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Intelligent Agent Overview

This chapter provides a brief overview of the Intelligent Agent. The following topics are covered:

Oracle Intelligent Agent: An Overview

The Oracle Intelligent Agent is an autonomous process running on a remote node in the network. The Agent resides on the same node as the service it supports. However, the Agent can support more than one service on a particular node. For example, if two databases are installed on one machine, a single Agent can support both databases. The Agent is responsible for:

Providing local services or calling operating system dependent services to interact locally with the managed targets.
Accepting jobs or events from the Oracle Management Server or other third-party applications.
Running Oracle Enterprise Manager jobs, collecting their results and output, and/or queuing the results as required.
Checking for events, and queueing the resulting event reports for Oracle Enterprise Manager.
Canceling jobs or events as directed by the Console or other applications.
Handling Simple Network Management Protocol (SNMP) requests, if SNMP is supported on the Agent's platform.

For information on configuring the Agent, see the Oracle server platform-specific installation documentation for your system.

Note:
Enterprise Manager version 1 does not use version 2's middle-tier Management Server. Because this manual is geared towards users of both version 1 and version 2, users of Enterprise Manager version 1 should ignore references to the Management Server.

Characteristics

Intelligent Agents are autonomous because they function without requiring that the Console or Management Server be running. An Agent that services a database can run when the database is down, allowing the Agent to start up or shut down the database. The Intelligent Agents can independently perform administrative job tasks at any time, without active participation by the administrator. Similarly, the Agents can autonomously detect and react to events, allowing them to monitor the system and execute a fixit job to correct problems without the intervention of the administrator.

The Agents operate independently of the Console and Management Server and are able to execute jobs and monitor events when the administrator has logged out of the Console. The Agents queue any job or event messages destined for that administrator, and deliver them to the Management Server. When the administrator logs in to a Console again, the Management Server delivers pending messages to the administrator who is currently logged in. Information about the state of jobs and events are stored in files on the Agent's node. These files have a ".q" extension and are stored in the $ORACLE_HOME/network/agent directory.

Job and Event Support

Jobs and events are implemented as Tcl scripts. When the Agent executes a job or tests for an event, it runs the appropriate Tcl script.

When the Management Server sends a message to an Agent on behalf of an administrator logged into the Console, it also sends the information about the administrator's language and character set environment. The Agent uses the NLS environment information when it performs database administration tasks on behalf of the administrator. This allows administrators to manage databases in their native languages. For example, an administrator in France can administer a database in Germany and receive messages in French.

Simple Network Management Protocol Support

The Agent supports Simple Network Management Protocol (SNMP), allowing third-party systems management frameworks to use SNMP to receive SNMP traps directly from the Agent. The Agent provides access to Oracle's database Management Information Base (MIB) variables. You can submit jobs or events that access Oracle MIB variables even when the database resides on a platform that does not support SNMP. For more information on SNMP, see the Oracle SNMP Support Reference Guide.

Description of the Data Gathering Service

The data gathering service (also known as Oracle Data Gatherer) is used to collect performance data.

The Oracle Data Gatherer is responsible for handling requests from client applications (for example, Oracle Capacity Planner and Oracle Performance Manager) that want to collect data. For each client application, you specify the performance data to collect (for example, file I/O or CPU usage data) and the time interval between data samples. The Oracle Data Gatherer then collects the requested data for the client at the specified interval.

How the Data Gathering Service is Installed

The Oracle Data Gatherer is part of the Oracle Intelligent Agent, and it is automatically installed when the Agent is installed on a managed host. Therefore, in the following sections, any reference to the Oracle Data Gatherer being installed on a host means that the Oracle Data Gatherer service was installed on the host when the Agent was installed on the host.

Understanding Where to Configure the Oracle Data Gatherer to Collect Database and Operating System Data

The Oracle Data Gatherer collects performance data for:

databases
operating systems
other supported sources

In general, the Oracle Data Gatherer should be configured on the host where the target (database or host) to be monitored is physically located. In other words, if you want the Oracle Data Gatherer to collect database data from the MEDICAL database on host BENEFITS, then the Oracle Data Gatherer should be installed and configured on host BENEFITS. Similarly, if you want the Oracle Data Gatherer to collect operating system data on host EMPLOYEES, then the Oracle Data Gatherer should be installed and configured on host EMPLOYEES.

In some cases, however, it may not be possible to install and configure the Oracle Data Gatherer on a particular host. The Oracle Data Gatherer can be installed on a host only when both the following requirements are met:

The host operating system must support the installation and configuration of the Oracle Data Gatherer.
An Oracle Home for Oracle 8.0.4 or later must exist on the host. Note that the host does not have to have an Oracle 8.0.4 or later database, just an Oracle Home directory for Oracle 8.0.4 or later.

If a host does not meet these requirements, the Oracle Data Gatherer cannot be installed on the host, which means that the Oracle Data Gatherer will not be able to collect operating system statistics from the host. However, you can collect database data from a host on which the Oracle Data Gatherer cannot be installed and configured.

Running the Oracle Data Gatherer on an Intermediate Host

To collect database data from a host on which the Oracle Data Gatherer cannot be installed and configured, install and configure the Oracle Data Gatherer on a different host that meets both of the requirements. You can then use the Oracle Data Gatherer on this host to collect database data remotely on hosts that do not have the Oracle Data Gatherer installed. This is called using an intermediate host Oracle Data Gatherer.

For example, suppose you want to collect database data for the CONSULTANTS database on host EMPLOYEES, but the Oracle Data Gatherer cannot be installed and configured on host EMPLOYEES. If the Oracle Data Gatherer is installed and configured on host BENEFITS, you can use the Oracle Data Gatherer on BENEFITS as an intermediate host Oracle Data Gatherer. The Oracle Data Gatherer on BENEFITS is able to collect database statistics from the CONSULTANTS database on host EMPLOYEES.

You might also want to use an intermediate host Oracle Data Gatherer if an additional process footprint/overhead cannot be tolerated on the host where you want to collect database data. Of course, in this situation the collection activity will still take place against the database. This minimal collection activity overhead will be present regardless of the host where the Oracle Data Gatherer is located.

1 Intelligent Agent Overview