Tuesday 4 April 2017



  • A group of inter connected racks is called cluster.
  • A rack can be collection of 30 to 40 nodes.

Types of cluster
  1. Single node cluster or Pseudo-distributed cluster
  2. Multi node cluster or fully distributed cluster
Short definition

  • As the word says,  
    • single node cluster means only one node 
    • multi-node cluster means more than one node

Single Node cluster
  • By default, Hadoop is configured to run on standalone mode, as a single Java process. 
  • All services(daemons) run in a single JVM instance.
Multi-Node cluster
  • All services(daemons) run on different JVM instances on different hosts/machines. 
  • It follows a master-slave architecture.
  • Master - Slave architecture means one machine will act as master node which runs on separate machine and other machines will act as slave node which runs on different machines.
Thanks for your time.