Before we move on to the description of each of the management areas within WebLogic, it is important to understand that the WebLogic Server software, which is used for the installation of the Oracle BI product suite, carries a limited license. Although the software itself is the full enterprise version—logically containing 100 percent of the product's functionality—the license that ships with Oracle BI 11g is not a full enterprise license for the WebLogic Server. This book hardly deals with software licensing, but here are a few nuances that one should keep in mind as they go about an Oracle BI 11g implementation:

These items are simply a few nuances of the product suite in relation to Oracle BI 11g. Most software products have a very short list of nuances like the preceding one. However, once you understand the nuances, it will be easier to ensure that you have a more successful implementation. It also allows your team to be prepared for implementations. Be sure to consult your Oracle sales representative to assist you with the licensing concerns.

The highest unit of management for controlling the WebLogic Server installation is called a domain. A domain is a logically related group of WebLogic Server resources that you manage as a unit. A domain always includes, and is centrally managed by, one Administration Server. Additional WebLogic Server instances which are controlled by the Administration Server for the domain are called Managed Servers. The configuration for all the servers in the domain is stored in the configuration repository, the config.xml file, which resides on the machine hosting the Administration Server. The config.xml files, by default, are stored in the path <FMW_HOME>\user_projects\domains\bifoundation_domain\ where <FMW_HOME> is the path on the server to which you have installed Oracle BI 11g.

Upon installing and configuring Oracle BI 11g, the domain named bifoundation_domain is established within the WebLogic Server. This domain is the recommended name for each Oracle BI 11g implementation and should not be modified.

The WebLogic Server is an enterprise software suite that manages a myriad of application server components mainly focused on Java technology. It is also comprised of many ancillary components that enable the software to scale well, and also make it a good choice for distributed environments and high availability.

Clearly, it is good enough to be at the core of Oracle Fusion Middleware. One of the most crucial components of the WebLogic Server is the WebLogic Administration Server. When installing the WebLogic Server software, the WebLogic Administration Server is automatically installed with it. It is the Administration Server that not only controls all subsequent WebLogic Server instances called Managed Servers, but also controls aspects such as security, Persistence Stores, and other application server-related configurations.

The WebLogic Server gets installed on the operating system and ultimately runs as a service on that machine. The WebLogic Server can be managed in several ways. The two main methods are via the Graphical User Interface (GUI) web application called the WebLogic Administration Console or via the command line using the WebLogic Scripting Tool (WLST). You can access the WebLogic Administration Console from any machine using a web-based client (that is, web browser) that can communicate with the WebLogic Administration Server through the network and/or firewall.

The WebLogic Administration Server and the WebLogic Server are basically synonymous. If the WebLogic Server is not running, the WebLogic Administration Console will be unavailable as well. If the WebLogic AdminServer is not running, no administrative tasks can be made to the system, although concessions are made for a High Availability configuration.

Web applications, Enterprise Java Beans (EJB), and other resources are deployed on to one or more WebLogic Managed Servers in a WebLogic Domain. A WebLogic Managed Server is an instance of a WebLogic Server in a WebLogic Server domain. Each WebLogic Server domain has at least one instance which acts as the WebLogic Administration Server which we have just discussed. Only one Administration Server per domain must exist, but one or more Managed Servers may exist in the WebLogic Server domain. Having one or more managed servers, allow for deployed JEE applications to be logically delineated. They also provide a means to independently configure application server port numbers and they provide a barrier for runtime issues such as a server crash. You can deploy applications, EJBs, and other resources on the WebLogic Managed Servers and use the WebLogic Administration Server only for configuration and management purposes.

In a production deployment, Oracle BI 11g is deployed into its own Managed Server. The Oracle BI 11g installer comes with three installation types—simple, enterprise, and software. The latter two installation types configure two WebLogic Server instances, the Administration Server and another Managed Server called bi_server1. Oracle BI 11g is deployed into the Managed Server called bi_server1 and is configured by default to resolve to port 9704. The simple installation type configures only the administration server, deploys Oracle BI 11g into it, and resolves to port 7001. For the simple installation type, only one WebLogic Server instance exists.

When administering the WebLogic Server via the Administration Console, the WebLogic Administration Server instance appears in the same list of servers that also includes the Managed Servers. The WebLogic Administration Server should be used only for configuration and management of the WebLogic Server and should not contain any additionally deployed applications, EJBs, and so on.

The general idea behind the Node Manager is that it takes on somewhat of a middle-man role. That is to say, the Node Manager provides a communication tunnel between the WebLogic Administration Server and any WebLogic Managed Servers configured within the WebLogic Domain. When the WebLogic Server environment is contained on a single physical server, it may be difficult to recognize the need for a Node Manager. However, its real power comes into play when Oracle BI 11g is scaled out horizontally on one or more physical servers. Each scaled-out deployment of WebLogic Server will contain a Node Manager. If the Node Manager is not running on the server on which the Managed Server is deployed, then the core Administration Server will not be able to issue start or stop commands to that server. As such, if the Node Manager is down, communication with the overall cluster will be affected.

The following diagram shows how machines A, B, and C are physically separated—each of them contains a Node Manager. You can see that the Administration Server communicates with the Node Managers and not directly to the Managed Servers:

We have briefly discussed the WebLogic Administration Console which controls the administrative configuration of the WebLogic Server Domain. This includes the components managed within it such as security, deployed applications, and so on. The other management tool which provides control on the deployed Oracle BI application ancillary deployments, libraries, and several other configurations is called the Enterprise Manager Fusion Middleware Control.

To discuss the vast amount of individual configuration points contained within the WebLogic Administration Console and Fusion Control, you can warrant an entire chapter devoted to this subject. In fact, a subsequent chapter, Chapter 5,Understanding the Systems Management Tools is dedicated to it.