Introduction to Oracle Enterprise Manager 11g
November 10, 2010
Learn what's new in Oracle Enterprise Manager 11g, and how you will benefit by learning to use it.
For home use and learning purposes, it’s very common to create a new Oracle database using the Database Configuration Assistant (DBCA). Along the way, one of the screens in Oracle Universal Installer presents you with an option to configure Enterprise Manager.
The options shown in Figure 1 are typical: you’re going to get Database Control configured at the end, and the Enterprise Manager configuration is pretty much blown off. So, what does it take to configure Enterprise Manager? A disabled item on the DBCA window indicates that no management service agent was found, and that is a key piece in getting DBCA to recognize that Enterprise Manager is even a possibility. However, before that can even take place, there is a good bit of setup outside of DBCA done beforehand.
Without an agent, what you get with a single database is the Database Control version of Enterprise Manager. The repository for what is collected data-wise in EM is the database you just created, and the schema or owner is SYSMAN. With an agent (along with other components external to the database), your new database can be managed by Enterprise Manager and the repository can live elsewhere. In this case, Database Control graduates to Grid Control. The illustration below shows the architecture you’re likely to encounter in a basic setup.
What’s different from a local management/Database Control installation are the presence of the Oracle Management Service (OMS) and the Management Agent. Moreover, instead of seeing Database Control in the web browser/user interface, you see Grid Control. What’s not new or different – with a caveat - is the Management Repository. When using Enterprise Manager/Database Control, the repository is installed within the database being created. When using Enterprise Manager/Grid Control, the repository can live just about anywhere in terms of being within another Oracle database.
The first step in an installation is to create the management repository. That’s pretty straightforward (and will be covered later), and isn’t too different from what you may be used to when using “emca” to create or recreate a repository. The second step is to install an Oracle WebLogic Server for the management service, and the final step is to install a complete Enterprise Manager system including an agent and an OMS.
What is definitely new for OEM release 11g is the incorporation of Oracle WebLogic Server (WLS). BEA Systems was the prior owner of WLS. WLS has the distinction of being the first standards based Java application server. For what it’s worth, WLS used to operate via a license key, and your accessible features were driven or controlled by this file. BEA had an online license key migration feature whereby you could get a new key for a new server (e.g., if you wanted to migrate an application from one server to another, hardware replacement, and so on).
With Oracle Corporation having acquired BEA, that license key migration process is dead and gone, so if you have an existing WLS installation, your upgrade path is going to include licensing of WLS from Oracle.
Yet another key aspect of Oracle using WebLogic Server can be found in application management. WLS is the key to Fusion Middleware, and in this context, is THE web server going forward. There are other products where you still have a choice in terms of which J2EE compliant application server you can use. APEX, as an example, offers several choices, but by and large, it appears all roads (with respect to web servers supporting Oracle products) lead to WLS.
What we know as Enterprise Manager/Grid Control today – with its user interface and how it can help you centrally manage one or more Oracle databases – will become (and is in the process of becoming elsewhere) the web management interface for not only databases, but for many other Oracle products. Put another way, any product related to Fusion is going to be managed via Oracle Enterprise Manager. According to an Oracle whitepaper, the technology stack is going to offer “a complete end to end monitoring and management solution across the entire spectrum of business transactions, with the ability to diagnose and remediate any problems at all tiers of the application stack.”
What’s in it for you to learn how to install and use the Grid Control version of Enterprise Manager? There are several benefits, each with excellent payoff in terms of making you more valuable. First, getting smart on Enterprise Manager Grid Control has payoff in terms of being able to manage multiple databases from one interface. The idea or concept of installing an agent, which is used to monitor and report to a centralized management server, is used in quite a few other products outside the world of Oracle. If you have experience with any of these other products, you’ll feel right at home with Oracle’s version of this. There is a slight to negligible hit on performance due to the presence of the agent, but that’s not any different than running Database Control. If you are comfortable with the overhead of AWR on a local database, you won’t mind the presence of an agent.
Second, and probably the biggest reason to get on board with Grid Control, is the exposure you’re going to get with WebLogic Server. Oracle Application Server and Oracle HTTP Server, let’s say, served their purpose back in the day, but now we have something better and more robust. In several industry reports (going back several years before the acquisition by Oracle), WLS was the leading application server. Getting exposure to a major league product can’t be a bad thing.
Third, and finally, given the statement of direction in the white paper, a lot of what you know in the Grid Control/database management arena is going to carry over into your ability to manage Oracle Fusion Middleware products. Already being familiar with the user interface/look-and-feel of Oracle’s web-based management tools will save you time and energy. You can take what you know from installing and configuring WLS on the database side and immediately apply that experience against configuring and managing other products or tools (Forms and Reports, E-Business Suite’s Oracle Application Manager, etc.).
In the next article, I’ll cover the installation of Enterprise Manager and demonstrate how to use and configure agents for databases installed on a Windows 2003 server and on a server using Oracle Enterprise Linux (both of which will run as virtual machines on the same computer).