The assigned MapReduce tutorial on YDN provided a detailed lesson on MapReduce execution and the basics of coding the MapClass and Reduce classes. I thought it was clearly presented and the checkpoint assignment was effective, if not too challenging. As another blogger noted, it may be necessary to reload the tutorial several times to get it to load successfully. But the persistence was worth it.

The article linked below includes a MapReduce example but is more focused on the cluster components and how the Hadoop architecture operates both to provide the HDFS and to execute MapReduce jobs. I found it helpful to understand a bit more of the bigger Hadoop picture in the context of a MapReduce job execution.

http://bradhedlund.com/2011/09/10/understanding-hadoop-clusters-and-the-network/

From the blog kevpfowler » wsu-cs by kevpfowler and used with permission of the author. All other rights reserved by the author.