%3|1538976114.812|FAIL|rdkafka#producer-1| [thrd:kafka-server:9092/bootstrap]: kafka-server:9092/0: Receive failed: Disconnected
%3|1538976114.812|ERROR|rdkafka#producer-1| [thrd:kafka-server:9092/bootstrap]: kafka-server:9092/0: Receive failed: Disconnected
%3|1538976114.812|ERROR|rdkafka#producer-1| [thrd:kafka-server:9092/bootstrap]: 1/1 brokers are down
原因：
Why am I seeing Receive failed: Disconnected?
If the remote peer, typically the broker (but could also be an active TCP gateway of some kind), closes the connection you'll see a log message like this:
%3|1500588440.537|FAIL|rdkafka#producer-1| 10.255.84.150:9092/1: Receive failed: Disconnected
There are a number of possible reasons, in order of how common they are:
- Broker's idle connection reaper closes the connection due to inactivity. This is controlled by the broker configuration property
connections.max.idle.msand defaults to 10 minutes. This is by far the most common reason for spontaneous disconnects. - The client sent an unsupported protocol request; see Broker version compatibility. This is considered a configuration error on the client. The broker should log an exception explaining why the connection was closed, see the broker logs.
- The client sent a malformed protocol request; this is an indication of a bug in the client. The broker should log an exception explaining why the connection was closed, see the broker logs.
- The broker is in an invalid state. The broker should log an exception explaining why the connection was closed, see the broker logs.
- TCP gateway/load-balancer/firewall session timeout. Try enabling TCP keep-alives on the client by setting
socket.keepalive.enable=true.
Since a TCP close can't signal why the remote peer closed the connection there is no way for the client to know what went wrong. If the disconnect logs are getting annoying and the admin deems they are caused by the idle connection reaper, the log.connection.close client configuration property can be set to false to silence all spontaneous disconnect logs.
NOTE: Whenever a connection is closed for whatever reason, librdkafka will automatically reconnect after reconnect.backoff.jitter.ms (default 500ms).
簡單的說，其中之一是服務器會kill掉10分鍾空閑的連接，librdkafka會在連接斷開后500毫秒內重連。所以，根本解決方法就是沒事每分鍾發個心跳信息。
參考：https://github.com/edenhill/librdkafka/wiki/FAQ#why-am-i-seeing-receive-failed-disconnected