Archivo mensual: octubre 2014

yarn: change configuration and restart node manager on a live cluster


This procedure is to change Yarn configuration on a live cluster, propagate the changes to all the nodes and restart Yarn node manager. Both commands are listing all the nodes on the cluster and then filtering the DNS name to … Seguir leyendo

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Hadoop 1 vs Hadoop 2 – How many slots do I have per node ?


This is a topic that always rise a discussion… In Hadoop 1, the number of tasks launched per node was specified via the settings mapred.map.tasks.maximum and mapred.reduce.tasks.maximum. But this is ignored when set on Hadoop 2. In Hadoop 2 with … Seguir leyendo

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Hadoop useful commands


– Copy fromLocal/ToLocal from/to S3: $ bin/hadoop fs -copyToLocal s3://my-bucket/myfile.rb /home/hadoop/myfile.rb $ bin/hadoop fs -copyFromLocal job5.avro s3://my-bucket/input – Merge all the files from one folder into one single file: $ hadoop jar ~/lib/emr-s3distcp-1.0.jar –src s3://my-bucket/my-folder/ –dest s3://my-bucket/logs/all-the-files-merged.log –groupBy ‘.*(*)’ –outputCodec … Seguir leyendo

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