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Unable to format NameNode - PseudoNode cluster

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Expert Contributor

Hi,

I have just built a Pseudo Node cluster following below article:

 

http://www.cloudera.com/content/www/en-us/documentation/enterprise/latest/topics/cdh_qs_yarn_pseudo....

 

Initally I had missed to install Java however, after getting below error while formatting NameNode I installed Java 1.6:

JAVA_HOME is not set and could not be found.

Even after installing it (jdk-6u31-linux-amd64.rpm), I am still getting below error (a bit different but I guess related to Java). I feel I need to explicitly set the paths in .bashrc, hadoo-env.sh and /etc/profile files (not sure though). I am unsure how do I do it for the same (as I am pretty new to Linux and Hadoop).

 

[node1@primary ~]$ sudo -u hdfs hdfs namenode -format
[sudo] password for node1: 
Exception in thread "main" java.lang.UnsupportedClassVersionError: org/apache/hadoop/hdfs/server/namenode/NameNode : Unsupported major.minor version 51.0
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
	at java.net.URLClassLoader.access$000(URLClassLoader.java:58)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
Could not find the main class: org.apache.hadoop.hdfs.server.namenode.NameNode.  Program will exit.
[node1@primary ~]$ java -version
java version "1.6.0_31"
Java(TM) SE Runtime Environment (build 1.6.0_31-b04)
Java HotSpot(TM) 64-Bit Server VM (build 20.6-b01, mixed mode)
[node1@primary ~]$ 


Would be great if someone could help.

 

Thanks

snm1523

1 ACCEPTED SOLUTION

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Mentor
CDH5 is compiled with JDK7, and will not run with a lesser JDK version (such as 6, which is no longer supported). Please install JDK7 from http://archive.cloudera.com/cm5/redhat/6/x86_64/cm/5/RPMS/x86_64/oracle-j2sdk1.7-1.7.0+update67-1.x8... or use JDK8 from http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

Please also remove JDK6 to avoid confusion in selection of the right JVM to run with.

View solution in original post

2 REPLIES 2

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Mentor
CDH5 is compiled with JDK7, and will not run with a lesser JDK version (such as 6, which is no longer supported). Please install JDK7 from http://archive.cloudera.com/cm5/redhat/6/x86_64/cm/5/RPMS/x86_64/oracle-j2sdk1.7-1.7.0+update67-1.x8... or use JDK8 from http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

Please also remove JDK6 to avoid confusion in selection of the right JVM to run with.

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Expert Contributor

Thank you for the help, Harsh.

 

Have updated to version 1.8.0_65 which worked.

 

Thanks

Snm1523