报错：Bootstrap broker basecoalmine:2181 (id: -1 rack: null) disconnected (org.apache.kafka.clients.NetworkClient)

报错背景：

新安装的单机版kafka启动消费者的时候报错！

报错现象：

[2020-05-19 22:08:04,053] WARN [Consumer clientId=consumer-console-consumer-36457-1, groupId=console-consumer-36457] Bootstrap broker basecoalmine:2181 (id: -1 rack: null) disconnected (org.apache.kafka.clients.NetworkClient)
[2020-05-19 22:08:04,990] WARN [Consumer clientId=consumer-console-consumer-36457-1, groupId=console-consumer-36457] Bootstrap broker basecoalmine:2181 (id: -1 rack: null) disconnected (org.apache.kafka.clients.NetworkClient)
[2020-05-19 22:08:06,086] WARN [Consumer clientId=consumer-console-consumer-36457-1, groupId=console-consumer-36457] Bootstrap broker basecoalmine:2181 (id: -1 rack: null) disconnected (org.apache.kafka.clients.NetworkClient)

报错原因：

端口号的问题，以前启动消费者的时候监听的端口是 2181，但是新版本的kafka对zookeeper的依赖没有那么强烈了，所以改成了自己的 9092。

kafka-console-consumer.sh --bootstrap-server basecoalmine:2181 --topic test --from-beginning

报错解决：

修改端口号

kafka-console-consumer.sh --bootstrap-server basecoalmine:9092 --topic test --from-beginning