The chapter discusses concepts and terminology relevant to each phase of the Java ES solution life cycle. The focus of this chapter is on deployment tasks, particularly deployment design and deployment implementation tasks.
The solution life cycle was introduced in Chapter 1, Introduction to Java Enterprise System as a standard approach to implementing business solutions using Java ES software. The life cycle diagram is repeated for easy reference.
Predeployment tasks are grouped into three phases, as shown in Figure 4–1:
Business analysis. Define the business goals of a proposed deployment effort and state the business requirements and constraints that must be met to achieve that goal.
Technical requirements. Use the results of the business analysis to create use cases that model user interaction with an anticipated software system. You also determine the usage patterns expected for those use cases. Using both the business analysis and the usage analysis, you formulate quality of service requirements (see Table 2–2) that the proposed deployment must meet.
Logical design. Analyze the use cases developed in the technical requirements phase to determine which Java ES infrastructure components and which custom-developed application components are needed to provide end-user services. Using the concepts discussed in Chapter 2, Java ES Solution Architectures, you design a logical architecture. The logical architecture shows all components and all interactions between components that are needed to effect the use cases of a particular software solution.
The logical architecture combined with performance, availability, security, and other quality of service requirements is encapsulated in a deployment scenario, as shown in the following figure. For more information about predeployment phases of the life cycle, see the Sun Java Enterprise System Deployment Planning Guide.
In the deployment phases of the life cycle, you translate a deployment scenario into a deployment design that you then implement, test, and roll out in a production environment.
The deployment process generally encompasses software components in all tiers and all infrastructure service levels required to support a software solution. In general, you must deploy both custom-developed application components (J2EE components, web services, or other servers) and the Java ES components needed to support the solution.
Deployment tasks are grouped into two phases, as shown in Figure 4–1:
Deployment Design. Deployment design depends on a solution’s logical architecture and on the performance, availability, security, scalability, serviceability, and other quality of service requirements a solution must meet. The quality of service dimension of deployment architecture plays a big role in the deployment design phase.
Deployment Implementation. Implementation of a deployment design is an iterative process that involves hardware setup, software installation and configuration, development and integration, testing, and other aspects of production rollout.
The following sections examine these two phases of the deployment process.
A deployment architecture is created by mapping the logical building blocks of an application (the logical architecture) to a physical computing environment in a way that meets the quality of service requirements specified in the deployment scenario. The deployment scenario is translated into a deployment architecture, as shown in the following figure.
One aspect of this architectural design is sizing the physical environment (determining the number of computers and estimating their processor power and RAM requirements) to meet performance, availability, security, and other quality of service requirements. Once the sizing is complete, you map Java ES components and application components to the various computers in the physical environment. The resulting deployment architecture must take into account the capabilities of different computers, characteristics of system infrastructure services, and restrictions on the total cost of ownership or total cost of availability.
The larger the number of Java ES components in the deployment scenario and the more demanding your quality of service requirements, the more demanding your design is on high-power computers and high network bandwidth. Where hardware is limited or prohibitively expensive, you might need to assess trade-offs between fixed costs (hardware) and variable costs (human resource requirements) or between different quality of service requirements, or you might have to increase the sophistication of your design.
The design of a deployment architecture often evolves in an iterative fashion. Reference deployment architectures serve as a starting point Java ES deployment design.
A reference architecture is based on a specific deployment scenario: a logical architecture with specific quality of service requirements. In the reference architecture, a software solution is deployed across a specific physical environment in a way that meets specified quality of service requirements. Performance testing at specified loads is based on the same set of use cases from which the deployment scenario was developed. Reference architecture documentation is available to Java ES customers under non-disclosure.
Based on a reference deployment architecture or a combination of reference architectures, you can design a first approximation of a deployment architecture that meets your own deployment scenario requirements. You can adjust the reference architectures or use them as reference points, taking into account the difference between your own deployment scenario and those upon which the reference architectures are based. In this way, you can assess the impact of your own sizing, performance, security, availability, capacity, and serviceability needs.
Implementation specifications provide details needed to implement a deployment architecture. The specifications generally include the following information:
Actual hardware, including computers, storage devices, load balancers, and network cabling
Network design, including subnets and security zones
Availability design details
Security design details
Implementation plans describe how you plan to perform the various tasks in the deployment implementation phase. The plans generally cover the following tasks:
Software installation, upgrade, and migration
System configuration and customization
Development and integration
Implementation of a deployment design consists of the tasks listed in the previous section and shown in Figure 4–1. The ordering of these tasks is not rigid because the deployment process is iterative in nature. The following subsections discuss each of the major deployment implementation tasks in the order in which they are typically performed.
The implementation specification includes all details of your physical environment: the computers, network design, network hardware (including cabling, switches, routers, and load balancers), storage devices, and so forth. All of this hardware needs to be set up as the platform that supports your Java ES solution.
