Kafka錯誤“Network is unreachable”和“larger than available brokers”

确定Kafka安裝和啟動正确，ZooKeeper可以查到所有的Brokers，但執行：

kafka-topics.sh --create --zookeeper localhost:2181 --replication-factor 3 --partitions 1 --topic my-replicated-topic

遇到如下錯誤：

java.net.SocketException: Network is unreachable

        at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)

        at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:717)

        at org.apache.zookeeper.ClientCnxnSocketNIO.doTransport(ClientCnxnSocketNIO.java:361)

        at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1141)

Error while executing topic command : replication factor: 3 larger than available brokers: 0

[2017-06-26 17:25:18,037] ERROR org.apache.kafka.common.errors.InvalidReplicationFactorException: replication factor: 3 larger than available brokers: 0

這個問題可能是broker的配置檔案server.properties中的配置項zookeeper.connect指定了kafka的zookeeper的根目錄，如：

zookeeper.connect=192.168.31.32:2181,192.168.31.33:2181/kafka

這個時候，指令行參數“--zookeeper”的值也需要帶上根目錄，否則就會報這個錯誤，正确做法是：

kafka-topics.sh --create --zookeeper localhost:2181/kafka --replication-factor 3 --partitions 1 --topic my-replicated-topic