As we know, a Hadoop cluster consists of master and slave servers: MasterNodes—to manage the infrastructure, and SlaveNodes—distributed data store and data processing. EdgeNodes are not a part of the Hadoop cluster. This machine is used to interact with the Hadoop cluster. Users are not given any permission to directly log in to any of the MasterNodes and DataNodes, but they can log in to the EdgeNode to run any jobs on the Hadoop cluster. No application data is stored on the EdgeNode. The data is always stored on the DataNodes on the Hadoop cluster. There can be more than one EdgeNode, depending on the number of users running jobs on the Hadoop cluster. If enough hardware is available, it's always better to host each master and DataNode on a separate machine. But, in a typical Hadoop cluster, there are three MasterNodes.
Please note...