Oracle WebLogic Server – An Overview

Oracle WebLogic Server is a scalable, enterprise-ready Java Platform, Enterprise Edition (Java EE) application server. The WebLogic Server infrastructure supports the deployment of many types of distributed applications and is an ideal foundation for building applications based on Service Oriented Architectures (SOA).
 
Oracle WebLogic Server 11g is a component of Oracle Fusion Middleware 11g, which consists of several Oracle products that span business intelligence, collaboration tools, content management, and integration services. The underlying application server supporting these middleware applications is Oracle WebLogic Server 11g. Products such as Oracle SOA Suite and Oracle Fusion applications rely on Oracle WebLogic Server 11g to run their code.
Oracle offers three distinct products as part of the Oracle WebLogic Server 11g application family:

  • Oracle WebLogic Server Standard Edition (SE)
  • Oracle WebLogic Server Enterprise Edition (EE)
  • Oracle WebLogic Suite

Oracle WebLogic 11g Server Standard Edition
The WebLogic Server Standard Edition (SE) is a full-featured server, but is mainly intended for
developers to develop enterprise applications quickly. WebLogic Server SE implements all the
Java EE standards and offers management capabilities through the Administration Console.
Oracle WebLogic 11g Server Enterprise Edition
Oracle WebLogic Server EE is designed for mission-critical applications that require high
availability and advanced diagnostic capabilities. The EE version contains all the features of the
SE version, of course, but in addition supports clustering of servers for high availability and the
ability to manage multiple domains, plus various diagnostic tools.
Oracle WebLogic Suite 11g
Oracle WebLogic Suite offers support for dynamic scale-out applications with features such as
in-memory data grid technology and comprehensive management capabilities. It consists of the
following components:

  • Oracle WebLogic Server EE
  • Oracle Coherence (provides in-memory caching)
  • Oracle Top Link (provides persistence functionality)
  • Oracle JRockit (for low-latency, high-throughput transactions)
  • Enterprise Manager (Admin & Operations)
  • Development Tools (jdeveloper/eclipse)


Oracle Weblogic Suite enhances application performance, improves application availability, and enables predictable and reliable application scalability with high quality of service. WebLogic Suite includes highly productive development tools based on Oracle JDeveloper and Oracle Enterprise pack for Eclipse, and a fully integrated management for large-scale administration and operations with Oracle Enterprise Manager. Taken together, the development, run time and management capabilities of WebLogic Suite provide the foundation for implementing mission-critical enterprise applications.

Oracle Weblogic 11g Server Administration Features

A brief overview of Oracle WebLogic Server features and describe how you can use them.

  • Weblogic Domain Structure
  • Administration Server
  • Managed Servers
  • High Availability
  • Diagnostic Framework
  • Security
  • Weblogic Domain Structure:

The basic administrative unit for a WebLogic Server 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 the minimum of one instance called the Administration
Server. The Administration Server is a central point of contact for server instances and system administration tools. A domain may also include additional WebLogic Server instances called Managed Servers.
The domain can run in two modes:
Development mode: A domain running in development mode does not require a password during startup of the Administration Server. You also can do autodeploy of your applications, as some other parameters are not that strictly configured.
Production mode: Running in production mode needs passwords, encryption of files at a higher level, and some parameters within the resources (such as JDBC, JMS) are strictly configured.
The next diagram shows the flow of the several steps creating a domain.

 

  • Administration Server:

A server is an instance of WebLogic Server that runs in its own JVM, and the Admin Server is a special instance of WebLogic Server designed for managing the domain rather than running applications. There is a one-to-one relationship between domains and the Admin Server an Admin Server belonging to Domain A can’t manage Domain B.
You can deploy applications on the Admin Server, but unless you’re operating in a purely developmental environment, use the Admin Server strictly for performing management tasks, not for deploying any applications. Although you can deploy applications on the Admin Server in a development environment, it’s a best practice not to do so in a production environment.

  • Managed Server:

Managed servers are the workhorses of WebLogic Server. Any additional servers you create after the creation of the default Admin Server are Managed Servers. The Managed Server contacts the Admin Server, only when you start it up, to get the configuration and deployment settings. For this reason, you should always start up the Admin Server before you start a Managed Server.
Once a Managed Server starts running, it operates completely independent of the Admin Server. Although you can deploy an application to the Admin Server itself, the recommended approach is to deploy applications to the Managed Servers. In a production environment, it’s common to run multiple Managed Servers as part of a cluster

  • High Availability:
  • WebLogic Server clusters provide scalability and reliability for your applications by distributing the workload among multiple instances of WebLogic Server. Incoming requests can be routed to a WebLogic Server instance in the cluster based on the volume of work being processed. In case of hardware or other failures, session state is available to other cluster nodes that can resume the workof the failed node.
  • Work Managers prioritize work based on rules you define and by monitoring actual run time performance statistics. This information is then used to optimize the performance of your application. Work Mangers may be applied globally to a WebLogic Server domain or to a specific application or component.
  • Overload protection gives WebLogic Server the ability to detect, avoid, and recover from overload conditions.
  • Network channels facilitate the effective use of network resources by segregating network traffic into channels based on the type of traffic.
  • Enterprise-ready deployment tools facilitate deployment and migration of applications from the development phase to a production environment.
  • Production redeployment enables enterprises to deploy a new version of their application without interrupting work in progress on the older version.
  • Diagnostic Framework

The WebLogic Diagnostic Framework is a monitoring and diagnostic service that lets you create, collect, analyze, archive, and access diagnostic data generated by a running server and its deployed applications. This data provides insight into the run-time performance of WebLogic Server instances and deployed applications and lets you isolate and diagnose faults and performance bottlenecks.

  • Security

The WebLogic Server security architecture provides a comprehensive, flexible security infrastructure designed to address the security challenges of making applications available on the Web. WebLogic security can be used standalone to secure WebLogic Server applications or as part of an enterprise-wide, security management system that represents a best-in-breed security management solution.

The c is replacing the g

As you can see, Oracle replaced the g in the release with c. It all had to do with where Oracle put their focus. The g stood for grid computing which Oracle introduced starting from release 10. Oracle’s grid computing product group includes (among other things) a database management system (DBMS) and an application server. In addition to supporting grid computing features such as resource sharing and automatic load balancing, 10g products automate many database management tasks. The Real Application Cluster (RAC) component makes it possible to install a database over multiple servers. Oracle has done a lot of effort to get ready for cloud computing, the c appears in the main release.



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