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Kafka >> mail # user >> Getting LeaderNotAvailableException in console producer after increasing partitions from 4 to 16.


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Re: Getting LeaderNotAvailableException in console producer after increasing partitions from 4 to 16.
Thanks Neha & Guozhang,

When I ran StateChangeLogMerger, I am seeing this message repeated 16 times
for each partition:

[2013-08-27 12:30:02,535] INFO [ReplicaFetcherManager on broker 1] Removing
fetcher for partition [test-60,13] (kafka.server.ReplicaFetcherManager)
[2013-08-27 12:30:02,536] INFO [Log Manager on Broker 1] Created log for
partition [test-60,13] in
/home/relango/dev/mandm/kafka/main/target/dist/mandm-kafka/kafka-data.
(kafka.log.LogManager)

I am also seeing .log and .index files created for this topic in data dir.
Also list topic command shows leaders, replicas and isrs for all
partitions. Do you still think increasing num of retries would help or is
it some other issue..? Also console Producer doesn't seem to  have option
to set num of retries. Is there a way to configure num of retries for
console producer ?

Thanks,
Raja.
On Tue, Aug 27, 2013 at 12:52 PM, Neha Narkhede <[EMAIL PROTECTED]>wrote:

> As Guozhang said, your producer might give up sooner than the leader
> election completes for the new topic. To confirm if your producer gave up
> too soon, you can run the state change log merge tool for this topic and
> see when the leader election finished for all partitions
>
> ./bin/kafka-run-class.sh kafka.tools.StateChangeLogMerger --logs <location
> to all state change logs> --topic <topic>
>
> Note that this tool requires you to give the state change logs for all
> brokers in the cluster.
>
>
> Thanks,
> Neha
>
>
> On Tue, Aug 27, 2013 at 9:45 AM, Guozhang Wang <[EMAIL PROTECTED]> wrote:
>
> > Hello Rajasekar,
> >
> > In 0.8 producers keep a cache of the partition -> leader_broker_id map
> > which is used to determine to which brokers should the messages be sent.
> > After new partitions are added, the cache on the producer has not
> populated
> > yet hence it will throw this exception. The producer will then try to
> > refresh its cache by asking the brokers "who are the leaders of these new
> > partitions that I do not know of before". The brokers at the beginning
> also
> > do not know this information, and will only get this information from
> > controller which will only propagation the leader information after the
> > leader elections have all been finished.
> >
> > If you set num.retries to 3 then it is possible that producer gives up
> too
> > soon before the leader info ever propagated to producers, hence to
> > producers also. Could you try to increase producer.num.retries and see if
> > the producer can eventually succeed in re-trying?
> >
> > Guozhang
> >
> >
> > On Tue, Aug 27, 2013 at 8:53 AM, Rajasekar Elango <
> [EMAIL PROTECTED]
> > >wrote:
> >
> > > Hello everyone,
> > >
> > > We recently increased number of partitions from 4 to 16 and after that
> > > console producer mostly fails with LeaderNotAvailableException and
> exits
> > > after 3 tries:
> > >
> > > Here is last few lines of console producer log:
> > >
> > > No partition metadata for topic test-41 due to
> > > kafka.common.LeaderNotAvailableException}] for topic [test-41]: class
> > > kafka.common.LeaderNotAvailableException
> > >  (kafka.producer.BrokerPartitionInfo)
> > > [2013-08-27 08:29:30,271] ERROR Failed to collate messages by topic,
> > > partition due to: Failed to fetch topic metadata for topic: test-41
> > > (kafka.producer.async.DefaultEventHandler)
> > > [2013-08-27 08:29:30,271] INFO Back off for 100 ms before retrying
> send.
> > > Remaining retries = 0 (kafka.producer.async.DefaultEventHandler)
> > > [2013-08-27 08:29:30,372] INFO Secure sockets for data transfer is
> > enabled
> > > (kafka.producer.SyncProducerConfig)
> > > [2013-08-27 08:29:30,372] INFO Fetching metadata from broker
> > > id:0,host:localhost,port:6667,secure:true with correlation id 8 for 1
> > > topic(s) Set(test-41) (kafka.client.ClientUtils$)
> > > [2013-08-27 08:29:30,373] INFO begin ssl handshake for localhost/
> > > 127.0.0.1:6667//127.0.0.1:36640 (kafka.security.SSLSocketChannel)
> > > [2013-08-27 08:29:30,375] INFO finished ssl handshake for localhost/

Thanks,
Raja.