Hadoop is a distributed framework with two important components: HDFS and MapReduce. Hadoop has two main versions: Hadoop 1.0 and Hadoop 2.0. The original Hadoop 1.0 has NameNode, DataNode, JobTracker, and TaskTracker. In Hadoop 2.0, a new YARN framework has come into picture, which replaces JobTracker and TaskTracker with ResourceManager and NodeManager respectively. HDFS is the File System or the storage layer, and MapReduce is the programming model.
Each layer has a master and a slave to handle the communication and coordination between them. In order to set up monitoring, it is important to take into account the services and ports used by each node.
NameNode is the master node that takes care of the HDFS File System. There are many important things to take care in NameNode in terms of services and ports. The following table lists parameters which need to be monitored:
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Parameter |
Description |
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This is the parameter in |