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Oracle Enterprise Manager Concepts Guide
Release 9.0.2

Part Number A95411-01
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Overview of Oracle Enterprise Manager

Oracle Enterprise Manager provides an integrated solution for centrally managing your heterogeneous environment. Combining a graphical console, Oracle Management Servers, Oracle Intelligent Agents, common services, and administrative tools, Oracle Enterprise Manager provides a comprehensive systems management platform for managing Oracle products.

This chapter presents an overview of Oracle Enterprise Manager's benefits, architecture, and major components.

The chapter is divided into the following sections:

Managing Your Entire Oracle Environment

The primary interface to managing your Oracle environment is the Oracle Enterprise Manager Console. The Console is part of the Oracle Enterprise Manager three-tier architecture, which is discussed in more detail later in this chapter.

From the Console, you can perform the following tasks:

Managing Oracle9i Application Server (Oracle9iAS)

For Oracle9iAS Release 2.0, Oracle introduces the Oracle Enterprise Manager Web site, which provides Web-based management tools designed specifically for Oracle9iAS. Using this Web site, you can monitor and configure the components of your Oracle9i Application Server installations. You can deploy applications, manage security, and create and manage Oracle9i Application Server clusters.

Depending on the type of Oracle9iAS installation you support, you can use the Enterprise Manager Web site independently to manage individual Oracle9iAS instances and clusters, or you can use it with the Oracle Enterprise Manager console to manage your entire Oracle environment.

For more information about using the Oracle Enterprise Manager Web site to manage Oracle9iAS, see the Oracle9i Application Server Administrator's Guide. For more information about launching the Oracle Enterprise Manager Web site from the Console, see the Oracle Enterprise Manager Configuration Guide.

Three-Tier Framework

Oracle Enterprise Manager architecture consists of a three-tier framework. Unlike a two-tier client-server structure, where a client tier responsible for the presentation of information accesses data from a server, Oracle Enterprise Manager utilizes a three-tier architecture which includes:

Figure 1-1 Three-Tier Architecture

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With Oracle Enterprise Manager's three-tier framework, data-intensive business logic is moved off the client and is recast as shared services on one or more middle-tier Oracle Management Servers, providing reliability, scalability, and fault tolerance for enterprise environments.

Because not all enterprises need to implement Enterprise Manager as a three tier system, Enterprise Manager is also available in standalone mode, a two-tier framework which connects directly to the databases. The Console launched standalone allows a single person to use one or more applications without requiring an Oracle Management Server or Intelligent Agent.

Use the standalone Console if you want to perform basic administrative tasks that do not require the job, event, or group system.

If you want to use events, jobs, sharing of administrative data, blackouts, groups, enhanced notifications, historical collections, and have the ability to run applications in a web browser, use Enterprise Manager connected to the Management Server. For more information about the standalone Console, see the Oracle Enterprise Manager Configuration Guide.


The first tier of Oracle Enterprise Manager is comprised of clients such as consoles and management applications, which present a graphical user interface to administrators for all management tasks. These client components can be installed locally or brought up with a web browser.

The first-tier clients depend on second-tier Oracle Management Servers for the bulk of their application logic.

Figure 1-2 First Tier

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The Oracle Enterprise Manager Console provides menus, toolbars, and drawers allowing access to Oracle tools.

The Console is partitioned into a two-pane master/detail view of the administrator's global environment. The "master" left pane displays the Navigator tree while the "detail" right pane shows property sheets for objects which are selected within the Navigator. In addition, Events, Jobs, Groups, and Report definitions have been integrated into the Navigator as well.

Figure 1-3 Oracle Enterprise Manager Console

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See Chapter 2, "The Console" for descriptions of the basic components of the Console and how they are organized. For information about the Console menus, see the Oracle Enterprise Manager Administrator's Guide.

Oracle Management Server

The second tier of the Oracle Enterprise Manager framework is comprised of one or more Oracle Management Servers. The Management Server is the core of the Enterprise Manager framework. It provides administrative user accounts, processes management functions such as jobs and events, and manages the flow of information between the Console (first tier) and the nodes with Intelligent Agents (third tier).

Figure 1-4 Management Server

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The Oracle Management Server uses a repository to store all system data, application data, information about the state of managed nodes, and information about any system management packs. A repository is a set of database tables that must be located in a supported Oracle database accessible to the Oracle Management Server.

If necessary, a large enterprise can use more than one Oracle Management Server in the middle tier. When multiple Oracle Management Servers are used, they share and balance the workload, ensuring high performance and scalability.

