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HDFS Data Integrity in copyToLocal

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How can I verify the integrity of files copied to local from HDFS? Does HDFS store MD5s of full files anywhere? From what I can find, FileSystem.getFileChecksum() is relevant to replication and not comparison across filesystems.

The Data Integrity section in HDFS Architecture (http://hadoop.apache.org/docs/stable/hadoop-project-dist/hadoop-hdfs/HdfsDesign.html) does not make it clear if, or how, copyToLocal verifies the integrity of the copied file.

posted Dec 18, 2013 by Ahmed Patel

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