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Exceeded MAX_FAILED_UNIQUE_FETCHES; bailing-out

Exceeded MAX_FAILED_UNIQUE_FETCHES; bailing-out

New Contributor

Hi, Team


I have a problem when querying select count(*) from table atau select distinct field from table atau select * from table order by field.


when checked through yarn, then application details.

error appears :


2017-10-03 16:22:54,826 INFO [IPC Server handler 12 on 35262] org.apache.hadoop.mapred.TaskAttemptListenerImpl: Progress of TaskAttempt attempt_1506588001647_0368_r_000000_0 is : 0.21282798
2017-10-03 16:22:54,827 FATAL [IPC Server handler 10 on 35262] org.apache.hadoop.mapred.TaskAttemptListenerImpl: Task: attempt_1506588001647_0368_r_000000_0 - exited : org.apache.hadoop.mapreduce.task.reduce.Shuffle$ShuffleError: error in shuffle in fetcher#3
at org.apache.hadoop.mapred.YarnChild$
at Method)
at org.apache.hadoop.mapred.YarnChild.main(
Caused by: Exceeded MAX_FAILED_UNIQUE_FETCHES; bailing-out.
at org.apache.hadoop.mapreduce.task.reduce.ShuffleSchedulerImpl.checkReducerHealth(
at org.apache.hadoop.mapreduce.task.reduce.ShuffleSchedulerImpl.copyFailed(
at org.apache.hadoop.mapreduce.task.reduce.Fetcher.openShuffleUrl(
at org.apache.hadoop.mapreduce.task.reduce.Fetcher.copyFromHost(


can be helped on this 


Many Thanks


Re: Exceeded MAX_FAILED_UNIQUE_FETCHES; bailing-out


could you fire the below commands in master and slave 

netstat -anp | grep 50060

also see if you can ping your slave from master and vice versa 

looks like issue between them 

Re: Exceeded MAX_FAILED_UNIQUE_FETCHES; bailing-out

New Contributor
Hi csguna
Thanks For Support, can be explained, just host Task Tracker or include the master host, because if not the host task tracker status closed ?

what about the host job tracker, where the port is 50030, if the check must be closed port ?