Kafka Manager 无法连接到代理答案

【问题标题】：Kafka Manager not able to connect to brokersKafka Manager 无法连接到代理
【发布时间】：2018-10-18 00:54:11
【问题描述】：

我有 3 个代理（brker1、broker2 和 broker3），我的 kafka 管理器能够连接到 broker2，但无法连接到剩余的两个代理（broker1 和 broker3）。我也重新启动了kafka-manager、broker1 和broker3，但仍然没有连接到这两个代理。

注意：- kafka 在 3 个代理上运行

我从kafka-manage得到的这个日志

[error] k.m.a.c.BrokerViewCacheActor - Failed to get broker metrics for BrokerIdentity(3,broker3,9092,9999,false)
java.rmi.ConnectException: Connection refused to host: IP; nested exception is:
    java.net.ConnectException: Connection refused (Connection refused)
    at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:619) ~[na:1.8.0_121]
    at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:216) ~[na:1.8.0_121]
    at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:202) ~[na:1.8.0_121]
    at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:130) ~[na:1.8.0_121]
    at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(RemoteObjectInvocationHandler.java:227) ~[na:1.8.0_121]
    at java.rmi.server.RemoteObjectInvocationHandler.invoke(RemoteObjectInvocationHandler.java:179) ~[na:1.8.0_121]
    at com.sun.proxy.$Proxy6.newClient(Unknown Source) ~[na:na]
    at javax.management.remote.rmi.RMIConnector.getConnection(RMIConnector.java:2430) ~[na:1.8.0_121]
    at javax.management.remote.rmi.RMIConnector.connect(RMIConnector.java:308) ~[na:1.8.0_121]
    at javax.management.remote.JMXConnectorFactory.connect(JMXConnectorFactory.java:270) ~[na:1.8.0_121]
Caused by: java.net.ConnectException: Connection refused (Connection refused)
    at java.net.PlainSocketImpl.socketConnect(Native Method) ~[na:1.8.0_121]
    at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) ~[na:1.8.0_121]
    at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) ~[na:1.8.0_121]
    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) ~[na:1.8.0_121]
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[na:1.8.0_121]
    at java.net.Socket.connect(Socket.java:589) ~[na:1.8.0_121]
    at java.net.Socket.connect(Socket.java:538) ~[na:1.8.0_121]
    at java.net.Socket.<init>(Socket.java:434) ~[na:1.8.0_121]
    at java.net.Socket.<init>(Socket.java:211) ~[na:1.8.0_121]
    at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirectSocketFactory.java:40) ~[na:1.8.0_121]
[info] k.m.a.KafkaManagerActor - Updating internal state...

我正在使用kafka-manager-1.3.2.1

3 个代理（broker1、broker2 和 broker3）正在运行

这是我从 broker1 获取的日志（kafka-manager 无法连接到此代理）

[2018-05-08 07:10:11,217] INFO [GroupCoordinator 1]: Loading group metadata for topic-1 with generation 27 (kafka.coordinator.GroupCoordinator)
[2018-05-08 07:10:11,217] INFO [GroupCoordinator 1]: Loading group metadata for topic-2 with generation 3 (kafka.coordinator.GroupCoordinator)
[2018-05-08 07:10:11,217] INFO [Group Metadata Manager on Broker 1]: Finished loading offsets from [__consumer_offsets,2] in 28 milliseconds. (kafka.coordinator.GroupMetadataManager)
[2018-05-08 07:10:11,218] INFO [Group Metadata Manager on Broker 1]: Loading offsets and group metadata from [__consumer_offsets,16] (kafka.coordinator.GroupMetadataManager)
[2018-05-08 07:10:11,224] INFO [Group Metadata Manager on Broker 1]: Finished loading offsets from [__consumer_offsets,16] in 6 milliseconds. (kafka.coordinator.GroupMetadataManager)
[2018-05-08 07:17:53,774] INFO [Group Metadata Manager on Broker 1]: Removed 0 expired offsets in 4 milliseconds. (kafka.coordinator.GroupMetadataManager)

【问题讨论】：

标签： apache-kafka apache-kafka-connect

【解决方案1】：

“连接被拒绝”错误可能表明没有进程在侦听该端口，或者该计算机上的防火墙阻止了该端口。

在运行kafka-manager的机器上，可以nc broker3 9092和nc broker3 9999吗？如果这两个命令“挂起”，则意味着这不仅仅是 Kafka Manager 的问题。

我意识到这是一个老问题，我只是在寻找其他东西时偶然发现了它。

【讨论】：

【解决方案2】：

您似乎需要发布 JMX PORT/HOST 以便 Kafka-Manager 能够发现代理，这些代理由代理启动脚本中的以下参数控制。

Djava.rmi.server.hostname=${ip}
JMX_PORT=9997

更多详情请关注：https://github.com/yahoo/kafka-manager/issues/214

【讨论】：