WebSphere Extended Deployment, Version 6.0.x
             Operating Systems: AIX, HP-UX, Linux, Solaris, Windows, z/OS


Configuring an on demand router to dynamically update the Web server plug-in configuration

Configure an on demand router (ODR) to dynamically update the Web server plug-in configuration when the Web server forwards requests to one or more ODRs. While it is not required that the Web server forward requests to the ODR, environments exist where this topology is preferable. WebSphere® Extended Deployment offers this feature so that you do not have to manually update the plugin-cfg.xml file each time an administrative action affects this file.

Before you begin

You must decide which ODR will generate a plugin-cfg.xml file. This decision depends on how many unique plugin-cfg.xml files must be generated. Each ODR can generate a plugin-cfg.xml file that causes a Web server plug-in to route to the following elements: If all Web server plug-ins route to all ODRs, choose any single ODR to generate a plugin-cfg.xml file. If, however, you want a single Web server to front each ODR, configure each ODR to generate a plugin-cfg.xml file. The ODR uses the proxy plug-in configuration policy to determine how to generate a plugin-cfg.xml file.

About this task

By default, the ODR places the generatedplugin-cfg.xml file in the WAS_HOME/profiles/profile/etc/ directory. In the administrative console, you can override the default directory by setting the ODCPluginXmlDir JVM system property for the ODR to the desired directory. To set a JVM system property on the ODR, click Servers > On Demand Routers > odr_name > Java and Process Management > Process Definition > Java Virtual Machine > Custom Properties > New.

Since the plugin-cfg.xml file is generated by the ODR, the plugin-cfg.xml file is created on the ODR computer. The ODR that is configured to generate plugin-cfg.xml files must be running for the dynamic updates to occur. So, an application must be started for a corresponding update to the plugin-cfg.xml file to occur.

Procedure

  1. In the administrative console click Servers > On Demand Routers and select the ODR for the Web server to forward requests to.
  2. Click an ODR, then On Demand Router Properties > On Demand Router Settings.
  3. From the Generate Plugin Configuration list, select the appropriate option. The right option depends on how many ODRs a single Web server fronts. For the cell scope, the ODR generates a plug-in configuration that includes all the URIs that are handled by all the ODRs in the cell. The node scope includes all the URIs configured for the node. At the server level, the ODR only generates a plug-in configuration file for the ODR that is currently configured. This selection causes the plugin-cfg.xml file to automatically generate each time a change affects the operation of the plug-in. The plugin-cfg.xml file is on the ODR computer in the first-defined WAS_HOME/profiles/profile/etc/ directory.
  4. Restart the ODR to generate the plug-in. The plug-in is generated each time the ODR changes, for example, if the application starts or stops, or if a new application is installed.
  5. If your Web server and ODR are on different machines, set the Plugin configuration change script path. You must create this script to copy the generated plugin-cfg.xml file to your remote Web server. The script runs each time the plugin-cfg.xml file is updated.
  6. Depending on the location of the plugin-cfg.xml file on the Web server, you might also need to modify your Web server configuration file to point to the correct location of the file and restart your Web server. If you are using IBM® HTTP Server, modify the httpd.conf file in the /conf directory of your IBM HTTP Server installation.

Results

The on demand router automatically updates the plugin-cfg.xml file when changes occur to the configuration.

What to do next

You can also perform this task manually from the administrative console. In the console, click Servers > Web Servers > Generate Plug-in to configure the plugin-cfg.xml file.



Subtopics
Controlling the generation of the plugin-cfg.xml file
Related concepts
Overview of request flow prioritization
Related tasks
Creating ODRs
Task topic    

Terms of Use | Feedback

Last updated: Nov 30, 2007 3:58:31 PM EST
http://publib.boulder.ibm.com/infocenter/wxdinfo/v6r0/index.jsp?topic=/com.ibm.websphere.xd.doc/info/odoe_task/todrWebserver.html