What's New in OracleAS Web Cache?

This section describes the new features of OracleAS Web Cache and provides pointers to additional information. New features information from previous releases is also retained to help those users migrating to the current release.

The following sections describe the new features in OracleAS Web Cache:

• New Features in 10g Release 2 (10.1.2)

• New Features in 10g (9.0.4)

• New Features in Release 2 (9.0.2 and 9.0.3)

New Features in 10g Release 2 (10.1.2)

The new features for OracleAS Web Cache in 10g Release 2 (10.1.2) include:

• Oracle Enterprise Manager 10g Application Server Control Support

  In previous releases, you had to use OracleAS Web Cache Manager to configure OracleAS Web Cache. In this release, you have two choices:

  • You can use Oracle Enterprise Manager 10g Application Server Control Console to configure OracleAS Web Cache along with other Oracle Application Server components.

  • You can continue to use standalone tool OracleAS Web Cache Manager.

  For standalone OracleAS Web Cache installations or installations in which OracleAS Web Cache was not installed as part of Oracle Application Server, OracleAS Web Cache Manager is the only tool provided.

  
  

  See Also: "Overview of Tools for Managing OracleAS Web Cache within Oracle Application Server" "Overview of Tools for Standalone Configurations" Oracle Application Server Administrator's Guide

  
  

• URL Path Prefix in Site Definitions

  When configuring a site definition, you can specify a URL path prefix for those sites that share the same host name. For example, by specifying /employee and /customer as prefixes, you can treat http://www.company.com/employee and http://www.company.com/customer as two distinct sites.

  
  

  See Also: "Site Definitions and Site-to-Server Mappings" "Create Site Definitions"

  
  

• Caching Rule Enhancements

  • Simplified Configuration for Excluding the Value of Embedded URL Or POST Body Parameters

    In previous releases, to ignore the value of embedded URL or POST body parameters, you had to configure a session definition for the parameter, and then configure a session caching policy. In this release, you only need to configure the name of the parameter to ignore.

    It is still possible to exclude parameters by configuring a session definition with an accompanying session caching policy. If you have a configuration that specifies the same parameter for both exclusion parameter and a session definition with an accompanying session caching policy, the session method takes precedence. To avoid conflicts, Oracle recommends migrating to the new configuration methods to exclude parameters.

  • Enabling and Disabling Caching Rules

    You can select to enable or disable caching rules. This feature is intended to provide convenience, so that you do need to create, remove, and then re-create ruled during staging and performance diagnosis.

    
    

    See Also: "Excluding the Value of Embedded URL or POST Body Parameters" for further information about excluding parameters "Configuring Caching Rules and Rule Association" for further information about enabling and disabling caching rules

    
    

• Improved Diagnostics

  • Tracking Oracle-ECID Information in the Response

    In 10g (9.0.4), OracleAS Web Cache provided the ability to log the request ID and sequence number from the Oracle-ECID request header in the event and access logs. The Oracle-ECID request header is used to track requests as they move through the Oracle Application Server architecture. OracleAS Web Cache expands support in 10g Release 2 (10.1.2) to include Oracle-ECID information whenever you configure to display diagnostic information in the Server response-header field or the HTML response body

  • Additional Access Logging Formats for Tracking Oracle-ECID Information

    In 10g (9.0.4), OracleAS Web Cache provided the End-User Performance Monitoring Format that included the x-ecid field for tracking the Oracle-ECID information. In 10g Release 2 (10.1.2), Oracle-ECID information tracking is being expanded to include two new logging formats, Enhanced CLF (ECLF) and Enhanced Combined Log Format.

  • Improved Popular Cache Requests Reporting

    The non-cacheable misses reported in the Popular Requests report have been expanded to include methods other than GET or POST request methods, HTTP status codes of non-200, requests not matching any rule with a query string, or the POST body is too large.

  
  

  See Also: "Server Response-Header Field" and "Displaying Diagnostic and Event Log Information in the HTML Body or Server Response-Header Field" for further information about configuring diagnostic output in the Server response-header field or the HTTP response message that includes Oracle-ECID information "Format of the Access Log Files" for further information about the new access log formats "Listing Popular Requests and Cache Contents"

  
  

New Features in 10g (9.0.4)

The new features for OracleAS Web Cache in 10g (9.0.4) include:

• New Invalidation Mechanisms

  • Support for Search Keys

    You can base invalidation on search keys used in the Surrogate-Key response-header field of objects in the cache.

    In previous releases, the URL-based cache key was the only identifier for a cached object. Invalidation requests needed to specify either exact URLs or a set of URLs and headers matching a regular expression in order to invalidate cached objects. Because it can be difficult for applications to map URLs to the underlying data used to generate those URLs, OracleAS Web Cache invalidation was extended in 10g (9.0.4) to support search keys. Cached objects can now be associated with multiple application-specified search keys, with the URL-based key being the primary key.

