mqtt/MqttService.java b/src/main/java/de/ph87/data/mqtt/MqttService.java
index 85193b5..c7ff5e7 100644
--- a/src/main/java/de/ph87/data/mqtt/MqttService.java
+++ b/src/main/java/de/ph87/data/mqtt/MqttService.java
@@ -6,11 +6,15 @@ import jakarta.annotation.PreDestroy;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.eclipse.paho.client.mqttv3.MqttClient;
+import org.eclipse.paho.client.mqttv3.MqttClientPersistence;
 import org.eclipse.paho.client.mqttv3.MqttConnectOptions;
 import org.eclipse.paho.client.mqttv3.MqttException;
 import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence;
+import org.eclipse.paho.client.mqttv3.persist.MqttDefaultFilePersistence;
 import org.springframework.stereotype.Service;
 
+import java.util.UUID;
+
 @Slf4j
 @Service
 @RequiredArgsConstructor
@@ -20,6 +24,8 @@ public class MqttService {
 
   private final Object lock = new Object();
 
+  private final MqttConfig config;
+
   private boolean stop = false;
 
   @PostConstruct
@@ -50,15 +56,18 @@ public class MqttService {
   private void connectOnce() throws InterruptedException {
     MqttClient client = null;
     try {
-      log.info("MQTT connecting...");
-      client = new MqttClient("tcp://10.0.0.50:1883", "DataDynamic", new MemoryPersistence());
+      final boolean cleanSession = config.getClientId() == null || config.getClientId().isEmpty();
+      final String clientId = cleanSession ? "Data2025-TMP-" + UUID.randomUUID() : config.getClientId();
+      final MqttClientPersistence persistence = cleanSession ? new MemoryPersistence() : new MqttDefaultFilePersistence();
+      log.info("MQTT connecting {} as {}{}...", config.getUri(), clientId, cleanSession ? " (CLEAN SESSION)" : "");
+      client = new MqttClient(config.getUri(), clientId, persistence);
       final MqttConnectOptions options = new MqttConnectOptions();
       options.setAutomaticReconnect(false);
-      options.setCleanSession(true);
+      options.setCleanSession(cleanSession);
       options.setConnectionTimeout(5);
       options.setKeepAliveInterval(2);
       client.connect(options);
-      client.subscribe("#", (topic, message) -> topicReceiver.receive(new MqttInbound(topic, new String(message.getPayload()))));
+      client.subscribe(config.getTopic(), 2, (topic, message) -> topicReceiver.receive(new MqttInbound(topic, new String(message.getPayload()))));
       log.info("MQTT connected.");
       synchronized (lock) {
         while (!stop && client.isConnected()) {
@@ -69,10 +78,13 @@ public class MqttService {
         }
       }
     } catch (MqttException e) {
-      log.error("MQTT connection error: {}", e.getMessage());
+      log.error("MQTT error.", e);
       synchronized (lock) {
         lock.wait(3000);
       }
+    } catch (Exception e) {
+      log.error("Unexpected error connecting MQTT.", e);
+      System.exit(1);
     } finally {
       if (client != null && client.isConnected()) {
         log.info("MQTT disconnecting...");