Druid haddop issue

2018-02-12T08:07:16,620 INFO [task-runner-0-priority-0] org.apache.hadoop.mapreduce.Job - Task Id : attempt_1518156998077_0251_r_000021_2, Status : FAILED

Error: org.apache.hadoop.mapreduce.task.reduce.Shuffle$ShuffleError: error in shuffle in fetcher#1

at org.apache.hadoop.mapreduce.task.reduce.Shuffle.run(Shuffle.java:134)

at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:376)

at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)

at java.security.AccessController.doPrivileged(Native Method)

at javax.security.auth.Subject.doAs(Subject.java:422)

at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1709)

at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)

Caused by: java.io.IOException: Exceeded MAX_FAILED_UNIQUE_FETCHES; bailing-out.

at org.apache.hadoop.mapreduce.task.reduce.ShuffleSchedulerImpl.checkReducerHealth(ShuffleSchedulerImpl.java:366)

at org.apache.hadoop.mapreduce.task.reduce.ShuffleSchedulerImpl.copyFailed(ShuffleSchedulerImpl.java:288)

at org.apache.hadoop.mapreduce.task.reduce.Fetcher.openShuffleUrl(Fetcher.java:282)

at org.apache.hadoop.mapreduce.task.reduce.Fetcher.copyFromHost(Fetcher.java:323)

at org.apache.hadoop.mapreduce.task.reduce.Fetcher.run(Fetcher.java:193)

I have attached the log file.

Can anybody help me out in this ? I can ping from master to all slaves noedes.

index_hadoop_device_cap_2018-02-12T08:03:36.501Z.log (354 KB)

You can ping, but can you also connect over tcp using all the ports that Hadoop needs? Sometimes ping works but tcp connecting does not.