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HDFS - Consolidate 2 small volumes into 1 large volume

+2 votes

Is it possible to consolidate two small data volumes (500GB each) into a larger data volume (3TB)?

I'm thinking that as long as the block file names and metadata are unique, then I should be able to shut down the datanode and use something like tar or rsync to copy the contents of each small volume to the large volume.

Will this work?

posted Oct 21, 2014 by anonymous

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1 Answer

+1 vote

Yes, you can.

Stop the cluster, change your hdfs-site.xml on your datanode, (dfs.datanode.dir) to the large volume, copy two small data volumes to the large volumes, which was configured on above, start cluster and you are done.

answer Oct 22, 2014 by Garima Jain
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