Update README.md

Author: rama-nallamilli

README.md

@@ -18,8 +18,8 @@ docker-compose up
 ### Sending Kafka messages
 In order for the Kafka broker to expose JMX topic metrics you must send some messages to the topics.
 ```
-cat kafka-messages | docker run -i -a stdin wurstmeister/kafka /opt/kafka_2.11-0.10.0.1/bin/kafka-console-producer.sh --broker-list 192.168.99.100:9092 --topic customer
-cat kafka-messages | docker run -i -a stdin wurstmeister/kafka /opt/kafka_2.11-0.10.0.1/bin/kafka-console-producer.sh --broker-list 192.168.99.100:9092 --topic audit
+cat kafka-messages | docker run -i -a stdin wurstmeister/kafka /opt/kafka_2.11-0.10.0.1/bin/kafka-console-producer.sh --broker-list $DOCKER_HOST_IP:9092 --topic customer
+cat kafka-messages | docker run -i -a stdin wurstmeister/kafka /opt/kafka_2.11-0.10.0.1/bin/kafka-console-producer.sh --broker-list $DOCKER_HOST_IP:9092 --topic audit
 ```
 
 ### Viewing Prometheus Metrics