kafka发送数据报错： Error connecting to node xxxxx:9092 (id: 1 rack: null)java.net.UnknownHostExceptio

报错内容：

warn报错：

[kafka-producer-network-thread | producer-1] WARN org.apache.kafka.clients.NetworkClient – [Producer clientId=producer-1] Error connecting to node xxxxx:9092 (id: 1 rack: null)

java.net.UnknownHostException: xxxxx

   at java.base/java.net.InetAddress$CachedAddresses.get(InetAddress.java:797)

   at java.base/java.net.InetAddress.getAllByName0(InetAddress.java:1519)

   at java.base/java.net.InetAddress.getAllByName(InetAddress.java:1378)

   at java.base/java.net.InetAddress.getAllByName(InetAddress.java:1306)

   at org.apache.kafka.clients.DefaultHostResolver.resolve(DefaultHostResolver.java:27)

   at org.apache.kafka.clients.ClientUtils.resolve(ClientUtils.java:111)

   at org.apache.kafka.clients.ClusterConnectionStates$NodeConnectionState.currentAddress(ClusterConnectionStates.java:512)

   at org.apache.kafka.clients.ClusterConnectionStates$NodeConnectionState.access$200(ClusterConnectionStates.java:466)

   at org.apache.kafka.clients.ClusterConnectionStates.currentAddress(ClusterConnectionStates.java:172)

   at org.apache.kafka.clients.NetworkClient.initiateConnect(NetworkClient.java:985)

   at org.apache.kafka.clients.NetworkClient.ready(NetworkClient.java:311)

   at org.apache.kafka.clients.producer.internals.Sender.sendProducerData(Sender.java:353)

   at org.apache.kafka.clients.producer.internals.Sender.runOnce(Sender.java:326)

   at org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:242)

   at java.base/java.lang.Thread.run(Thread.java:829)

error日志：

[kafka-producer-network-thread | producer-1] ERROR org.apache.kafka.clients.producer.internals.Sender – [Producer clientId=producer-1] Uncaught error in kafka producer I/O thread:

java.lang.IllegalStateException: No entry found for connection 1

   at org.apache.kafka.clients.ClusterConnectionStates.nodeState(ClusterConnectionStates.java:330)

   at org.apache.kafka.clients.ClusterConnectionStates.disconnected(ClusterConnectionStates.java:134)

   at org.apache.kafka.clients.NetworkClient.initiateConnect(NetworkClient.java:921)

   at org.apache.kafka.clients.NetworkClient.access$700(NetworkClient.java:67)

   at org.apache.kafka.clients.NetworkClient$DefaultMetadataUpdater.maybeUpdate(NetworkClient.java:1086)

   at org.apache.kafka.clients.NetworkClient$DefaultMetadataUpdater.maybeUpdate(NetworkClient.java:971)

   at org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:533)

   at org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:309)

   at org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:233)

   at java.base/java.lang.Thread.run(Thread.java:829)

本质原因是kafka配置文件server.properites中默认监听hostname：

# Hostname and port the broker will advertise to producers and consumers. If not set,

# it uses the value for “listeners” if configured. Otherwise, it will use the value

# returned from java.net.InetAddress.getCanonicalHostName().

#advertised.listeners=PLAINTEXT://your.host.name:9092

#advertised.listeners=PLAINTEXT://192.34.12.12:9092

两种解决方案

1.修改kafka服务的配置文件，改为监听ip，将 advertised.listeners 中的your.host.name 改为服务器的IP地址即可：