TechTests TechTests articles. en-US ?2011 TechTests. All Rights Reserved. Hardware configuration for a poc/test hadoop cluster ? Daemons Before going deeper into hardware configuration, let's first see what different daemons are there in hadoop.? NameNode SecondaryNameNode JobTracker DataNode TaskTracker In a small cluster, NN, SNN and JT are on same machine. DN and TT are always on same. Mon, 29 Apr 2013 00:00:00 GMT Enum in Java ? For those of us who were coding extensive development in Java even before Java 1.5 know the pain faced before enum was introduced. The solution used to be Type-safe Enums which was a design pattern to simulate enum functionality as closely as possible.? Introduction of enums changed. Thu, 11 Apr 2013 00:00:00 GMT Creating a Simple SOAP Web Service using Maven in 5 Steps SOAP SOAP stands for simple object access protocol. In this SOAP Service we'll have 4 classes ? ? ? ? ? ? ? ? pom.xml pom.xml for this project is barebones as java 6 onwards provide native. Wed, 27 Mar 2013 00:00:00 GMT Who is this SecondaryNameNode anyway SecondaryNameNode is one of the most confusing things in Hadoop.? There are not many books in Hadoop and I happened to be reading one and I quit reading the book the moment I saw this sentence. "The NameNode is a single point of failure, and on failure it will stop all the operations of the. Mon, 11 Feb 2013 00:00:00 GMT