Kafka【问题 03】Connection to node -1 (/IP:9092) could not be established. Broker may not be available.

1.报错详情

此问题仅出现在云服务器上，非云服务器未出现过一下报错：

15:50:26.736 [kafka-producer-network-thread | producer-1] 
WARN  o.a.k.c.NetworkClient - [processDisconnection,782] - [Producer clientId=producer-1] 
Connection to node -1 (/172.81.205.216:9092) could not be established. 
Broker may not be available.

2.配置问题

非云服务器：

# 报错时仅配置了
listeners=PLAINTEXT://IP:9092

云服务器：

# 处理后
listeners=PLAINTEXT://云服务器IP:9092
advertised.listeners=PLAINTEXT://云服务器外网IP:9092

3.总结

• 云服务器有两个IP，监听IP为云服务器IP，而advertised监听IP为云服务器的外网IP。