Product architecture

Product subsystems WebSphere applications WebSphere applications
Servers

Environment

System administration

Performance

Troubleshooting

Services

J2EE applications

Clients

Web services

J2EE resources

WebSphere extensions

For the most part, the subsystems listed previously do not depend on the type of applications being deployed.

 

Servers

Application servers. An application server is a Java virtual machine (JVM) running user applications. Application servers use Java technology to extend Web server capabilities to handle Web application requests. An application server makes it possible for a server to generate a dynamic, customized response to a client request. The WAS product provides application servers.

For more introduction, refer to Introduction: Application servers.

Generic servers. In distributed platforms, use the generic servers feature to create a generic server as an application server instance within the product administration, and associate it with a non-WebSphere server or process. The generic server can be associated with any server or process that is necessary to support the application server environment.

For more information, refer to Server collection.

JMS servers. The product supports messaging by providing a Java Message Service Provider that conforms to the JMS Specification 1.1. On the single-server product, the JMS functions (of the JMS provider) for an application server are served by the JMS server within the application server.

In the Network Deployment product, the JMS functions (of JMS providers) within the administrative domain are served by one or more JMS servers.

For more information, refer to Learning about messaging with WAS.

Web servers. In the WAS product, an application server works with a Web server to handle requests for Web applications. The application server and Web server communicate using an HTTP plug-in for the Web server.

For more information, refer to Communicating with Web servers.

Core groups and core group bridges. A core group is a statically defined component of the high availability manager. The high availability manager is a product function that monitors the application server environment and provides peer-to-peer failover of application server components. A core group bridge is a configurable service for communication between core groups.

For more information, refer to Core groups.

Clusters. In the Network Deployment product, clusters and cluster members help you monitor application servers and manage the workloads of servers.

For more information, refer to Balancing workloads with clusters.

 

Environment settings

Cell-wide settings help handle requests among Web applications, Web containers, and application servers in a logical administrative domain called a cell.

Virtual hosts.

A virtual host is a configuration enabling a single host machine to resemble multiple host machines. Resources that are associated with one virtual host cannot share data with resources associated with another virtual host, even if the virtual hosts share the same physical machine. Each virtual host has a logical name and a list of one or more DNS aliases by which it is known. A DNS alias is the TCP/IP host name and port number that are used to request the servlet, for example: hostname:80.

WebSphere variables.

Variables are used to control settings and properties relating to the server environment. WebSphere variables are used to configure product path names such as JAVA_HOME, cell-wide customization values, and the WAS for z/OS location service.

Shared library files Shared libraries are files used by multiple applications. You can define a shared library at the cell, node, or server level. You can then associate the library to an application or server in order for the classes represented by the shared library to be loaded in either a server-wide or application-specific class loader.

Replication domains. Replication is a service that transfers data, objects, or events among application servers. Data replication service (DRS) is the internal WAS component that replicates data. Replication domains transfer data, objects, or events for session manager, dynamic cache, or stateful session beans among application servers in a cluster.

For more information, refer to Replication.

 

System administration

Administrative console

The administrative console is a graphical interface that provides many features to guide you through deployment and systems administration tasks. Use it to explore available management options.

Scripting client (wsadmin). The WebSphere administrative (wsadmin) scripting program is a powerful, non-graphical command interpreter environment enabling you to run administrative operations in a scripting language. You can also submit scripting language programs to run. The wsadmin tool is intended for production environments and unattended operations.

For more introduction, refer to Introduction: Administrative scripting (wsadmin).

Administrative programs (Java Management Extensions). The product supports a Java programming interface for developing administrative programs. All of the administrative tools that are supplied with the product are written according to the API, which is based on the industry standard Java Management Extensions (JMX) specification.

For more introduction, refer to Introduction: Administrative programs.

Command line tools. Command-line tools are simple programs that you run from an operating system command-line prompt to perform specific tasks, as opposed to general purpose administration. Using the tools, one can start and stop application servers, check server status, add or remove nodes, and complete similar tasks.

For more introduction, refer to Introduction: Administrative commands.

Configuration files

Product configuration data resides in XML files that are manipulated by the previously mentioned administrative clients.

Domains (cells, nodes).

Servers, nodes and node agents, cells, and the deployment manager are fundamental concepts in the administrative universe of the product. It is also important to understand the various processes in the administrative topology and the operating environment in which they apply.

 

Performance Monitoring tools.

Performance monitoring is an activity in which you collect and analyze data about the performance of your applications and their environments. Performance monitoring tools include :

Tuning tools. Tuning the product helps you obtain the best performance from your Web site. Tuning the product involves analyzing performance data and determining the optimal server configuration. This determination requires considerable knowledge about the various components in the application server and their performance characteristics. The performance advisors encapsulate this knowledge, analyze the performance data and provide configuration recommendations to improve the application server performance. Therefore, the performance advisors provide a starting point to the application server tuning process and help you without requiring that you become an expert.

For more information, refer to Obtaining performance advice from the performance advisors.

 

Troubleshoot

Diagnostic tools. Diagnostic tools help you isolate the source of problems. Many diagnostic tools are available for this product.

Support and self-help IBM Support can assist in deciphering the output of diagnostic tools. Refer to the WAS Technical Support Web site for current information on known problems and their resolution. Documents at this site can save you time gathering information that is needed to resolve a problem.

 

See also


Three-tier architectures

 

See Also


WebSphere applications: Overview and new features

 



 

 

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