Introduction
Ambari supports the concept of Stacks and associated Services. Using Stack definition, Ambari has a consistent and defined interface to install, manage and monitor a set of Services and provides extensibility model for new Stacks + Services to be introduced.
Terminology
Stack = defines a set of Services and where to obtain the software packages for those Services. A Stack can have one or more version, and each version can be active/inactive. For example, Stack = "HDP-1.3.3".
Service = defines the Components (MASTER, SLAVE, CLIENT) that make up the Service. For example, Service = "HDFS"
Components = defines and adhere to a certain defined lifecycle (start, stop, install, etc). For example, Service = "HDFS" has Components = "NameNode (MASTER)", "Secondary NameNode (MASTER)", "DataNode (SLAVE)" and "HDFS Client (CLIENT)"
In Practice
In Ambari 1.4.x or earlier, refer to Overview (Ambari 1.4.x or earlier) for more information
In Ambari 1.5.0 or later, refer to Overview (Ambari 1.5.0 or later) for more information