2.1. The Oracle Enterprise Management Framework
While computer systems have been growing larger and more complex, IT organizations have been performing an increasing number of tasks with the same or fewer resources. This is especially true of the DBA. Traditionally, you have spent most of your time creating databases and objects, managing space, and monitoring performance. Today, you need to take care of these tasks in less time and more effectively in order to meet other IT needs and challenges.
Businesses are becoming increasingly dependent on systems that must be available around the clock. You must constantly monitor these mission-critical operations, and you need to know when the system is not functioning correctly or is not available for use. You need to be able to answer questions quickly about the performance and availability of the components that constitute an Oracle enterprise. The Oracle management framework is designed to meet these needs and challenges.
The Oracle Enterprise Management Framework provides a comprehensive set of integrated tools that you can use to perform your traditional tasks more easily and efficiently as well as effectively monitor the components in the enterprise. You can customize this framework and use it to manage your applications via a web-based interface. Having this type of tool is vital if you manage larger and more complex databases, especially if they are spread over disparate geographic regions.
You can extend the management framework using the software developer's kit (SDK). The extensions give you flexibility in monitoring organizational components. For example, you can quickly define new target types to allow users to collect monitoring information from managed targets specific to their enterprise environment. Figure 2.1 provides an overview of management framework components.
All communication between the targets of the Oracle Enterprise Management Framework is orchestrated by Oracle Management Agents. Management Agents are responsible for identifying and collecting data about the entities of interest within the Management Framework. For example, agents can monitor an Oracle database and send out an alert if the database is not available. Normally, one Oracle Management Agent is on each of the host systems that you are interested in monitoring via the Oracle Enterprise Management Framework. The agents store the data collected about the managed targets in the Management Repository.
The Oracle Enterprise Management Framework is divided into these functional areas:
Managed Targets You administer managed targets using the Enterprise Manager. Examples of managed targets include databases, application servers, web servers, applications, and Oracle agents such as the Oracle Net listener and Connection Manager. You can add and remove managed targets as the needs of the enterprise change. Many managed targets are preconfigured to function and communicate with the Oracle Enterprise Management Framework.
Management Service The Oracle Management Service is a Java-based web component that is the actual interface you use to monitor and control managed targets within the Management Framework.
Figure 2.1. Oracle Enterprise Management Framework components
Oracle Management Repository Configuration and monitoring information collected about the managed targets is stored in an Oracle Management Repository. The repository comprises two tablespaces in an Oracle database that contain information about administrators, targets, and applications that are managed within Enterprise Manager.
The Management Agents communicate with the Management Service to place data into the repository. The Management Repository is organized for easy retrieval and display within the Oracle Management Service.
Oracle Enterprise Manager 10g Grid Control Enterprises that must manage many databases, application servers, web servers, and other components can use the Enterprise Manager Grid Control. The EM Grid Control is a web-based user interface that communicates with and centrally manages all the components within the Oracle enterprise.
You can use the EM Grid Control to monitor and administer the entire computing environment from a centralized location, including hosts, databases, listeners, application servers, HTTP servers, and web applications.
Oracle Enterprise Manager 10g Database Control The EM Database Control is a webbased component of the Enterprise Management Framework for managing Oracle Database 10g Release 1 (10.1). The Enterprise Manager 10g Database Control allows you to monitor and administer a single Oracle database instance or a single Real Application Cluster (RAC) environment.
Application Server Control The Application Server Control is a web-based component of Enterprise Manager that monitors the Oracle Application Server 10g (9.0.4). The Application Server Control allows you to monitor and administer a single Oracle Application Server instance, a collection of Oracle Application Server instances, or Oracle Application Server Clusters.
Now that you have an undertanding of the components that comprise the Oracle Enterprise Management Framework, let's discuss how to control and access the various components within the framework.
In the following sections, we will explore how to stop and start the Oracle Management Agent. We will also explain how to start and use the i SQL*Plus tool.
2.1.1. Starting and Stopping the Oracle Management Agent
As we discussed in the previous section, if you elect to use the Oracle Enterprise Management Framework, there are two methods of administering your databases within the enterprise. You can centrally administer all of your databases using the Oracle Enterprise Manager 10g Grid Control or you can manage each database individually using the Oracle Enterprise Manager 10g Database Control. In either case, you need to understand how to stop and start the necessary agents to use these tools.
If you are centrally managing all your Oracle databases via Oracle Enterprise Manager Grid Control Framework, you need to start an agent process on each managed target server that you want available to the framework.
An Oracle management agent is a background process that runs on each managed target server. The agent collects information about the managed target and then communicates with the central management service, which maintains the information about the managed target.
You use the EMCTL command-line utility to start and stop the Oracle management agent. To start the agent, use the emctl start agent command. Here is an example:
/u01/app/oracle/product/10.0.1/bin> emctl start agent Oracle Enterprise Manager 10g Database Control Release 10.1.0.2.0 Copyright © 2002, 2004 Oracle Corporation, All rights reserved Start agent. . . . .started.
Once the agent starts, you can manage the target using the Oracle Enterprise Manager Grid Control.
To stop the agent, use the emctl stop agent command. Here is an example of using the command:
/u01/app/oracle/product/10.0.1/bin> emctl stop agent
Oracle Enterprise Manager 10g Database Control Release 10.1.0.2.0
Copyright © 2002, 2004 Oracle Corporation, All rights reserved
This will stop the Oracle Enterprise Manager 10g Database Control process.
