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https://issues.apache.org/jira/browse/MAPREDUCE-7152?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17903041#comment-17903041
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wuchang commented on MAPREDUCE-7152:
------------------------------------

[~pbacsko] May I know more details for this? I exactly meet the same issue on 
my Hadoop Yarn cluster in which different NodeManagers have different running 
location.  I configure my mapred-site.xml as below:
{code:java}
<property>
<name>mapreduce.reduce.env</name>
<value>LD_LIBRARY_PATH=$HADOOP_COMMON_HOME/lib/native:$JAVA_LIBRARY_PATH:/usr/lib/x86_64-linux-gnu</value>
</property>
<property>
<name>mapreduce.map.env</name>
<value>LD_LIBRARY_PATH=$HADOOP_COMMON_HOME/lib/native:$JAVA_LIBRARY_PATH:/usr/lib/x86_64-linux-gnu</value>
</property>{code}
And all the mappers which run on the same host with ApplicationMaster 
succeeded, all the mappers which run on the different hosts with 
ApplicationMaster failed for Snappy not found issue.

I find that seems that all mappers's LD_LIBRARY_PATH is using the expanded 
value of $HADOOP_COMMON_HOME on ApplicationMaster,  then mappers running on 
different hosts with ApplicationMaster will always fail.

> LD_LIBRARY_PATH is always passed from MR AM to tasks
> ----------------------------------------------------
>
>                 Key: MAPREDUCE-7152
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-7152
>             Project: Hadoop Map/Reduce
>          Issue Type: Improvement
>            Reporter: Peter Bacsko
>            Assignee: Peter Bacsko
>            Priority: Major
>         Attachments: MAPREDUCE-7152-NMAdminEnvPOC_POC01.patch, 
> MAPREDUCE-7152-lazyEval_POC01.patch
>
>
> {{LD_LIBRARY_PATH}} is set to {{$HADOOP_COMMON_HOME/lib/native}} by default 
> in Hadoop (as part of {{mapreduce.admin.user.env}} and 
> {{yarn.app.mapreduce.am.user.env}}), and passed as an environment variable 
> from AM container to task containers in the container launch context.
> In cases where {{HADOOP_COMMON_HOME}} is different in AM node and task node, 
> tasks will fail to load native library. A reliable way to fix this is to add 
> {{LD_LIBRARY_PATH}} in {{yarn.nodemanager.admin-env}} instead.
> Another approach is to perform a lazy evaluation of {{LD_LIBRARY_PATH}} on 
> the NM side.



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