Figure 1-5 Second Tier

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One of the most important responsibilities of the Oracle Management Server is distributing tasks to the Oracle Intelligent Agents, which run on managed nodes in the third tier. The Intelligent Agents are responsible for the localized execution of tasks and the on-going monitoring of databases and other targets on the managed nodes.

Also, the Administrator can reconnect to a Management Server from within the Console should the Management Server to which the Console was originally connected become unavailable whether due to scheduled maintenance on the node or a power outage in the area where the Management Server resides.

Managed Nodes

The third tier of the Oracle Enterprise Manager framework is comprised of managed nodes which contain databases and other managed targets. Residing on each node is an Oracle Intelligent Agent, which communicates with the Oracle Management Server(s) and performs tasks sent by consoles and client applications.

Figure 1-6 Third Tier

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The Oracle Intelligent Agent monitors databases and other targets in the node for registered events (potential problem occurrences) and scheduled jobs (activities), both sent by the client via the middle-tier Oracle Management Server(s).

Intelligent Agents function independently of the databases and other targets they support, and also function independently of the Console, management applications, and Oracle Management Servers. By running independently of other components, Intelligent Agents can perform such tasks as starting up and shutting down a database and staying operational if another part of the system is down.

In the Intelligent Agent version 9.0.1, the Intelligent Agent process will be automatically restarted in cases where the Intelligent Agent process exits due to an abnormal condition within the environment in which the Intelligent Agent is running.

Intelligent Agents support Simple Network Management Protocol (SNMP), enabling third-party applications to communicate with the Intelligent Agent and be managed along with Oracle targets.

The Intelligent Agent handles the collection of system performance data (for example, file I/O or CPU usage data) for Capacity Planner and Performance Manager, which are data-analysis applications in the optional Oracle Diagnostics Pack, Oracle Management Pack for Oracle Applications, and Oracle Management Pack for SAP R/3. You do not have to configure a separate data collection service for this purpose.


For more information about the Intelligent Agent, see the Oracle Intelligent Agent Users Guide. The optional management packs are available as part of the Oracle9i Database Server software.

Benefits of Oracle Enterprise Manager

Oracle Enterprise Manager enables administrators to maintain the highest level of performance and availability while controlling system management costs. This section describes the major benefits of Oracle Enterprise Manager and its scalability, power, and reliability.

Topic See Page

Single Point of Management


Multi-Administrator System


Scalability for Growing, Distributed Environments


Extensible Architecture


Automated Lights-out Administration


Autonomous Intelligent Agent


Database Administration Functionality


Ease of Use


Single Point of Management

From the Oracle Enterprise Manager Console, you can manage and administer all your distributed systems, databases, tools, and users from a central location. An intuitive graphical user interface that provides powerful and robust system management, the Console gives you a central point of control for the Oracle environment. The easy-to-use interface can simplify tasks for the system administrator.

With Oracle Enterprise Manager, a distributed enterprise can be managed as easily and effectively as a local workgroup, lowering the cost of system ownership. The Oracle Enterprise Manager framework allows the automation and delegation of routine, time-consuming tasks on multiple targets. Jobs can be scheduled on multiple nodes simultaneously and groups of targets can be monitored together.

Multi-Administrator System

In many enterprises, teams of database administrators must cooperate to manage numerous systems, often remotely. With Oracle Enterprise Manager, database management tasks can be organized and distributed in multi-administrator enterprises, and system data can be safely shared among administrators.

With Oracle Enterprise Manager, system data, application data, and the state of managed targets is contained in the repository, which stores all administrative data. If you are using more than one Oracle Management Server, they can share a repository. The Oracle Management Server handles security and distributes notifications and management information to administrators based on the access levels that are set up for them in the repository. Each administrator has an account which provides access to the Oracle Management Server and the central data stored in the repository.

The Oracle Management Server filters information as it flows between different consoles and the targets on the managed nodes. Because all administrative data is stored in a central repository, administrators can work together and see the activity of other administrators. This distribution of information reduces redundancy, which saves time and keeps administrative costs down.

Scalability for Growing, Distributed Environments

With its three-tier architecture, Oracle Enterprise Manager has the ability to maintain performance and automate routine tasks in rapidly growing, distributed environments. As the number of nodes and managed targets in your network increases, or if the current Oracle Management Server is overloaded, you can add more Oracle Management Servers to the middle tier to share and balance the workload. Balancing the workload in the middle tier rather than investing in additional systems management overhead, controls the cost of systems management.

