This article describes how to install and use IBM WebSphere Application Server (WAS) on Unix systems (chiefly Sun Solaris but most of the information is generally applicable). It's for Unix system administrators who must support WebSphere in an enterprise or production context.

It assumes that you're generally familiar with Unix system administration, TCP/IP networking, and the operation of any additional components you may require, such as Web servers and database management systems.

The goal is get you from A to B along the quickest, simplest route, where 'A' is the Unix system and a WebSphere installation CD and 'B' is an installed WebSphere application server with a working Web application. It deliberately avoids explaining J2EE technology, discussing the many implementation scenarios and other related subjects unless such information is explicitly required to complete a task.

Large-scale WebSphere deployments (i.e., the Network Deployment product) aren't described in detail either, although there's an overview of relevant issues towards the end.

We're talking specifically about WebSphere Application Server V5.1. Some of the information will also be valid for V5.0 and V6.0. Previous major releases of WebSphere differ markedly from the V5.1 release and are quickly becoming obsolete.

Note that the configurations chosen here aren't the only options and may not be correct or optimal for your situation. However, they have been proven to work and have been tested in production environments.

This piece was written in response to the lack of a direct, unambiguous guide to installing WebSphere on Unix. However, while it's designed to get you up and running quickly, it can't cover every aspect. You should expect to consult other sources where necessary.

The WebSphere Application Server Information Center is the complete, definitive guide to the product. It is supplied by IBM in HTML and PDF formats either online (see section 13) or as part of the product media set.

IBM's International Technical Support Organization (ITSO) also publishes a number of "Redbooks" that cover specific aspects of implementation. Of these, the most useful for WebSphere administrators is "IBM WebSphere Application Server V5.1 System Management and Configuration." It includes a platform-specific chapter for AIX installation; this information is also relevant to other Unix-based systems. (There is a related Redbook dealing specifically with Linux, "Installing WebSphere Application Server Version 5.1 on Red Hat Enterprise Linux Advanced Server Version 3.0.") The Redbooks can be downloaded from IBM's web site.

Of these two main sources, the Redbook is easier to follow and more immediately helpful than the Infocenter, which makes heavy use of hyperlinking that makes following a logical sequence harder. The Infocenter is, however, more detailed and comprehensive, fully searchable and useful as a reference.

IBM Press now publishes several books about WebSphere that cover administration and deployment topics more approachably than the official documentation. These are listed in the bibliography.

Getting Started
You will need at least one Unix server with an installed operating system listed by IBM in the "Prerequisites for WebSphere."

Ensure that your platform is up-to-date with all recently recommended patches and fixes before beginning. The server must be connected to a suitable TCP/IP-based network. If your WebSphere system will be part of a larger site that includes Web servers and database servers, these other systems should be installed ready for use in advance. The examples we use are from a Sun Enterprise 280R server running Solaris 8.

You will need the IBM-supplied CD-ROM (or download) labelled "WebSphere Application Server and IBM HTTP Server" for your platform. It's up to you to make sure you have the appropriate licensing and support for WebSphere. WebSphere Application Server doesn't require a license key or registration.

Download Fix Pack 1 (FP1) for WebSphere Application Server V5.1 Base from IBM's WebSphere support site. This will update the installed product to release V5.1.1.

If a later fix pack is available, download it instead. You're unlikely to need any of the cumulative or individual fixes initially, unless your development team has a specific requirement.

You'll also need a build of the application(s) you'll be running under WebSphere. WebSphere applications are normally deployed via Enterprise Application Repository (EAR) files, which are archives containing all the required files. EAR files are built and supplied by application developers. Along with the application, they should supply a list of additional requirements such as:

• Databases, including schemas and initial contents;
• Messaging services and queues;
• Key URIs, such as home pages, entry points, and administration pages;
• Minimum CPU, memory, and disk requirements;
• Any additional required setup (e.g., logging configurations, static content files, supporting utilities, and URI aliases).

Other Requirements
The WebSphere graphical installer requires X Windows. You must be able to view X11-based programs running on the host(s) on which you will be installing WAS. Either a local graphics monitor or a remote X11 server/emulator such as Cygwin/X will suffice.

A supported Web browser (generally Internet Explorer or a Mozilla variant) is required to administer WebSphere.

It's possible to install supporting products on the same system as WAS and reduce the hardware requirements in test and development environments. However, it's usually undesirable on production sites for performance, scalability. and security reasons.

Platform Resources
Ensure that each WebSphere server meets the minimum CPU, memory and disk space requirements given by IBM for running WebSphere V5.1. If possible, dedicate a separate large disk partition to the application log data.

Web Servers
Most J2EE applications are web-based, so you're likely to need a Web server or Web-serving infrastructure (such as a load balancer farm). While you can access applications on WebSphere directly using HTTP or HTTPS, this approach isn't recommended for production use since WebSphere contains no facilities for request logging or access control, nor will it perform as well as a dedicated Web server.

Read IBM's list of supported Web servers for WebSphere before selecting a suitable product. The Web server communicates with WAS using a component called the HTTP Plugin supplied with WebSphere. The plugin is available in a number of forms to support different Web servers. It can support:

• EAPI-compatible products (based on Apache, including IBM HTTP Server)
• NSAPI-compatible products (SunONE and others)
• ISAPI-compatible products on Windows platforms (e.g., Microsoft IIS).
• Lotus Domino Web server.