Hi Alex,
which version of Flink are you running? There were some class loading
issues with Kafka recently. I would try it with the newest Flink
version. Otherwise ClassNotFoundException usually indicates that
something is wrong with your dependencies. Maybe you can share your
pom.xml with us.
Regards,
Timo
Am 02.04.18 um 13:32 schrieb Alexander Smirnov:
I see a lot of messages in flink log like below. What's the cause?
02 Apr 2018 04:09:13,554 ERROR
org.apache.kafka.clients.producer.internals.Sender - Uncaught error in
kafka producer I/O thread:
org.apache.kafka.common.KafkaException: Error registering mbean
kafka.producer:type=producer-node-metrics,client-id=producer-1,node-id=node-1
at
org.apache.kafka.common.metrics.JmxReporter.reregister(JmxReporter.java:163)
at
org.apache.kafka.common.metrics.JmxReporter.metricChange(JmxReporter.java:81)
at
org.apache.kafka.common.metrics.Metrics.registerMetric(Metrics.java:504)
at org.apache.kafka.common.metrics.Sensor.add(Sensor.java:255)
at org.apache.kafka.common.metrics.Sensor.add(Sensor.java:240)
at
org.apache.kafka.common.network.Selector$SelectorMetrics.maybeRegisterConnectionMetrics(Selector.java:811)
at
org.apache.kafka.common.network.Selector.pollSelectionKeys(Selector.java:353)
at
org.apache.kafka.common.network.Selector.poll(Selector.java:326)
at
org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:433)
at
org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:224)
at
org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:162)
at java.lang.Thread.run(Thread.java:748)
Caused by: javax.management.InstanceAlreadyExistsException:
kafka.producer:type=producer-node-metrics,client-id=producer-1,node-id=node-1
at
com.sun.jmx.mbeanserver.Repository.addMBean(Repository.java:437)
at
com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerWithRepository(DefaultMBeanServerInterceptor.java:1898)
at
com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerDynamicMBean(DefaultMBeanServerInterceptor.java:966)
at
com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerObject(DefaultMBeanServerInterceptor.java:900)
at
com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerMBean(DefaultMBeanServerInterceptor.java:324)
at
com.sun.jmx.mbeanserver.JmxMBeanServer.registerMBean(JmxMBeanServer.java:522)
at
org.apache.kafka.common.metrics.JmxReporter.reregister(JmxReporter.java:161)
... 11 more
02 Apr 2018 04:09:13,673 ERROR
org.apache.kafka.common.utils.KafkaThread - Uncaught exception in
kafka-producer-network-thread | producer-3:
java.lang.NoClassDefFoundError: org/apache/kafka/clients/NetworkClient$1
at
org.apache.kafka.clients.NetworkClient.processDisconnection(NetworkClient.java:583)
at
org.apache.kafka.clients.NetworkClient.handleDisconnections(NetworkClient.java:705)
at
org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:443)
at
org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:224)
at
org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:162)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.ClassNotFoundException:
org.apache.kafka.clients.NetworkClient$1
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at
org.apache.flink.runtime.execution.librarycache.FlinkUserCodeClassLoaders$ChildFirstClassLoader.loadClass(FlinkUserCodeClassLoaders.java:128)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 6 more
Thank you,
Alex
