Problems exception faced in hadoop set up





1.  Data node in not starting namespace ID mismatch. 
Reason:  
Every time the NameNode reformats it generats a new namespace ID, and some of your machines didn't get the memo. 

Sloution: 
The easiest way to fix this problem is by reformatting the distributed filesystem. Delete hadoop temp folder (/usr/local/hadoop/hadoop-tmp)on each server (the directory path may be different depending on your configuration). Then run hadoop namenode -formatfrom your master server. After that,start-all.sh should do the trick.


2. Hadoop master and Slave version must be same 

Comments

  1. UnknownJuly 8, 2016 at 6:21 AM

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