Architecture   and   Configuration     




Component Diagram


OBIEE has a very complex architecture with many components.  We’ll start this set of articles with a simplified diagram that shows the main components of OBIEE and how they are interconnected.  Then, in subsequent articles, we’ll examine each component in more detail.

OBIEE Basic Components



Basic Functionality


Let’s start at the bottom of the diagram and work upwards.  Access to various heterogeneous data sources is by means of the BI Server instances.


The BI Presentation Services instances and other BI Server clients access the BI Server instances via an ODBC Data Source.


The BI Cluster Controller instances monitor the “health” of the BI Server instances and the BI Scheduler instances.  They also act as an “introduction agency” for the BI Presentation Services instances and other BI Server clients, passing back to an enquiring client the address of a “suitable” BI Server instance or BI Scheduler instance, with which the client will subsequently engage in direct conversation, in the case of the BI Scheduler instances, or via the ODBC data source, in the case of the BI Server instances.


Whereas the BI Server instances return query results to their clients, the BI Presentation Services instances return formatted query results to theirs, in the form of reports and charts (the BI JavaHost instances provide support services to both the Presentation Service instances and the Scheduler instances).  The most immediate of the BI Presentation Services clients are the BI Scheduler instances – internal clients – that send queries and receive query results according to a predefined timetable.  Other BI Presentation Services clients, such as web browsers and web services, access the BI Presentation Services instances via the HTTP Servers and the J2EE Servers.


At the beginning of a client session a particular BI Server instance, and in the case of a BI Presentation Services client a BI Presentation Services instance, are allocated to the client for the duration of the session.


Most components of OBIEE can be clustered in a “many-to-many” architecture.  In the diagram, all the internal components, apart from the Load Balancer, occur in multiples to facilitate failover and to ensure adequate performance.