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Backup NameNode metadata in HA configuration

+6 votes
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We are using following version of Hadoop software: 2.0.0-cdh4.1.1. HDFS HA configuration is applied.

I would like to ask if there are any difference or possible side effects of backing up namenode data directory.

It is ok to just copy NN data directory from active NN to another host, what about standby NN? Or it may NN metadate can be in inconsistent state? Is there any advantages of using "hdfs dfsadmin -fetch " command?

posted Jan 31, 2014 by Dewang Chaudhary

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