Kafka Producer Timeout Issue connecting to message-hub on Bluemix

Question

I am trying to connect to IBM Bluemix message-hub and produce a message using java following the example

https://github.com/ibm-messaging/message-hub-samples/tree/master/java/message-hub-kafka-ssl

producer.properties

key.serializer=org.apache.kafka.common.serialization.ByteArraySerializer
value.serializer=org.apache.kafka.common.serialization.ByteArraySerializer
acks=-1
security.protocol=SASL_SSL
sasl.mechanism=PLAIN
ssl.protocol=TLSv1.2
ssl.enabled.protocols=TLSv1.2
ssl.truststore.password=changeit
ssl.truststore.type=JKS
ssl.endpoint.identification.algorithm=HTTPS
ssl.truststore.location=/Library/Java/JavaVirtualMachines/jdk1.8.0_66.jdk/Contents/Home/jre/lib/security/cacerts

jaas.conf.template

KafkaClient {
    com.ibm.messagehub.login.MessageHubLoginModule required
    serviceName="kafka"
    user="$USERNAME"
    password="$PASSWORD";
};

Producer.java snippet

ProducerRecord<byte[], byte[]> record = new ProducerRecord<byte[], byte[]>(
                "MyTopic",
                KEY.getBytes("UTF-8"),
                "MESSAGE".getBytes("UTF-8"));

        // Synchronously wait for a response from Message Hub / Kafka.
        RecordMetadata m = kafkaProducer.send(record).get();

The problem is , I am getting a timeout exception when I am trying to get the Future RecordMetadata

java.util.concurrent.ExecutionException: org.apache.kafka.common.errors.TimeoutException: Failed to update metadata after 60000 ms.
at org.apache.kafka.clients.producer.KafkaProducer$FutureFailure.<init>(KafkaProducer.java:730)
at org.apache.kafka.clients.producer.KafkaProducer.doSend(KafkaProducer.java:483)
at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:430)
at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:353)

Read an earlier post on the same topic

Timeout connecting to message-hub on Bluemix

And the possible reason mentioned was the topic was not created.I can see the topic in bluemix console and to verify, I called the rest service to fetch the list of topics before pushing the message

RESTRequest restApi = new RESTRequest(getRestHost(),getApiKey());

String topics = restApi.get("/admin/topics", false);

logger.info("Topics present in the system: " + topics);

It returns the topic where I am trying to push a message and yet I am getting the timeout error.

Can someone please help me in debugging the issue

UPDATE

Based on comments , I enabled debug logs for kafka, and here is the sequence of logs

2016-11-23 08:48:20.906 DEBUG 72885 --- [sage-hub-sample]    org.apache.kafka.clients.NetworkClient   : Initialize connection to node -5 for sending metadata request
2016-11-23 08:48:20.906 DEBUG 72885 --- [sage-hub-sample] org.apache.kafka.clients.NetworkClient   : Initiating connection to node -5 at kafka05-prod01.messagehub.services.us-south.bluemix.net:9093.
2016-11-23 08:48:20.914 DEBUG 72885 --- [sage-hub-sample] o.a.k.c.s.a.SaslClientAuthenticator      : Set SASL client state to SEND_HANDSHAKE_REQUEST
2016-11-23 08:48:20.915 DEBUG 72885 --- [sage-hub-sample] o.a.k.c.s.a.SaslClientAuthenticator      : Creating SaslClient: client=messagehub/ignorehost@messagehub.ibm.com;service=kafka;serviceHostname=kafka05-prod01.messagehub.services.us-south.bluemix.net;mechs=[PLAIN]
2016-11-23 08:48:20.979 DEBUG 72885 --- [sage-hub-sample] org.apache.kafka.common.metrics.Metrics  : Added sensor with name node--5.bytes-sent
2016-11-23 08:48:20.980 DEBUG 72885 --- [sage-hub-sample] org.apache.kafka.common.metrics.Metrics  : Added sensor with name node--5.bytes-received
2016-11-23 08:48:20.980 DEBUG 72885 --- [sage-hub-sample] org.apache.kafka.common.metrics.Metrics  : Added sensor with name node--5.latency
2016-11-23 08:48:20.982 DEBUG 72885 --- [sage-hub-sample] org.apache.kafka.clients.NetworkClient   : Completed connection to node -5
2016-11-23 08:48:21.080 DEBUG 72885 --- [sage-hub-sample] o.a.k.c.s.a.SaslClientAuthenticator      : Set SASL client state to RECEIVE_HANDSHAKE_RESPONSE

2016-11-23 08:48:21.264 DEBUG 72885 --- [sage-hub-sample] o.a.k.c.s.a.SaslClientAuthenticator      : Set SASL client state to INITIAL
2016-11-23 08:48:21.265 DEBUG 72885 --- [sage-hub-sample] o.a.k.c.s.a.SaslClientAuthenticator      : Set SASL client state to INTERMEDIATE
2016-11-23 08:48:21.284 DEBUG 72885 --- [sage-hub-sample]  o.apache.kafka.common.network.Selector   : Connection with kafka05-prod01.messagehub.services.us-south.bluemix.net/23.246.202.55 disconnected

java.io.EOFException: null
at org.apache.kafka.common.network.SslTransportLayer.read(SslTransportLayer.java:488)
at org.apache.kafka.common.network.NetworkReceive.readFromReadableChannel(NetworkReceive.java:81)
at org.apache.kafka.common.network.NetworkReceive.readFrom(NetworkReceive.java:71)
at org.apache.kafka.common.security.authenticator.SaslClientAuthenticator.receiveResponseOrToken(SaslClientAuthenticator.java:239)
at org.apache.kafka.common.security.authenticator.SaslClientAuthenticator.authenticate(SaslClientAuthenticator.java:182)
at org.apache.kafka.common.network.KafkaChannel.prepare(KafkaChannel.java:64)
at org.apache.kafka.common.network.Selector.pollSelectionKeys(Selector.java:318)
at org.apache.kafka.common.network.Selector.poll(Selector.java:283)
at org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:260)
at org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:229)
at org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:134)
at java.lang.Thread.run(Thread.java:745)

All the above are logged for any of the 5 brokers. Also these are all debug statements so I am not sure whether they are errors.

-Tatha

Answer 1

I can see a couple of issues with your JAAS file:

• The sample you're referring to is using Kafka 0.10.0.X so you should not use the old Message Hub login module for Kafka 0.9. So replace "com.ibm.messagehub.login.MessageHubLoginModule" by "org.apache.kafka.common.security.plain.PlainLoginModule"

• The field for the user name is called "username" and not "user". It should be username="$USERNAME"

Answer 2

please enable log4j DEBUG level and the Kafka client trace may help identify any connectivity issues. Try change the last line to log4j.logger.org.apache.kafka=DEBUG in the log4j.properties file, rebuild and take a look at the verbose output. Feel free to repost that.