Application Servers and Linux: The Enterprise Awaits
It's not just for big iron anymore
Traditionally, application servers have not been players in the Linux world. Designed for enterprises to shuffle data from big iron and big databases to the Web-enabled end user, application servers are creatures of UNIX servers and Java-oriented companies.
But application servers are making their way into the Linux space--serious application servers, not just wimpy Java-processing data servers. This is a recognition of two obvious factors: a) Linux is not just for that limited departmental server stuck in the corner, and b) Linux is now a major player in the enterprise, as IT departments are now willing to devote some serious bucks (in the case of leading application servers, $10,000 or so a pop) to Linux-based applications.
Of course, it helps that application servers are now deployed in a variety of settings, including some that are conducive to Linux usage. We're now seeing clusters of application servers become the preferred method of deployment, and on a cost per unit basis it's cheaper to put up a cluster of high-end PCs running Linux than a similar number of Solaris or RS/6000 servers. And application servers have become refined enough in memory usage and processing capabilities that a network of Linux-based server can provide the necessary horsepower.
Of the major application-server vendors, Oracle (with Oracle Application Server, or OAS), BEA Systems (with WebLogic Server 4.0), Bluestone Sapphire/Web and IBM (with WebSphere Application Server) offer Linux versions of their products. This is still an anomaly in the application-server world, as makers of leading products such as Netscape Application Server, Apple WebObjects, SilverStream, Vision JADE, Haht Software's HAHTsite and Sun's NetDynamics have failed to support Linux. (Allaire is currently developing a Linux version of its popular ColdFusion application server; look for a preview in the near future.)
Still, the Linux application servers available are certainly among the leaders in this space, as well as being major players in the enterprise. These aren't after-thought products that lag behind in terms of version releases and capabilities, but real products that are the equal of releases for Sun Solaris, IBM AIX, and HP-UX. And these are releases that incorporate the latest whiz-bang technology in application-server technology: support for CORBA and COM+ objects, full support for Enterprise JavaBeans (EJBs), Java Server Pages (JSPs), XML processing, connection-pool caching and more.