Contuinue [y/n] :y
Enter Management Password :
Stopping Oracle Enterprise Manager 10g Database Control . . . . Stopped
Agent is not running.If you are going to manage your databases as separate entities and not within the centralized Grid Control framework, you can use the Enterprise Manager Database Control web tool. To start the Database Control Agent, which is similar to the Grid Control process, issue the emctl start dbconsole command. In a Unix environment, the emctl program can be found in your ORACLE_ HOME/bin directory. In the following examples, /u01/app/oracle/product/10.0.1/bin refers to the ORACLE_HOME directory where the emctl program is located.
Here is an example of issuing the emctl start dbconsole command:
/u01/app/oracle/product/10.0.1/bin> emctl start dbconsole TZ set to US/Central Oracle Enterprise Manager 10.0.1.0.0 Copyright © 2002, 2004 Oracle Corporation, All rights reserved http://10.19.200.50:5500/em/cosole/aboutApplication http://10.19.200.50:/emd/console/aboutApplication Starting DB Console. . . . . . . . . . started.
To stop the Database Control agent, use the emctl stop dbconsole as follows:
/u01/app/oracle/product/10.0.1/bin> emctl stop dbconsole TZ set to US/Central
Oracle Enterprise Manager 10.0.1.0.0 Copyright © 2002, 2004 Oracle Corporation, All rights reserved http://10.19.200.50:5500/em/cosole/aboutApplication http://10.19.200.50:/emd/console/aboutApplication Enter Management password: Stopping dbconsole. . . . . . Stopped.
You can also view the status of the agent by issuing the emctl status dbconsole command:
/u01/app/oracle/product/10.0.1/bin> emctl status dbconsole E:>emctl status dbconsole Oracle Enterprise Manager 10g Database Control Release 10.1.0.2.0 Copyright (c) 1996, 2004 Oracle Corporation. All rights reserved. http://Ldn6f751-mw.corp.goxroads.net:5500/em/console/aboutApplication Oracle Enterprise Manager 10g is not running. ------------------------------------------------------------------ Logs are generated in directory E:oracleproduct10.1.0Db_1/Ldn6f751- mw.corp.goxroads.net_ORCL/sysman/log
In this example, the agent is not running. You can view information about the status of the agent in the log files that are created. In this example, you see the location of the logs listed. You can access and view the logs with any text editor.
2.1.2. Accessing a Database Using the Database Control
After you start the Database Control agent, you can access the web-based tool. To do so, open your web browser and enter the URL as shown below. Note that port 5500 is the default port.
http://hostname:portnumber/em
If your database is open, you will see the Database Control Login screen, as shown in Figure 2.2.
To log in, enter a user ID and a password. When your database is first created, the initial login user ID will most likely be SYS, SYSTEM, or SYSMAN. Once you are connected to the database via Database Control, you can perform a variety of administrative tasks from the console.
2.1.3. Using iSql*Plus
Oracle provides a web-based version of the SQL*Plus tool called i SQL*Plus.i SQL*Plus has a server-side listener process that must be started in order for clients to connect to a database through the browser interface. To start the listener process on a Windows server, run the following command:
%ORACLE_HOME%inisqlplusctl start
Figure 2.2. The Database Control Login screen
D:oracleproduct10.1.0Db_1BIN> isqlplusctl start iSQL*Plus 10.1.0.2.0 Copyright (c) 2004 Oracle. All rights reserved. Starting iSQL*Plus ... iSQL*Plus started.
To start the iSQL*Plus listener process on a Unix server, run the following command:
$ORACLE_HOME/bin/isqlplusctl start
NOTE
If you are working in a Windows environment, you can also start the serverside listener process by starting the iSQL*Plus Application Server service.
iSQL*Plus uses the default port number 5560 for the server-side listener process. To stop the iSQL*Plus listener process on a Unix server, run the following command:
$ORACLE_HOME/bin/> isqlplusctl stop iSQL*Plus 10.1.0.2.0 Copyright (c) 2004 Oracle. All rights reserved. Stopping iSQL*Plus ... iSQL*Plus stopped. $ORACLE_HOME/bin/>
After you start the process, you can access iSQL*Plus by entering the following URL in your web browser. Note that the default port number is 5560.
http://machine_name.domain_name:port/iSQLplus
You will be presented with a login screen like the one in Figure 2.3.
Figure 2.3. The iSQL*Plus Login screen
When you are logged in to the iSQL*Plus tool, you can run commands and load and save scripts much the same as you can using SQL*Plus. Enter one or more commands in the Workspace box and click the Execute button. If you enter multiple commands in this box, Oracle runs each command in order. Any output is displayed in a results panel at the bottom of the screen when the query is complete.
To view a summary of your last 10 commands, click the History tab. You can change the number of queries stored in history by clicking the Preferences icon and modifying History Size.
You can also describe table structures within iSQL*Plus. Run the DESCRIBE command to display a description of a database object. For example, if you describe a table, you will see a summary of the table columns, datatypes, and column sizes in the results window. Figure 2.4 shows an example of describing a table.
NOTE
It is possible to set up iSQL*Plus to allow connections to the database with SYSOPER or SYSDBA privileges. To allow this type of connection, the user must be authenticated by the iSQL*Plus application server. You must perform a number of steps to set up the authentication. For a complete summary of these steps, refer to "Database Storage and Schema" in the section "Enabling iSQL*Plus DBA Access" in SQL*Plus Users Guide and Reference Release 10.1 (Part Number B12170-01).
Now that you have an understanding of the Oracle Enterprise Management Framework and some of the tools provided within the framework, we will explore how to create a database using the Database Configuration Assistant.
Figure 2.4. The iSQL*Plus query results screen
