消费者有时不工作，有时却不工作，无法解决问题。
spring boot - 1.5.21.release
kafka client - 0.11.0.0
kafka servers - IBM event stream service on cloud.
应用属性：
#Producer
spring.kafka.template.default-topic=distitopic
spring.kafka.producer.client-id=event-streams-kafka
spring.kafka.producer.key-serializer=org.apache.kafka.common.serialization.StringSerializer
spring.kafka.producer.value-serializer=org.apache.kafka.common.serialization.StringSerializer
#Consumer
tier2.disti.search.topic=distitopic
spring.kafka.consumer.enable-auto-commit=false
spring.kafka.consumer.group-id=distigroup
spring.kafka.consumer.auto-offset-reset=latest
spring.kafka.consumer.key-deserializer=org.apache.kafka.common.serialization.StringDeserializer
spring.kafka.consumer.value-deserializer=org.apache.kafka.common.serialization.StringDeserializer
在我的休息控制器中，我有这个方法
@KafkaListener(topics = "${tier2.disti.search.topic}")
public void listen(ConsumerRecord<String, String> cr) throws Exception {
在 WebSphere Application Server 的系统输出日志中，我经常看到这些消息
[7/8/19 13:17:04:662 GMT] 00000347 SystemOut O 2019-07-08 13:17:04.662 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 5 could not be established. Broker may not be available.
[7/8/19 13:17:24:246 GMT] 0000033e SystemOut O 2019-07-08 13:17:24.246 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:19:12:022 GMT] 00000347 SystemOut O 2019-07-08 13:19:12.022 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 8 could not be established. Broker may not be available.
[7/8/19 13:19:32:630 GMT] 0000033e SystemOut O 2019-07-08 13:19:32.630 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:21:19:510 GMT] 00000347 SystemOut O 2019-07-08 13:21:19.510 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 4 could not be established. Broker may not be available.
[7/8/19 13:21:41:014 GMT] 0000033e SystemOut O 2019-07-08 13:21:41.014 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:23:26:870 GMT] 00000347 SystemOut O 2019-07-08 13:23:26.870 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 7 could not be established. Broker may not be available.
[7/8/19 13:23:49:526 GMT] 0000033e SystemOut O 2019-07-08 13:23:49.526 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:25:34:230 GMT] 00000347 SystemOut O 2019-07-08 13:25:34.230 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 5 could not be established. Broker may not be available.
[7/8/19 13:25:58:038 GMT] 0000033e SystemOut O 2019-07-08 13:25:58.038 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:27:41:590 GMT] 00000347 SystemOut O 2019-07-08 13:27:41.590 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 7 could not be established. Broker may not be available.
[7/8/19 13:28:06:550 GMT] 0000033e SystemOut O 2019-07-08 13:28:06.550 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:29:48:950 GMT] 00000347 SystemOut O 2019-07-08 13:29:48.950 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 4 could not be established. Broker may not be available.
[7/8/19 13:30:14:934 GMT] 0000033e SystemOut O 2019-07-08 13:30:14.934 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:32:23:062 GMT] 0000033e SystemOut O 2019-07-08 13:32:23.062 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:34:31:446 GMT] 0000033e SystemOut O 2019-07-08 13:34:31.446 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:36:39:702 GMT] 0000033e SystemOut O 2019-07-08 13:36:39.702 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:38:47:958 GMT] 0000033e SystemOut O 2019-07-08 13:38:47.958 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:40:56:086 GMT] 0000033e SystemOut O 2019-07-08 13:40:56.086 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:41:26:678 GMT] 00000347 SystemOut O 2019-07-08 13:41:26.678 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 6 could not be established. Broker may not be available.
[7/8/19 13:43:04:342 GMT] 0000033e SystemOut O 2019-07-08 13:43:04.342 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:45:12:854 GMT] 0000033e SystemOut O 2019-07-08 13:45:12.854 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:47:21:110 GMT] 0000033e SystemOut O 2019-07-08 13:47:21.110 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:48:34:070 GMT] 00000347 SystemOut O 2019-07-08 13:48:34.070 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 4 could not be established. Broker may not be available.
[7/8/19 13:49:29:622 GMT] 0000033e SystemOut O 2019-07-08 13:49:29.622 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:50:41:558 GMT] 00000347 SystemOut O 2019-07-08 13:50:41.558 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 6 could not be established. Broker may not be available.
[7/8/19 13:51:38:006 GMT] 0000033e SystemOut O 2019-07-08 13:51:38.006 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:52:48:918 GMT] 00000347 SystemOut O 2019-07-08 13:52:48.918 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 7 could not be established. Broker may not be available.
[7/8/19 13:53:46:518 GMT] 0000033e SystemOut O 2019-07-08 13:53:46.518 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:55:55:030 GMT] 0000033e SystemOut O 2019-07-08 13:55:55.030 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:58:03:670 GMT] 0000033e SystemOut O 2019-07-08 13:58:03.670 WARN 32021 --- [ntainer#0-0-C-1] org.apache.kafka.clients.NetworkClient : [Consumer clientId=consumer-1, groupId=distigroup] Connection to node -5 could not be established. Broker may not be available.
[7/8/19 13:59:56:310 GMT] 00000347 SystemOut O 2019-07-08 13:59:56.310 WARN 32021 --- [t-streams-kafka] org.apache.kafka.clients.NetworkClient : [Producer clientId=event-streams-kafka] Connection to node 8 could not be established. Broker may not be available.