Hadoop Warning Unable to load Native-Hadoop Library for your platform

Question

I am using the CentOS and trying to run my Hadoop Cluster on the CentOS Server. I have tried to start all environment variables in .sh file using the following command

#start-dfs.sh

and tried to stop it using the following command

#stop-dfs.sh

None of both work and above that am receiving an error saying.

#WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable

My current version of Hadoop is 2.2.0 and I have tried to google the error which popped this link up

Strange thing is that the contents of /native/ directory on hadoop 2.x appear to be different so I am not sure what to do.

I've also added these two environment variables in Hadoop-env.sh file

#export HADOOP_OPTS="$HADOOP_OPTS -Djava.library.path=/usr/local/hadoop/lib/"
#export HADOOP_COMMON_LIB_NATIVE_DIR="/usr/local/hadoop/lib/native/"

Someone, please help me out on this one.

Answer 1

Are you sure you're running Hadoop on 32bit CentOS? 

I think the reason you saw that warning is the native Hadoop library $HADOOP_HOME/lib/native/libhadoop.so.1.0.0 is that it is actually expected to be compiled on a 32 bit CentOS.

It's just a warning, and won't impact Hadoop's functionalities.

If you are running CentOS 64 bit then I would suggest you to download the source code of Hadoop and recompile libhadoop.so.1.0.0 on a 64bit system, then replace the 32bit one.

Even then if the Warning is existing, then you can follow the following solution.

Steps on how to recompile source code are included here for Ubuntu:

solve this issue by ingesting these lines into my .bashrc file.

#export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_HOME/lib/native
#export HADOOP_OPTS="-Djava.library.path=$HADOOP_HOME/lib"

This must resolve your issue.