Because multiple Oracle Management Servers can share a repository as their back-end store, they provide fault tolerance for each other. If one Oracle Management Server fails, the clients registered with it can immediately log in again and register with any of the other Oracle Management Servers running with that repository, and work continues seamlessly. Any clients registered with an Oracle Management Server other than the failed one are unaffected.

For failover and scalability of the repository database, Oracle has database solutions such as Oracle9i Real Application Clusters, Oracle Failsafe, Replication Management, and others.

Extensible Architecture

Oracle Enterprise Manager's flexible architecture allows new products and additional modules to be written and added to the suite. Oracle Enterprise Manager's use of open standards (CORBA, IIOP, etc.) makes it possible to integrate third-party tools into the Console.

Automated Lights-out Administration

In a large, distributed database environment, the proportion of managed nodes per administrator increases rapidly, requiring tools that can automate tasks. Oracle Enterprise Manager offers automated, "lights-out" task management and proactive target monitoring for events, which enables control of the enterprise without necessarily needing additional staff to meet increasing system responsibilities.

Using the Job System, you can automate routine tasks such as database backups or running reports on a regular basis. Using the Event System, you can have remote databases and other targets monitored for important occurrences (events) and set up "fixit" jobs that automatically execute in response to events. Monitoring of targets for occurrences and automatic problem correction ensures that problems are dealt with before they noticeably impact end users.

Autonomous Intelligent Agent

Because jobs are executed locally at the managed nodes, they can be completed even when a crucial part of the network is down. Localized tasks are dependable because all jobs are processed by the Intelligent Agents on the individual managed nodes.

For example, if you schedule a job to run on a node, the job will be executed locally at the node at the specified time, and will run even if a network outage occurs between the node, the Oracle Management Server, and the Console. If a target on the node is down, the Intelligent Agent stores any jobs to be performed on the target until the target is back up. If the Console is down, the Intelligent Agent stores any information about the status of the job until the Console is back in service and can receive information.

Database Administration Functionality

Oracle Database Administrators (DBAs) are commonly required to perform tasks such as creating users, performing backups, adding tablespaces or datafiles, managing database objects, and changing instance parameters.

The Oracle Enterprise Manager Console offers database administration functionality that help automate and simplify the daily tasks of a DBA:


For an overview of the database administration functionality, see Chapter 4, "Database Administration" or the Oracle Enterprise Manager online help.

Ease of Use

Oracle Enterprise Manager provides a complete user-friendly system management solution that allows administrators to manage distributed environments with a minimum of effort. With the ability to access and manage remote targets, an administrator can more easily make changes and execute commands. The Oracle Enterprise Manager framework is designed to offer high scalability without increasing complexity, allowing an administrator to manage more and more targets, confident that the environment is under control.

In addition, all Oracle Enterprise Manager applications have a similar graphical user interface allowing the administrator to manage the Oracle enterprise using the same familiar front end with each application. This interface can be used by both beginning and advanced users, and also can serve as a training tool when used with the Oracle Enterprise Manager wizards and quick tours.

Common Services

Oracle Enterprise Manager is made up of common services that help you manage the Oracle environment.

These common services include:

Target Discovery

When you launch the Console with a Management Server connection, you have access to a Discovery Wizard. This wizard is used to identify nodes in your environment that you want to manage with Enterprise Manager. In order for a node to be automatically discovered, an Intelligent Agent must be running on the node. When discovered, the node and any supported targets installed on that node are added to the Console Navigator tree and stored in the repository.

Job System

The Job System enables the automation of standard and repetitive administrative tasks. With the Job System, you can create and manage jobs, schedule their execution, and view and share information about defined jobs with other administrators connected to the repository.

In-place modification also allows administrators to add and/or remove targets for submitted jobs, regardless of the version of the Intelligent Agent.

Upon job completion or failure, the system can be configured to automatically notify you and/or other administrators through Console alert, e-mail, or page, depending on the access levels and preferred credentials.

Because a job is an administrative entity (object) within the Oracle Enterprise Manager framework, an owner is always specified for the job as well as basic security parameters, which prevent or allow viewing and modifications by other administrators.


For more information about the Job System, see Chapter 3, "Job and Event Systems".

Event System

The Event System allows the Oracle environment to be monitored for operational occurrences and borderline conditions such as loss of service, shortage of storage, and resource problems such as high CPU usage.


Only up/down events are shipped with base Oracle Enterprise Manager; all other more advanced events are bundled with the separately licensable packs.

These critical occurrences, called "events", are each made up of one or more "tests" which an Intelligent Agent makes towards a managed target when an event is registered against it. When you register an event through the Console, you define the event condition by selecting one or more tests.