  • Support for Inline Invalidation with the <esi:invalidate> Tag

    This release introduces an inline invalidation mechanism as an additional means of managing content freshness. This inline invalidation model supplements the out-of-band invalidation model pioneered by Oracle in the very first release of OracleAS Web Cache. Inline invalidation is implemented as part of Edge Side Includes (ESI). The ability to send invalidation message inline reduces the connection overhead associated with sending out-of-band invalidations and is a useful tool for ESI developers.

    
    

    See Also: Chapter 13, "Sending Invalidation Requests"

    
    

• Usability and Manageability

  • Improved Access Logging, Event Logging, and Diagnostics

    Rollover policies for access and event logs are more flexible than in previous releases, and on-demand rollover has been added. Access log formats are now easier and more flexible to define. Administrators can also configure different access logs and logging formats for different virtual hosts serviced by the cache. New access log fields have been introduced that provide low-level request-timing diagnostics. With 10g (9.0.4), OracleAS Web Cache provides event log support for four levels of verbosity instead of two, and many of the error messages have been improved (especially for ESI errors), both of which accelerate problem diagnosis and resolution. Finally, remote diagnostic tools have been enhanced to provide more information about response failures.

    
    

    See Also: Chapter 15, "Using Diagnostics Tools"

    
    

  • Reporting on Popular Cache Misses

    Administrators can now use the browser-based OracleAS Web Cache Manager utility to get information about the most popular cache miss requests. This supplements reporting functionality in prior releases on the most popular objects in cache.

    
    

    See Also: "Listing Popular Requests and Cache Contents"

    
    

  • Integration with Oracle Process Manager and Notification (OPMN) Server

    In addition to managing Oracle HTTP Server and OC4J processes, OPMN now manages the admin server process and cache server process for OracleAS Web Cache, including the start, stop and auto-restart operations. For standalone OracleAS Web Cache deployments, administrators continue to use the webcachectl utility.

    
    

    See Also: "Managing Processes with Oracle Process Manager and Notification (OPMN)"

    
    

• Caching

  • More Flexible Multiple-Version Caching Rules for Browser Types

    In 10g (9.0.4), you can better control the granularity of multiple-version caching rules based on User-Agent request headers (browser types). You can now configure a single cache entry for each browser type (Internet Explorer, Netscape, or Mozilla), as opposed to multiple entries for each browser variant (browser version or operating system).

    
    

    See Also: "Recognizing Similar Browser Types for Multiple-Version Objects Containing HTTP Request Headers"

    
    

  • Expanded Expression Type Support

    In addition to using regular expressions, you can now apply caching rules to objects based on file extension or path prefix.

    
    

    See Also: "Selectors"

    
    

  • Maximum Size of Cached Objects

    To conserve resources, you can now configure the maximum size of objects to be cached.

    
    

    See Also: "Cached Object Size Limit"

    
    

• Security

  • Support for Client-Side SSL Certificates

    OracleAS Web Cache now supports applications that require client-side SSL certificates for PKI-based authentication. For HTTPS protocol requests that require client-side certificates, the client browser sends its certificate to Web Cache during the SSL handshake. The cache forwards the request to Oracle HTTP Server along with the client's certificate information inserted in special HTTP request headers. Oracle HTTP Server recognizes the headers and is able to pass user credentials to Oracle Application Server Single Sign-On for authentication purposes.

    
    

    See Also: "Certificate"

    
    

  • Support for nCipher SSL Acceleration Hardware

    In addition to offboard SSL acceleration solutions, Oracle Application Server now supports nCipher's BHAPI-compliant hardware for deployment on servers running OracleAS Web Cache and Oracle HTTP Server.

    
    

    See Also: "SSL Acceleration"

    
    

• Session Binding Across a Cluster

  OracleAS Web Cache provides a mechanism to ensure that all cache cluster members can determine which origin server established the session, although the request was routed originally through only one cache cluster member. As a result, subsequent requests are bound to the origin server that established the session.

  
  

  See Also: "Session Binding(Stateful Load Balancing)"

  
  

• End-User Performance Monitoring

  Using OracleAS Web Cache Manager, you can monitor the response time of your applications by viewing information about how quickly the responses are delivered to the end users.

  
  

  See Also: "Configuring End-User Performance Monitoring"

  
  

• Compression Enhancements

  • Self-Describing Compression Policies

    The Surrogate-Control response header now supports a compress control directive for enabling compression. This feature adds flexibility by enabling developers to express compression policies in the content itself, as opposed to relying on administrators to configure compression policies using the OracleAS Web Cache Manager.

  • More Compressible Content

    OracleAS Web Cache now compresses objects containing session-encoded URLs, ESI tags, or <!--WEBCACHETAG--> and <!-- WEBCACHEEND--> tags.

    
    

    See Also: "Surrogate-Control Response-Header Field"

    
    

• Improved ESI Exception Handling

  This release of ESI provides the following enhancements:

  • alt attribute of the <esi:include> tag for specifying an alternate URL if the src fragment is not found

  • Expanded try |attempt |except support for specific errors

    
    

    See Also: Chapter 16, "Edge Side Includes (ESI) Language Tags"

    
    

• Configuration Improvements

  • Configuration Improvements to OracleAS Web Cache Manager

    To help ease configuration, OracleAS Web Cache Manager supports a new navigation structure that resembles the order in which you perform configuration tasks. In addition, pages have been enhanced with purpose descriptions.

