NonStop Server Guide for BEA WebLogic Server 8.1

HP NonStop Server Guide for BEA WebLogic Server 8.1—529891-001
8-1
8 Using the WS Plug-in
Comparison of RLS and WS Plug-in
Architecture
Installing and Building the WS Plug-in
Configuring the WS Plug-in
WS Plug-in Configuration Tool
Migration Considerations
WS Plug-in Event Messages (5000 through 5024)
Troubleshooting
Comparison of RLS and WS Plug-in
Overview
The WS Plug-in replaces the version of the Resource Locator Service (RLS)
distributed with iTP Secure WebServer. The RLS is an optional feature of iTP Secure
WebServer. It enables multiple web servers to appear as a single server to users. See
the HP iTP Secure WebServer documentation for more information.
The WS Plug-in is distributed with the NonStop Server Toolkit. It supports stateful
dialogs between web clients (usually a browser) and J2EE application servers. It also
supports more sophisticated load balancing and configuration options. The WS Plug-in
also supports web applications that utilize session-based dialogs. Therefore, because
the WebLogic Server is a J2EE application server platform that includes a web
container (which uses session based dialogs), you must use the WS Plug-in in place of
the RLS product distributed with iTP WebServer.
Using DBACCESS Table
The iTP Secure WebServer version of the RLS uses a single SQL/MP table (called
DBACCESS) to configure the servers to which requests are forwarded. This approach
is not practical in a J2EE environment where many applications are deployed in a
cluster of application servers. Because each web application has a separate pathname
prefix, a separate entry is required for each prefix to target server combinations.
Using WS Plug-in, you can group a number of target servers (usually application
servers) together as a cluster. Therefore, you must define the cluster only once. Many
different applications (defined by their pathname prefix) can be routed to that cluster.
WS Plug-in also provides a number of new features related to load balancing and
request redirection that are especially designed for use with application servers. These
features are enabled on a per-application basis using an additional column (titled
noredirect) in the DBACCESS table. If this column contains a non-zero value, the
J2EE mode is enabled.