Hello world in zeppelin failed

Question

I just installed apache zeppelin (built from latest source from git repo) and successfully saw it is up and running in the port 10008. I created a new note book with a single line of code

val a = "Hello World!"

And run this paragraph and saw the below error

java.net.ConnectException: Connection refused at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) at java.net.Socket.connect(Socket.java:589) at org.apache.thrift.transport.TSocket.open(TSocket.java:182) at org.apache.zeppelin.interpreter.remote.ClientFactory.create(ClientFactory.java:51) at org.apache.zeppelin.interpreter.remote.ClientFactory.create(ClientFactory.java:37) at org.apache.commons.pool2.BasePooledObjectFactory.makeObject(BasePooledObjectFactory.java:60) at org.apache.commons.pool2.impl.GenericObjectPool.create(GenericObjectPool.java:861) at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:435) at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:363) at org.apache.zeppelin.interpreter.remote.RemoteInterpreterProcess.getClient(RemoteInterpreterProcess.java:139) at org.apache.zeppelin.interpreter.remote.RemoteInterpreter.init(RemoteInterpreter.java:137) at org.apache.zeppelin.interpreter.remote.RemoteInterpreter.getFormType(RemoteInterpreter.java:257) at org.apache.zeppelin.interpreter.LazyOpenInterpreter.getFormType(LazyOpenInterpreter.java:104) at org.apache.zeppelin.notebook.Paragraph.jobRun(Paragraph.java:197) at org.apache.zeppelin.scheduler.Job.run(Job.java:170) at org.apache.zeppelin.scheduler.RemoteScheduler$JobRunner.run(RemoteScheduler.java:304) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) 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

Any clue?

My backend is spark 1.5 and I verified by web interface of interpreter that zeppelin points to right version of spark and approproate spark.home.

Answer 1

The error may be casued also du to an error occurred while Zeppelin trying to create the interpreter.

Zeppelin starts the interpretter in a different process and tries to connect to using Thrift Protocol

In my case I ve this error when trying to assign 5GB for spark driver in spark-defaults.conf It is resolved when commenting this line (or assign 4g or less)

#spark.driver.memory              5g

You could have a look at this JIRA ZEPPELIN-305

EDIT:

This error could be caused by any reason that prevents the Spark interpreter process from starting. Recently, I ve got it when trying to add the JMX options to ZEPPELIN_JAVA_OPTS, that cause the interpreter process to use the same JMX port as the Zeppelin process. Giving the "Port Already in Use" error

Please check the Zeppelin logs (by default they are in ZEPPELIN_DIR/logs/ to see what is happening when Zeppelin trying to start Spark Interpreter