You can also dynamically change parameters of a registered event by selecting a registered event, adding and/or removing targets, changing some attributes, and then applying the changes to all the targets of that event. For 9i, you can perform a full modification. For pre-9i, you can perform limited modification. For information on Intelligent Agent restrictions, refer to the Oracle Enterprise Manager Administrator's Guide.

In Oracle9i, you can also specify custom operating system scripts as new event tests that will be included as part of the Enterprise Manager events system. User-Defined Events expands the breadth and flexibility of the events system by allowing you to write and incorporate custom scripts that are particular to your environment. Also, you can tie in your existing monitoring scripts into the events system, and thus take advantage of the services provided by the Enterprise Manager framework: paging/e-mail notifications for events that go in alarm, and collaborative administration of targets.

In the Event system, you have the flexibility to schedule the evaluation of an event at specified intervals, on specified day of the week, or on a specified day of the month. It is a useful feature since you can schedule resource intensive jobs during off-peak periods.

When an event occurs and is detected by an Intelligent Agent, specified administrators are notified by Console alert, e-mail, or page, depending on their access levels and preferred credentials. You can also set up a "fixit" job to run automatically in response to an event.

As in the Job System, you can share event information with other administrators connected to the repository. Events are also objects within the Oracle Enterprise Manager framework and are assigned owners and security parameters.


For more information about the Event System, see Chapter 3, "Job and Event Systems".

Notification System and Filtering

Administrators can be notified of the status of jobs and events by Console alert, e-mail, or page. When scheduling a job or registering an event, you set up notification procedures and choose which administrators to have notified of job completion or failure or event occurrence. Notification filters allow each administrator to specify when to send an email notification as opposed to a page notification as a result of a job or event status change.

Paging/E-mail Blackouts

Oracle Enterprise Manager has a paging and e-mail blackout feature, which prevents administrators from being flooded with e-mails and pages if a managed target is brought down. For example, if a target is brought down on a regular basis for scheduled maintenance, you can specify paging and e-mail "blackouts" for the targets during those periods. During a specified blackout, enhanced notification (paging/e-mail) is deactivated while the target is down. You also have the options to start and stop blackout periods and show a list of existing blackout periods. Blackout periods can be set indefinitely until stopped, or you can specify a duration (days:hours:minutes) for a blackout period.


Security parameters in Oracle Enterprise Manager are defined for targets, objects, and administrators. All administrator accounts are defined by a Super Administrator who creates and defines the access levels of all Enterprise Manager administrators. A Super Administrator can access any object and control its security parameters, including objects owned by other administrators. Security parameters are set up in the Preferences dialog box, shown in Figure 1-7, "Preferences Dialog Box".

Figure 1-7 Preferences Dialog Box

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Oracle Enterprise Manager's restricted access to target discovery provides better security of managed systems by allowing only Super Administrators to discover, refresh, and remove targets from the Enterprise Manager Console. This functionality prevents novice or new administrators of a team from adding or deleting targets for which they are not responsible.

The Console improves the security of managed environments by allowing Administrators who are actually responsible for specific targets to view and manipulate only those targets. This feature allows Super Administrators to control and customize the list of managed targets displayed in the Consoles of other, regular Administrators using Enterprise Manager. In addition, restricting certain targets from Administrators' views improves Administrators' ability to manage the targets to which they do have access. For example, rather than viewing all 300 discovered databases in his Console Navigator tree, Administrator Fred's Super Administrator can customize Fred's view such that only the 20 databases he is responsible for appear.

Comprehensive Reporting

Enterprise Manager provides comprehensive reporting so that administrators can quickly access information about the status of all monitored systems in their enterprise. The reporting functionality is fully integrated with the Enterprise Manager Job system, allowing reports to be generated automatically at specific times or at regular intervals.

This functionality, which is central to all Enterprise Manager applications, allows Administrators to create user-defined reports to satisfy unique business needs, publish reports to a central web site for general viewing, and to specify whether published reports should be generated on demand for constant access to up-to-date information or on a specified schedule to run time-consuming and/or CPU-intensive reports during non-peak hours.

A rich set of predefined reports are supplied with Enterprise Manager out of the box such as:

For more information, see the Oracle Enterprise Manager Administrator's Guide and the online help.


More reports may be available depending on the Enterprise Manager options you have installed.

Font Control

You can control font size and style of the Console and applications. If the default fonts are too large or small for your display, you can change them from the Console. Any application which is then launched from the Console will display the updated font size.

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