Kafka-cassandra connector fails after confluent 3.3 upgrade - cassandra

Question

The Cassandra connector fails after confluent upgrade to 3.3.0. The version of Cassandra driver is 3.3. The stack is given below.
[2017-09-14 08:56:28,123] ERROR java.lang.reflect.InvocationTargetException
(com.cantiz.nucleus.kafka.connector.cassandra.CassandraSinkTask:72)
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at com.google.common.base.Throwables.propagate(Throwables.java:240)
at com.datastax.driver.core.NettyUtil.newEventLoopGroupInstance(NettyUtil.java:136)
at com.datastax.driver.core.NettyOptions.eventLoopGroup(NettyOptions.java:99)
at com.datastax.driver.core.Connection$Factory.<init>(Connection.java:774)
at com.datastax.driver.core.Cluster$Manager.init(Cluster.java:1446)
at com.datastax.driver.core.Cluster.init(Cluster.java:159)
at com.datastax.driver.core.Cluster.connectAsync(Cluster.java:330)
at com.datastax.driver.core.Cluster.connectAsync(Cluster.java:305)
at com.datastax.driver.core.Cluster.connect(Cluster.java:247)
at com.attinad.cantiz.iot.historian.cassandra.session.CassandraSessionManager.connect(CassandraSessionManager.java:33)
at com.cantiz.nucleus.kafka.connector.cassandra.CassandraSinkTask.start(CassandraSinkTask.java:61)
at org.apache.kafka.connect.runtime.WorkerSinkTask.initializeAndStart(WorkerSinkTask.java:232)
at org.apache.kafka.connect.runtime.WorkerSinkTask.execute(WorkerSinkTask.java:145)
at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:146)
at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:190)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at com.datastax.driver.core.NettyUtil.newEventLoopGroupInstance(NettyUtil.java:134)
... 18 more
Caused by: java.lang.NoClassDefFoundError: Could not initialize class io.netty.channel.epoll.EpollEventLoop
at io.netty.channel.epoll.EpollEventLoopGroup.newChild(EpollEventLoopGroup.java:71)
at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:64)
at io.netty.channel.MultithreadEventLoopGroup.<init>(MultithreadEventLoopGroup.java:50)
at io.netty.channel.epoll.EpollEventLoopGroup.<init>(EpollEventLoopGroup.java:56)
at io.netty.channel.epoll.EpollEventLoopGroup.<init>(EpollEventLoopGroup.java:48)
... 23 more
[2017-09-14 08:56:28,125] INFO Sink task WorkerSinkTask{id=cassandra-thing-event-desc-3} finished initialization and start (org.apache.kafka.connect.runtime.WorkerSinkTask:233)
[2017-09-14 08:56:28,123] ERROR java.lang.reflect.InvocationTargetException (com.cantiz.nucleus.kafka.connector.cassandra.CassandraSinkTask:72)
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
I have tried by updating the guava and io.netty dependencies, but it doesn't resolved the issue.

Answer 1

The issue was due to the Cassandra driver 3.3.0 uses Netty 4.0.47.Final instead of Netty 4.0.44.Final. Resolved the issue by excluding the Netty dependencies and added Netty 4.0.44.Final as the required dependency. Which was already reported by some users.
cassandra-1535