为什么在运行KRaft模式时控制器必须是本地主机

Question

在KRaft模式下，卡夫卡代理不会启动，除非控制器监听localhost。例如，下列任一项在我的膝上型计算机上都不起作用：

listeners=PLAINTEXT://10.0.0.48:9092,CONTROLLER://10.0.0.48:9093
listeners=PLAINTEXT://192.168.56.1:9092,CONTROLLER://192.168.56.1:9093
listeners=PLAINTEXT://localhost:9092,CONTROLLER://192.168.56.1:9093

如果在上述任一项中用localhost替换控制器IP地址，则kafka-server-start.sh将成功启动。

在失败场景中，我不断地获得以下日志：

[2022-10-27 15:06:19,885] WARN [BrokerToControllerChannelManager broker=1 name=heartbeat] Connection to node 1 (localhost/127.0.0.1:9093) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2022-10-27 15:06:19,885] INFO [BrokerToControllerChannelManager broker=1 name=heartbeat]: Recorded new controller, from now on will use broker localhost:9093 (id: 1 rack: null) (kafka.server.BrokerToControllerRequestThread)
[2022-10-27 15:06:19,935] INFO [BrokerToControllerChannelManager broker=1 name=heartbeat]: Recorded new controller, from now on will use broker localhost:9093 (id: 1 rack: null) (kafka.server.BrokerToControllerRequestThread)
[2022-10-27 15:06:19,936] INFO [BrokerToControllerChannelManager broker=1 name=heartbeat] Node 1 disconnected. (org.apache.kafka.clients.NetworkClient)

直到我得到以下错误并且kafka-server-start.sh退出：

[2022-10-27 15:06:22,804] ERROR Exiting Kafka due to fatal exception during startup. (kafka.Kafka$)
java.util.concurrent.CancellationException
    at java.base/java.util.concurrent.CompletableFuture.cancel(CompletableFuture.java:2468)
    at kafka.server.BrokerLifecycleManager$ShutdownEvent.run(BrokerLifecycleManager.scala:485)
    at org.apache.kafka.queue.KafkaEventQueue$EventHandler.run(KafkaEventQueue.java:174)
    at java.base/java.lang.Thread.run(Thread.java:832)

它似乎期望控制器是localhost。如果是这样，为什么？

Answer 1

我不得不更改controller.quorum.voters以匹配listeners：controller.quorum.voters=1@192.168.56.1:9093中的内容