Oracle also sells two Enterprise Edition options, a personalization engine and a wireless and mobile device publishing add-on. Each of these costs $10,000 per CPU. Both the Standard Edition and Enterprise Edition are available on Windows, Linux, Solaris and several other Unix operating systems and support all major Web servers. We tested the Windows version of the Enterprise Edition with the built-in Apache Web server. (The Windows code started shipping in June.)Oracle9i Application Server Release 2s management console has been reworked and now uses Oracles standard Enterprise Manager console to manage servers and clusters. In fact, Oracle has been working on making clustering seamless. We built a cluster of three machines and were able to deploy a single application to all of them in a single step. Enterprise Edition uses a database-based configuration repository to manage clusters, and many administrative tasks automatically apply clusterwide with the repository installed. Unfortunately, this repository does not support Oracles RAC (Real Application Clusters) or other methods of building highly available Oracle databasesa manual database switch-over is required if the repository database (which is a single point of failure) goes down. RAC support will ship by the end of the year, according to Oracle officials. Oracle9i Application Server supports HTTP session object and EJB clustering and provides in-memory replication of state information. With state replication enabled, we were able to kill any selected application server Java virtual machine in tests and still not lose state information. EJB state replication has scalability problems because all EJB objects broadcast state information to all other machines in the cluster. A way to create smaller state replication zones (which is possible with HTTP session clustering) would be more efficient. Round-robin load balancing is the only option available. Weighted round robin is planned and would allow for clusters of machines of different strengths. West Coast Technical Director Timothy Dyck is at firstname.lastname@example.org.
Development versions of the application server are free, and integration plug-ins are available for all the major Java development tools.