Chapter 2: Architecture for Virtualization with WebSphere Application Server, V5

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Overview

Executive summary: In today's information technology (IT) operating environment, resources are underused and applications cost too much and take too long to deploy and manage. An on-demand operating environment addresses these issues. The on-demand operating environment is virtualized, autonomic, integrated, and based on open standards.

Virtualization enables a collection of computing resources to be shared and managed as if they were one large virtual resource. A virtualized environment makes the most efficient use of its resources by sharing resources and providing what is needed only when it is needed. Not only are resources highly used, excess capacity can easily be used for new or unexpected needs.

This chapter explores the topic of a virtualized application server environment. Virtualizing application servers leads to a shared environment that increases server use. However, there are many challenges. Applications can interfere with each other without the proper isolation techniques. System administration costs can increase due to the complexity of managing the capacity of shared servers. With the proper architectural considerations for isolation and clustering, WebSphere Application Server, Version 5 can help with virtualization and get you on your way to an on-demand operating environment.

In customer engagements exploring the capabilities of WebSphere Application Server, Version 5, the High-Volume Web Sites (HVWS) organization developed and tested several virtualization architectures for application isolation, failover and high availability, and system administration. This chapter reviews these configurations, suggests where their use is recommended, and specifies the trade-offs that must be considered. It also introduces how features of the IBM pSeries platform, such as logical partitioning (LPAR), can help with isolation and managing capacity in a virtualized application server environment.

You can start your journey today to the on-demand operating environment by using WebSphere Application Server, Version 5 to virtualize your application servers. It's the right first step to prepare you for a successful future implementation of emerging on-demand offerings such as IBM Server Allocation for WebSphere Application Server.

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