The deployment architecture, along with additional details provided in implementation specifications, tells you which application components and which Java ES components are to reside on each computer in your physical environment. You use the Java ES integrated installer to install the appropriate Java ES components on each computer in your deployment architecture (see The Java ES Integrated Installer).
Your installation plan describes the sequence and scope of installer sessions. The approach you take to performing installation, however, might depend on whether you are performing a new installation of Java ES, whether you are upgrading previously installed Java ES components, or whether you are replacing third-party components with Java ES. The last two of these Java ES adoption scenarios often require you to migrate data or application code to achieve compatibility.
You must complete a number of system configuration tasks for the various system components to work together as an integrated system. First among these tasks is the initial configuration needed for each individual system component to start. Secondly, each Java ES component must be configured to communicate with those components with which it interacts.
High availability must also be configured, depending on your availability solution for each component. Users must be provisioned so they can access various services, and authentication and authorization policies and controls must be set up (see Integrated Identity and Security Services).
In most cases configuration tasks include some degree of customization of Java ES components to achieve the exact feature set you require. For example, you typically customize Portal Server to provide portal channels, Access Manager to perform authorization tasks, and so forth.
The logical architecture specified in the deployment scenario generally determines the scope of custom development work needed to implement a solution.
For some deployments, development might be quite extensive, requiring you to develop new business and presentation services from the beginning using J2EE components that run in an Application Server or Web Server environment. In such cases, you create a prototype of your solution and perform proof-of-concept testing before embarking on a full development effort.
For solutions that require extensive development, Sun JavaTM Studio software provides tools for programming distributed components or business services. Sun Java Studio developer tools simplify the programming and testing of applications supported by the Java ES infrastructure.
In some situations, Java ES components might be integrated with legacy applications or third-party services. These integrations might involve existing directories or data services in the data tier or existing components in the business services tier. Integrating Java ES components with these systems might require migrating data or application code.
The J2EE platform provides a connector framework that enables you to plug existing applications into the Application Server environment by developing J2EE resource adapters, and Message Queue provides a robust asynchronous messaging capability for integrating diverse applications.
Depending on the amount of customization or development work required, at some point you must verify your deployment architecture: you must test the solution against the use cases to verify that you can meet quality of service requirements.
If you have relatively few custom-developed services (a mostly out-of-the-box deployment), your solution might simply require customization of Java ES components and a pilot test of the system.
However, if you have developed significant new application logic and created custom services, this testing might be more extensive, involving prototype testing, integration testing, and so forth.
If this testing reveals shortcomings in your deployment architecture, you modify the architecture and test again. This iterative process should eventually result in a deployment architecture and implementation that is ready for deployment in a production environment.
Production rollout involves building out your deployment implementation in a production environment. This phase involves installing, configuring, and starting distributed applications and infrastructure services in a production environment, provisioning production system end users, setting up single sign-on and access policies, and so forth. You typically start with a limited deployment and move to organization-wide implementation. In this process, you perform trial runs in which you apply increasing loads to confirm that quality of service requirements are being met.
In the postdeployment stage of the life cycle, you run a deployed solution in a production environment. The operations phase of the life cycle involves the following tasks:
Monitoring. Includes regular monitoring of system performance and system functions.
Maintenance. Includes everyday administrative functions such as adding new end users to a system, changing passwords, adding new administrative users, changing access privileges, performing regular backups, and so forth.
Performance tuning. Includes the use of regular monitoring information to find bottlenecks in system operations and attempting to eliminate those bottlenecks by changing configuration properties, adding capacity, and so forth.
System enhancements and upgrades. Includes adding new Java ES components to a system to add new functionality or to replace non-Java ES components. These changes might require a redesign of the system, beginning with the initial phases of the solution life cycle. Upgrade tasks are more limited, usually amounting to upgrades of Java ES components.
This section explains key technical terms used in this chapter, with an emphasis on clarifying how these terms are used in the Java ES context.
A stage of the Java ES solution life cycle in which a deployment scenario is translated into a deployment design, implemented, prototyped, and rolled out in a production environment. The end product of this process is also referred to as a deployment (or deployed solution).
A logical architecture for a Java ES solution and the quality of service requirements the solution must satisfy to meet business needs. The quality of service requirements include requirements regarding performance, availability, security, serviceability, and scalability or latent capacity. A deployment scenario is the starting point for deployment design.
A task in the Java ES solution deployment process by which the custom components of a deployment architecture are programmed and tested.
A stage of the Java ES solution life cycle process in which business needs are translated into a deployment scenario: a logical architecture and a set of quality of service requirements that a solution must meet.
A deployment architecture that has been designed, implemented, and tested for performance. Reference deployment architectures are used as starting points for designing deployment architectures for custom solutions.
A specific end-user task or set of tasks performed by a distributed enterprise application and used as a basis for designing, testing, and measuring the performance of the application.