Producing Events/Messages to Kafka on a Secured Cluster
Prerequisite: Make sure that you have enabled access to the topic (via Ranger or native ACLs) for the user associated with the producer process. We recommend that you use Ranger to manage permissions. For more information, see the Apache Ranger User Guide for Kafka.
During the installation process, Ambari configures a series of Kafka client and producer settings, and creates a JAAS configuration file for the Kafka client. It is not necessary to modify these settings, but for more information about them see Appendix A, Kafka Configuration Options.
Note: Only the Kafka Java API is supported for Kerberos. Third-party clients are not supported.
To produce events/messages:
Specify the path to the JAAS configuration file as one of your JVM parameters:
-Djava.security.auth.login.config=/usr/hdp/current/kafka-broker/config/kafka_client_jaas.conf
For more information about the
kafka_client_jaas
file, see "JAAS Configuration File for the Kafka Client" in Kafka Configuration Options.kinit
with the principal's keytab.Launch
kafka-console-producer.sh
with the following configuration options. (Note: these settings are the same as in previous versions, except for the addition of--security-protocol SASL_PLAINTEXT
.)./bin/kafka-console-producer.sh --broker-list <hostname:port [,hostname:port, …]> --topic <topic-name> --security-protocol SASL_PLAINTEXT
For example:
./bin/kafka-console-producer.sh --broker-list c6401.ambari.apache.org:6667,c6402.ambari.apache.org:6667 --topic test_topic --security-protocol SASL_PLAINTEXT
Producer Code Example for a Kerberos-Enabled Cluster
The following example shows sample code for a producer in a Kerberos-enabled Kafka cluster.
Note that the SECURITY_PROTOCOL_CONFIG
property is set to
SASL_PLAINTEXT
.
package com.hortonworks.example.kafka.producer; import org.apache.kafka.clients.CommonClientConfigs; import org.apache.kafka.clients.producer.Callback; import org.apache.kafka.clients.producer.KafkaProducer; import org.apache.kafka.clients.producer.Producer; import org.apache.kafka.clients.producer.ProducerConfig; import org.apache.kafka.clients.producer.ProducerRecord; import org.apache.kafka.clients.producer.RecordMetadata; import java.util.Properties; import java.util.Random; public class BasicProducerExample { public static void main(String[] args){ Properties props = new Properties(); props.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "kafka.example.com:6667"); // specify the protocol for SSL Encryption props.put(CommonClientConfigs.SECURITY_PROTOCOL_CONFIG, "SASL_PLAINTEXT"); props.put(ProducerConfig.ACKS_CONFIG, "all"); props.put(ProducerConfig.RETRIES_CONFIG, 0); props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer"); props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, "org.apache.kafka.common.serialization.StringSerializer"); Producer<String, String> producer = new KafkaProducer<String, String>(props); TestCallback callback = new TestCallback(); Random rnd = new Random(); for (long i = 0; i < 100 ; i++) { ProducerRecord<String, String> data = new ProducerRecord<String, String>( "test-topic", "key-" + i, "message-"+i ); producer.send(data, callback); } producer.close(); } private static class TestCallback implements Callback { @Override public void onCompletion(RecordMetadata recordMetadata, Exception e) { if (e != null) { System.out.println("Error while producing message to topic :" + recordMetadata); e.printStackTrace(); } else { String message = String.format("sent message to topic:%s partition:%s offset:%s", recordMetadata.topic(), recordMetadata.partition(), recordMetadata.offset()); System.out.println(message); } } } }
To run the example, issue the following command:
$ java -Djava.security.auth.login.config=/usr/hdp/current/kafka-broker/config/kafka_client_jaas.conf com.hortonworks.example.kafka.producer.BasicProducerExample
Troubleshooting
Issue: If you launch the producer from the command-line
interface without specifying the security-protocol
option, you will see the
following error:
2015-07-21 04:14:06,611] ERROR fetching topic metadata for topics [Set(test_topic)] from broker [ArrayBuffer(BrokerEndPoint(0,c6401.ambari.apache.org,6667), BrokerEndPoint(1,c6402.ambari.apache.org,6667))] failed (kafka.utils.CoreUtils$) kafka.common.KafkaException: fetching topic metadata for topics [Set(test_topic)] from broker [ArrayBuffer(BrokerEndPoint(0,c6401.ambari.apache.org,6667), BrokerEndPoint(1,c6402.ambari.apache.org,6667))] failed at kafka.client.ClientUtils$.fetchTopicMetadata(ClientUtils.scala:73) Caused by: java.io.EOFException: Received -1 when reading from channel, socket has likely been closed. at kafka.utils.CoreUtils$.read(CoreUtils.scala:193) at kafka.network.BoundedByteBufferReceive.readFrom(BoundedByteBufferReceive.scala:54)
Solution: Add --security-protocol
SASL_PLAINTEXT
to the kafka-console-producer.sh
runtime options.