This section introduces some fundamental terminology and explains in more detail the RGM and its associated interfaces.
The RGM handles three major kinds of interrelated objects: resource types, resources, and resource groups. One way to introduce these objects is by means of an example, as follows.
You implement a resource type, ha-oracle, that makes an existing Oracle DBMS application highly available. An end user defines separate databases for marketing, engineering, and finance, each of which is a resource of type ha-oracle. The cluster administrator places these resources in separate resource groups so that they can run on different nodes and fail over independently. You create a second resource type, ha-calendar, to implement a highly available calendar server that requires an Oracle database. The cluster administrator places the resource for the finance calendar into the same resource group as the finance database resource. The cluster administrator does so to ensure that both resources run on the same node and fail over together.