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Failed Map Attempt task executing on same host


Failed Map Attempt task executing on same host

New Contributor

Hi Everyone, 


1) One of the map attempt task of very critical MR job (which runs every day)  got failed four times -- out of 4 times first attempt got failed  on one host( after 2hours 4 min.  but 2nd , 3rd and 4th attempt  were  failed on the same host( . The execution time gap among of these 3 attempts like 3 sec. having some build issues so 2nd time got failed but ideally 3rd  attempt should be triggered in a different host rather than on same host.


Logs (2nd attempt)

WARN [main] org.apache.hadoop.mapred.YarnChild: Exception running child : java.lang.RuntimeException: WritableName can't load class:

Caused by: WritableName can't load class: at at$Reader.getValueClass(


Please share your  suggestions to fix this issue as this is very critical job. 


2 ) Is there any way set the Map reducer configuration  properties from CMD level rather than config files in  Cloudera  or code level or while submitting job  .If so what is the command to set . Kindly share those details


Re: Failed Map Attempt task executing on same host

New Contributor
  1. Hi. Can show me your code what are you trying to do so that I can try to help you out
  2. Yes, you can change YARN configuration from Cloudera,
    1. Follow this path: YARN -> CONFIGURATION -> search any property you want to change and make change


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