apache-kafka - Kafka 架构注册表错误 : Failed to write Noop record to kafka store

Question

我正在尝试启动 kafka 模式注册表，但出现以下错误:无法将 Noop 记录写入 kafka 存储。堆栈跟踪如下。我检查了与动物园管理员、卡夫卡经纪人的连接——一切都很好。我可以向 kafka 发布消息。我试图删除 _schema 主题，甚至重新安装 kafka，但这个问题仍然发生。昨天一切正常，但今天，在重新启动我的流浪盒子后，出现了这个问题。有什么我可以做的吗？谢谢

[2015-11-19 19:12:25,904] INFO SchemaRegistryConfig values: 
master.eligibility = true
port = 8081
kafkastore.timeout.ms = 500
kafkastore.init.timeout.ms = 60000
debug = false
kafkastore.zk.session.timeout.ms = 30000
request.logger.name = io.confluent.rest-utils.requests
metrics.sample.window.ms = 30000
schema.registry.zk.namespace = schema_registry
kafkastore.topic = _schemas
avro.compatibility.level = none
shutdown.graceful.ms = 1000
response.mediatype.preferred = [application/vnd.schemaregistry.v1+json, application/vnd.schemaregistry+json, application/json]
metrics.jmx.prefix = kafka.schema.registry
host.name = 12bac2a9529f
metric.reporters = []
kafkastore.commit.interval.ms = -1
kafkastore.connection.url = master.mesos:2181
metrics.num.samples = 2
response.mediatype.default = application/vnd.schemaregistry.v1+json
kafkastore.topic.replication.factor = 3
(io.confluent.kafka.schemaregistry.rest.SchemaRegistryConfig:135)

[2015-11-19 19:12:25,904] INFO SchemaRegistryConfig values: 
master.eligibility = true
port = 8081
kafkastore.timeout.ms = 500
kafkastore.init.timeout.ms = 60000
debug = false
kafkastore.zk.session.timeout.ms = 30000
request.logger.name = io.confluent.rest-utils.requests
metrics.sample.window.ms = 30000
schema.registry.zk.namespace = schema_registry
kafkastore.topic = _schemas
avro.compatibility.level = none
shutdown.graceful.ms = 1000
response.mediatype.preferred = [application/vnd.schemaregistry.v1+json, application/vnd.schemaregistry+json, application/json]
metrics.jmx.prefix = kafka.schema.registry
host.name = 12bac2a9529f
metric.reporters = []
kafkastore.commit.interval.ms = -1
kafkastore.connection.url = master.mesos:2181
metrics.num.samples = 2
response.mediatype.default = application/vnd.schemaregistry.v1+json
kafkastore.topic.replication.factor = 3
(io.confluent.kafka.schemaregistry.rest.SchemaRegistryConfig:135)
[2015-11-19 19:12:26,535] INFO Initialized the consumer offset to -1        (io.confluent.kafka.schemaregistry.storage.KafkaStoreReaderThread:87)
[2015-11-19 19:12:27,167] WARN Creating the schema topic _schemas using a replication factor of 1, which is less than the desired one of 3. If this is a production environment, it's crucial to add more brokers and increase the replication factor of the topic.   (io.confluent.kafka.schemaregistry.storage.KafkaStore:172)
[2015-11-19 19:12:27,262] INFO [kafka-store-reader-thread-_schemas], Starting  (io.confluent.kafka.schemaregistry.storage.KafkaStoreReaderThread:68)
[2015-11-19 19:13:27,350] ERROR Error starting the schema registry (io.confluent.kafka.schemaregistry.rest.SchemaRegistryRestApplication:57)
io.confluent.kafka.schemaregistry.exceptions.SchemaRegistryInitializationException: Error initializing kafka store while initializing schema registry
at   io.confluent.kafka.schemaregistry.storage.KafkaSchemaRegistry.init(KafkaSchemaRegistry.java:164)
at io.confluent.kafka.schemaregistry.rest.SchemaRegistryRestApplication.setupResources(SchemaRegistryRestApplication.java:55)
at io.confluent.kafka.schemaregistry.rest.SchemaRegistryRestApplication.setupResources(SchemaRegistryRestApplication.java:37)
at io.confluent.rest.Application.createServer(Application.java:104)
at io.confluent.kafka.schemaregistry.rest.Main.main(Main.java:42)
Caused by: io.confluent.kafka.schemaregistry.storage.exceptions.StoreInitializationException: io.confluent.kafka.schemaregistry.storage.exceptions.StoreException: Failed to write Noop record to kafka store.
at io.confluent.kafka.schemaregistry.storage.KafkaStore.init(KafkaStore.java:151)
at io.confluent.kafka.schemaregistry.storage.KafkaSchemaRegistry.init(KafkaSchemaRegistry.java:162)
... 4 more
Caused by: io.confluent.kafka.schemaregistry.storage.exceptions.StoreException: Failed to write Noop record to kafka store.
at io.confluent.kafka.schemaregistry.storage.KafkaStore.getLatestOffset(KafkaStore.java:363)
at io.confluent.kafka.schemaregistry.storage.KafkaStore.waitUntilKafkaReaderReachesLastOffset(KafkaStore.java:220)
at io.confluent.kafka.schemaregistry.storage.KafkaStore.init(KafkaStore.java:149)
... 5 more

Answer 1

错误消息具有误导性，正如其他开发人员在其他帖子中所推荐的那样，我建议如下。

1) 确保 Zookeeper 正在运行。 (检查日志文件以及进程是否处于事件状态)

2)确保你的kafka集群中的各个节点可以相互通信(telnet到主机和端口)

3) 如果 1 和 2 都很好，那么 我不推荐 创建另一个主题(如某些人在其他帖子上推荐的 _schema2)并使用新主题更新 schemaregistry 配置文件 kafkastore.topic。
反而
3.1) 停止进程(zookeeper、kafka 服务器)
3.2)清理zookeeper数据目录下的数据
3.3)重启zookeeper，kafka服务器，最后是schemaregistry服务(它应该可以工作!)

P.S:如果您确实尝试创建另一个主题，那么当您尝试使用 kafka 主题中的数据时，您可能会卡住。(发生在我身上，我花了几个小时才弄明白这一点!!!)。