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The following page has been changed by CosminLehene:
http://wiki.apache.org/hadoop/NameNodeFailover

The comment on the change is:
Question/idea regarding the name node failover

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  In order to provide redundancy for data protection in case of namenode 
failure the best way is to store the namenode metadata on a different machine.  
Hadoop has an option to have multiple namenode directories and the recommended 
option is to have one of the namenode directories on an NFS share.  However you 
have to make sure the NFS locking will not cause problems and it is NOT 
recommended to change this on a live system because it can corrupt namenode 
data.  Another option is to simply copy namenode metadata to another machine.
  --Ankur Sethi
  
+ '''Question'''
+ 
+ Why not keep the fsimage and editlog in the DFS (somehow that they could be 
located by data nodes without the name node)?
+ Then when then name node fails, by an election mechanism, a data node becomes 
the new name node. 
+ --Cosmin Lehene
+  
+ 

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