java - 无法连接到kafka服务器

Question

我尝试使用带有端口 9092 的 0.9.0 版本的 Kafka。 如果我使用 telnet，我成功连接到这个地址， 但是我无法使用 Java API 连接到 Kafka 服务器

这是我的 Java 示例，完全使用官方提供的文档:

Properties props = new Properties();
props.put("bootstrap.servers", "192.168.174.128:9092");
props.put("acks", "all");
props.put("retries", 0);
props.put("batch.size", 16384);
props.put("linger.ms", 1);
props.put("buffer.memory", 33554432);
props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");

Producer<String, String> producer = new KafkaProducer(props);
for(int i = 1; i < 10; i++) ｛
  producer.send(new ProducerRecord<String, String>("test", Integer.toString(i), Integer.toString(i)));

｝

producer.close();

我使用 vmware 虚拟机构建我的 Kafka 服务器和 Zookeeper。我的虚拟机IP地址是192.168.174.128。我使用 Kafka 客户端成功创建和使用了消息。

这是异常的完整堆栈

2016-01-03 09:44:38.049 [kafka-producer-network-thread | producer-1] DEBUG [] [] Selector - Connection with localhost/127.0.0.1 disconnected
java.net.ConnectException: Connection refused: no further information
    at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method) ~[na:1.7.0_51]
    at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:739) ~[na:1.7.0_51]
    at org.apache.kafka.common.network.PlaintextTransportLayer.finishConnect(PlaintextTransportLayer.java:54) ~[kafka-clients-0.9.0.0.jar:na]
    at org.apache.kafka.common.network.KafkaChannel.finishConnect(KafkaChannel.java:79) ~[kafka-clients-0.9.0.0.jar:na]
    at org.apache.kafka.common.network.Selector.poll(Selector.java:274) ~[kafka-clients-0.9.0.0.jar:na]
    at org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:270) [kafka-clients-0.9.0.0.jar:na]
    at org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:216) [kafka-clients-0.9.0.0.jar:na]
    at org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:141) [kafka-clients-0.9.0.0.jar:na]
    at java.lang.Thread.run(Thread.java:744) [na:1.7.0_51]
2016-01-03 09:44:38.049 [kafka-producer-network-thread | producer-1] DEBUG [] [] NetworkClient - Node 0 disconnected.
2016-01-03 09:44:38.078 [kafka-producer-network-thread | producer-1] DEBUG [] [] NetworkClient - No node found. Trying previously-seen node with ID 0
2016-01-03 09:44:38.078 [kafka-producer-network-thread | producer-1] DEBUG [] [] NetworkClient - Give up sending metadata request since no node is available
2016-01-03 09:44:38.099 [kafka-producer-network-thread | producer-1] DEBUG [] [] NetworkClient - Initiating connection to node 0 at localhost:9092.
2016-01-03 09:44:38.681 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name connections-closed:client-id-producer-1
2016-01-03 09:44:38.681 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name connections-created:client-id-producer-1
2016-01-03 09:44:38.681 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name bytes-sent-received:client-id-producer-1
2016-01-03 09:44:38.681 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name bytes-received:client-id-producer-1
2016-01-03 09:44:38.682 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name bytes-sent:client-id-producer-1
2016-01-03 09:44:38.682 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name select-time:client-id-producer-1
2016-01-03 09:44:38.682 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name io-time:client-id-producer-1
2016-01-03 09:44:38.682 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name node--1.bytes-sent
2016-01-03 09:44:38.683 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name node--1.bytes-received
2016-01-03 09:44:38.683 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name node--1.latency
2016-01-03 09:44:38.683 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name node-0.bytes-sent
2016-01-03 09:44:38.683 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name node-0.bytes-received
2016-01-03 09:44:38.683 [kafka-producer-network-thread | producer-1] DEBUG [] [] Metrics - Removed sensor with name node-0.latency
2016-01-03 09:44:38.683 [kafka-producer-network-thread | producer-1] DEBUG [] [] Sender - Shutdown of Kafka producer I/O thread has completed.
2016-01-03 09:44:38.683 [main] DEBUG [] [] KafkaProducer - The Kafka producer has closed.

Answer 1

我遇到了这个问题。要解决此问题，您应该取消注释 server.properties 文件中的以下配置，并用您的 zookeeper 的 IP 填充它。

advertised.host.name = zookeeper IP

正如kafka文档所说，这个配置是

Hostname to publish to ZooKeeper for clients to use

因为在新的 kafka consumer (0.9) 中，consumer 向 broker 询问 zookeeper IP。