Oracle Grid Control 11g Release 1 comprises three components: the Oracle Management Service (OMS), the Oracle Management Repository, and the Oracle Management Agent. We will briefly explain the purpose of each of these components to provide insight into how they function as a single unit known as Grid Control.
- Oracle Management Agent The Management Agent software is deployed to each monitored host. This agent collects data about the configured targets (such as the database, ASM, and so on) on that host and uploads that data via HTTP or HTTPS to the OMS for processing. The Management Agent is also responsible for executing host- or target-level tasks as instructed by the OMS.
- Oracle Management Service You’re probably thinking that this is the component that generates the web interface for Grid Control. Although you are entirely correct, the OMS is a Java 2 Platform, Enterprise Edition (J2EE) application that does much more than that. It is the brain behind Grid Control. It instructs the Management Agents on what aspects of a given target to monitor, at what interval to monitor the targets, what credentials are to be used for monitoring, and so on. In addition to sending directives to the Management Agents, it is also in charge of storing data uploaded from Management Agents for storage in the Management Repository (later to be used for historical trending, reporting, and so on), rendering of charts/graphs from this data, and sending of user notifications via e-mail. All communication between the OMS and agents is via HTTP or HTTPS.
- Oracle Management Repository This component is a schema comprising various tables, views, packages, procedures, and jobs within an Oracle database. The Management Repository processes and stores the information received by Oracle Management Server. All target configuration information and collected data from the Management Agents is stored within this Management Repository, allowing for multiple Oracle Management Servers to access the same information simultaneously.
With Oracle Grid Control’s centralized management of the grid, you will depend on it for monitoring and administration. For this reason, Grid Control is easily configurable in a MAA implementation involving an Oracle RAC/Oracle Data Guard Management Repository and multiple Oracle Management Servers accessed centrally using a load balancer. Although this type of implementation is well beyond the scope of this chapter, it is definitely a topic for consideration as your dependency on Oracle Grid Control grows.