Re: [storm-user] spouts and bolts not emitting data in the STORM UI

[Nathan Marz]

Please provide:

1. Storm version

2. Is there anything unusual in the worker logs?

3. A reproducible test case

On Wed, Nov 7, 2012 at 3:41 AM, CR_Stormuser <chitra.r...@fluturasolutions.com> wrote:

Hi 

 

I've a storm topology which works perfect locally. 

When I try to submit it to cluster consisting of 2 supervisors and 1 nimbus, The maven compile and packaging builds are successful and The topology gets submitted to cluster, but in the storm UI, even though the topology is ACTIVE, the spout nor the bolts seem to be emitting data

This the only modification I've made to the topology for to make it run in a cluster.

if(args!=null && args.length > 0) {
           conf.setNumWorkers(3);
           
           StormSubmitter.submitTopology(args[0], conf, builder.createTopology());
       } else {
       
           LocalCluster cluster = new LocalCluster();
           cluster.submitTopology("test", conf, builder.createTopology());
           Utils.sleep(800);
           cluster.killTopology("test");
           cluster.shutdown();    
       }

 Regards

--
Twitter: @nathanmarz
http://nathanmarz.com

[CR_Stormuser]

Hi Nathan

1.My storm version in 0.8.0

2.I'll attach the supervisor, nimbus and ui logs.

 I'd successfully ran exclamation topology in cluster by the name test-topology, but after that i tried to submit a new topology test2.That's when i encountered the problem in the STORM UI where I couldn't see the spout n bolts emit data.

I tried killing topologies and starting daemons again.With no positive result.

After a few tries I am not even able to view the storm ui. My nimbus, supervisor and ui daemons seem to be crashing as soon as i launch them.

Please help. Can't figure out what went wrong suddenly 

Thanks

[CR_Stormuser]

Hi

The maven compile and package build works fine with build successful when I commented the settings in my storm.yaml. But on submitting  the storm jar the Storm ui shows the topology ACTIVE, but there are'nt any spout or bolts emitting data and the SPOUT is seen to give this

 SPOUT ERROR:

java.lang.NullPointerException at storm.starter.spout.DBSampleSpout.nextTuple(DBSampleSpout.java:104) at backtype.storm.daemon.executor$fn__3968$fn__4009$fn__4010.invoke(executor.clj:433) at backty

I'll attach a screen shot of the ui:

The error points to this line of my spout code:

prepstmt = con.prepareStatement(stmt);

Please help !

Regards

On Thursday, November 8, 2012 12:43:00 AM UTC+5:30, nathanmarz wrote:

[Nathan Marz]

It's a problem with your code. Looks like "con" is null. You probably need to create "con" in the prepare method of the bolt. Read http://nathanmarz.github.com/storm/doc/backtype/storm/task/IBolt.html to see the lifecycle of a component.

[CR_Stormuser]

Thanks Nathan

My con was null, i created con in the prepare method like u said and its up and running now. Problem solved .!!!

But I've noticed a new problem, I'm reading an mysql table ( 1272 rows  ) and processing it. At the end of the pipeline, the output table gets written row by row, so finally it should have 1272 rows. But I have noticed that, the output table starts getting written from beginning, once 1272 rows are reached. 

After 1272 rows, it truncates output table and whole process keeps repeating in a cyclic fashion. Why is this so ?

Thanks