  • Dynamic Configuration

    A number of the configuration parameters in the browser-based OracleAS Web Cache Manager administration utility can now be changed on the fly, without requiring a restart of the cache.

    
    

    See Also: "Applying Static and Dynamic Configuration Changes"

    
    

  • Site Discovery

    OracleAS Web Cache Manager now provides support for discovering site and alias information from Oracle HTTP Server.

    
    

    See Also: "Create Site Definitions"

    
    

  • Default Sites

    During installation, OracleAS Web Cache defines a default site, using the host name and listening port of the computer on which the Oracle Application Server was installed.

    
    

    See Also: Default Site Settings

    
    

New Features in Release 2 (9.0.2 and 9.0.3)

The new features for OracleAS Web Cache in Release 2 (9.0.2 and 9.0.3) include:

• Automatically Restarting a Cache Server

  The auto-restart checks that the cache server process is running and automatically restarts it if it is not running.

  
  

  See Also: "Task 3: Configure Auto-Restart Settings"

  
  

• Cache Hierarchy

  You can deploy OracleAS Web Cache in a cache hierarchy so that an OracleAS Web Cache server caches content from another OracleAS Web Cache.

  
  

  See Also: "Cache Hierarchies"

  
  

• Cache Clustering

  You can configure multiple instances of OracleAS Web Cache to run as members of a cache cluster. Cache clusters provide failure detection and failover of caches, increasing the availability of your Web site.

  
  

  See Also: Chapter 3, "Cache Clustering"

  
  

• ESI Enhancements

  This release of ESI provides support for the following:

  • Embedded HTML content with the <esi:inline> tag

  • Custom environment variables with the <esi:environment> tag

  • Expanded <esi:include> tag support that provides attributes for specifying expiration, fragment time out, and the HTTP request method. In addition, new elements enable you to specify the HTTP request body of a fragment and the HTTP request header field and value for OracleAS Web Cache to use.

    
    

    See Also: Chapter 16, "Edge Side Includes (ESI) Language Tags"

    
    

• HTTPS Support Between OracleAS Web Cache and Application Web Servers

  In addition to HTTPS protocol support between browsers and OracleAS Web Cache, you can configure OracleAS Web Cache for HTTPS support between OracleAS Web Cache and at least one origin server.

  
  

  See Also: "Secure Sockets Layer (SSL)"

  
  

• Invalidation Propagation

  Invalidation messages are propagated in a cache hierarchy whereby one OracleAS Web Cache server acts as an origin server for another OracleAS Web Cache server. They are also propagated in a cache cluster with multiple OracleAS Web Cache servers.

  
  

  See Also: "Invalidation in Hierarchies" "Invalidation in Cache Clusters"

  
  

• Invalidation Preview

  You can preview the list of objects to be invalidated.

  
  

  See Also: "Invalidation Preview Request Syntax" "Oracle Enterprise Manager 10g Application Server Control Console or OracleAS Web Cache Manager to Send Invalidation Requests"

  
  

• Listing the Contents of a Cache

  You can generate a list of the URLs of the most popular objects stored in the cache and a list of the URLs of all of the objects currently in the cache.

  
  

  See Also: "Listing Popular Requests and Cache Contents"

  
  

• Oracle Enterprise Manager 10g Grid Control Support

  You can use Oracle Enterprise Manager 10g Grid Control for monitoring OracleAS Web Cache. Oracle Enterprise Manager provides a Web-based tool that enables you to view OracleAS Web Cache status and performance metrics.

  
  

  See Also: "Gathering Historical Metrics Data for OracleAS Web Cache with Oracle Enterprise Manager 10g Grid Control" Oracle Application Server Administrator's Guide

  
  

• Proxy Server Support

  In addition to application Web servers for internal sites, you can configure OracleAS Web Cache to send cache misses to proxy servers for external sites protected by a firewall.

  
  

  See Also: "Task 9: Configure Origin Server, Load Balancing, and Failover Settings"

  
  

• Site Support

  You can configure OracleAS Web Cache to cache and assemble dynamic content for one or more Web sites.

  
  

  See Also: "Virtual Hosting"

  
  

• webcachectl Commands

  The webcachectl utility provides commands for finer-grain control of the auto-restart process, cache server process, and admin server process.

  
  

  Note: If you are running OracleAS Web Cache in an environment where you have installed OracleAS Web Cache as part of an Oracle Application Server installation, you must use Oracle Process Manager and Notification (OPMN) Server to administer the OracleAS Web Cache processes. If you invoke the webcachectl utility in this situation, OracleAS Web Cache returns an error. See "Managing Processes with Oracle Process Manager and Notification (OPMN)" for information about OPMN.

  
  
  
  

  See Also: "webcachectl Utility Overview"