I woke up to an alert from our Cloudera Manager managed Hadoop cluster: Error: Aug 15, 2:46:01.285 PM WARN org.apache.hadoop.security.UserGroupInformation PriviledgedActionException as:hdfs (auth:SIMPLE) cause:org.apache.hadoop.hdfs.qjournal.protocol.JournalNotFormattedException: Journal […]
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HDFS Under Replicated Blocks
This is an HDFS service-level health check that checks that the number of under-replicated blocks does not rise above some percentage of the cluster’s total […]
Continue readingCopy data from one Hadoop cluster to another Hadoop cluster (running different versions of Hadoop)
I had to copy data from one Hadoop cluster to another recently. However, the two clusters ran different versions of Hadoop, which made using distcp […]
Continue readingUsing Cloudera Manager I found it very easy to configure single-node Hadoop development nodes that can be used by our developers to test their Pig […]
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