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


Configuring ODRs

Configure an on demand router (ODR) to determine how it handles failure scenarios and how to tune certain work requests. You can configure the connections and requests to the application server, configure the requests that must be rejected, define how error responses are handled, and specify the location of the proxy logs. The configuration of the ODR in the DMZ is not supported.

Before you begin

After the ODR is created, it senses the environment and can route work to WebSphere® Extended Deployment application servers.You must first create an ODR, a proxy with advanced capabilities that WebSphere Extended Deployment uses to route work to application server nodes. See Creating ODRs for more details.

About this task

You can define the configuration of the ODR by editing its proxy configuration. Define the configuration further by clicking Servers > On Demand Routers >odr_name> On demand router properties > On demand router settings. Note that the configuration of the ODR in the DMZ is not supported.

Procedure

  1. Define and configure the connections and requests between the ODR and the application servers that issue the request.
  2. By default, caching content is enabled. The properties that follow apply only if caching is enabled.
    • Enable - Enables caching framework for the ODR server and enables static content caching, as defined by HTTP 1.1 specifications.
    • Cache instance name - The dynamic cache object cache instance, that is configured under Resources > Cache instances > Object cache instances, used to cache all static and dynamic content responses. This object cache instance must be configured to support new I/O (NIO) application program interfaces (APIs).
    • Cache SSL content - Determines whether client ODR SSL connections that are terminated by the ODR should have their responses cached.
    • Cache Aggressively - Enables caching of HTTP responses that would not normally be cached. Caching rules that are defined by HTTP 1.1 can be broken to gain caching optimization.
    • Cache Dynamic Content - Determines whether dynamic content that is generated by WebSphere Application Servers V6.02, or later, is cached. Caching dynamic content generated by content servers prior to WebSphere Application Server V6.02 is not supported
    • Cache update URI - When caching dynamic content, this is the relative URI of an installed content server application that is used to invalidate cached entries.
  3. Define exclusions. The ODR examines every incoming request. You can define certain methods for exclusion, and if the requested HTTP method matches any of the configured methods, the ODR rejects the requests with a Method Disallowed error.
  4. Logging is enabled by default. HTTP requests are logged in one of three logs: proxy, cache, and local. Local log configuration is not available in the administrative console, but is available at ${SERVER_LOG_ROOT}local.log. Specify the location of this log by setting the http.log.localFileName custom property to the file location. The content of each log is formatted using the National Center for Supercomputing Applications common log format.
  5. Define trusted security proxies. A trusted security proxy is a process that receives requests prior to the ODR and then forwards requests to the ODR. For example, a Web server with the WebSphere Application Web server plug-in might forward requests to the ODR. A trusted security proxy is allowed to pass information such as the virtual host name, or user identity to the ODR in private HTTP headers. Private headers received from an untrusted proxy are discarded by the ODR. Use an Internet Protocol or fully-qualified host name in this field.
  6. Create a proxy plug-in configuration policy on a cell level. A proxy plug-in configuration policy generates a proxy plug-in configuration file that can be used on a Web server that routes requests to the ODR. The plug-in can determine the URI that the proxy is handling on behalf of the application server and the endpoint, or boundaries of the proxy so that it can properly route requests to the proxy. Note that the configuration of the ODR in the DMZ is not supported.
    You have three options, other than none or all, for defining a scope by which to generate the plug-in.
    1. Cell: The ODR generates a plug-in configuration that includes all the URIs that are handled by all the ODRs in the cell.
    2. Node: Includes all the URIs that are configured for the node
    3. Server: Generates a plug-in configuration file for the ODR that is currently configured.
  7. Install an error page application on the ODR. From the base server installation install_root/installableApps directory, install the HttpErrorHandler.ear sample error page application by issuing the command:
    $AdminApp install <path_to_application ear> <file> [list -server <name_of_ODR_server> -node <name_of_ODR node>]
    Install this application on the ODR to minimize latency. The HttpErrorHandler.ear file also contains sample source code to use as a starting point to create your own error page application.
  8. Type the Error page generation application URI. Define your custom error page policy. For example, if you use the HttpErrorHandler.ear sample application, use the /ErrorPageApp/ErrorPage URI. Customized error pages with this definition can be used when errors occur during the processing of the request.
  9. Configure HTTP response codes to handle. In the HTTP status codes that are to be recognized as errors field, type any specific HTTP response codes for your error page application to handle and click OK. Use separate lines and comma separation for multiple codes and X as a wildcard character to denote code ranges. For example, type 4XX to denote all status codes between 400 and 499. Ensure that each error code is on a separate line. For example:
    4xx
    5xx

What to do next

After you create and configure the ODR and apply any configuration parameters, you can define the ability to route work to non-Extended Deployment nodes.



Related concepts
Overview of request flow prioritization
Related tasks
Creating or editing a node group
Configuring the on demand router for multi-cluster failover and load balancing routing
Related reference
Creating and deleting on demand routers with scripts
Administrative roles and privileges
Related information
Proxy server settings
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/todoeconfigodr.html