The system on which my Kafka server is running has two NICs, one with a public IP (188.8.131.52) and the other with a private one (192.168.1.14). The private NIC is connected to a subnet composed of 7 machines in total (all with addresses 192.168.1.xxx). Kafka has been installed as a service using HDP and has been configured with zookeeper.connect=192.168.1.14:2181 and listeners=PLAINTEXT://192.168.1.14:6667. I have started a consumer on the system that hosts the kafka server using: [bin/kafka-console-consumer.sh --bootstrap-server 192.168.1.14:6667 --topic test --from-beginning].
When I start producers (using [bin/kafka-console-producer.sh --broker-list 192.168.1.14:6667 --topic test]) on any of the machines on the private subnet the messages are received normally by the consumer.
I would like to start producers on public systems and receive the messages by the consumer running on the kafka server. I believed that this could be achieved by IP masquerading and by forwarding all external requests to 184.108.40.206:15501 (I have chosen 15501 to receive kafka messages) to 192.168.1.14:6667. To that extend I setup this port forwarding rule on firewalld: [port=15501:proto=tcp:toport=6670:toaddr=192.168.1.14].
However, this doesn’t seem to work since when I start a producer on an external system with [bin/kafka-console-producer.sh --broker-list 220.127.116.11:15501 --topic] the messages cannot be received by the consumer.
I have tried different kafka config settings for listeners and advertised.listeners but none of them worked. Any help will be greatly appreciated.
advertized listeners needs to be configured for your Kafka brokers but the consumer also has to use the public subnet.
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