Configure high-speed external caching through the Web server

 

Overview

IBM HTTP Server for Windows NT and Windows 2000 operating systems contains a high-speed cache referred to as the Fast Response Cache Accelerator, or cache accelerator.

The Fast Response Cache Accelerator is available on Windows NT and Windows 2000 operating systems and AIX platforms. However, support to cache dynamic content is only available on Windows NT and Windows 2000 operating systems.

We can enable cache accelerator to cache static and dynamic content. To enable cache accelerator for caching static content, add the following directives to the http.conf configuration file, in the IBM HTTP Server conf directory:

• AfpaEnable

• AfpaCache on

• AfpaLogFile "install_root\IBMHttpServer\logs\afpalog" V-ECLF

To enable cache accelerator for caching dynamic content, such as servlets and JavaServer Pages (JSP) files, configure the WebSphere Application Server and the IBM HTTP Server for distributed platforms:

 

Procedure

1. Configure WAS to enable Fast Response Cache Accelerator. It is important to follow all the steps for every application server in the cluster.

   1. On distributed platforms, turn on servlet caching for each application server that uses the cache accelerator.

   2. Configure an external cache group on the application server:

      1. Click Servers > Application servers > servername > Container services > Dynamic cache service > External cache groups.

      2. Click New on the External cache group administrative console page to define an external cache group named afpa for each application server that uses the cache accelerator.

      3. In the External cache group field, type afpa and apply the changes.

   3. Add a member to the group with an adapter bean name of com.ibm.ws.cache.servlet.Afpa.

      1. Click Afpa > External cache group members.

      2. Click New on the External cache group members administrative console page.

      3. In the AdapterBean name field, type com.ibm.ws.cache.servlet.Afpa.

      4. In the Address field, enter an unused port number.

   4. Add a cache policy in the cachespec.xml file for the servlet or JSP file you want to cache. Add the following property to the cache policy:

      <property name="ExternalCache">afpa</property>
      

2. Enable cache accelerator on the IBM HTTP Server for distributed platforms:

   1. Add the following directives to the end of the httpd.conf file:

      • AfpaEnable

      • AfpaCache on

      • AfpaLogFile "install_root\IBMHttpServer\logs\afpalog" V-ECLF

      • LoadModule afpaplugin_module install_root/bin/afpaplugin.dll

      • AfpaPluginHost WAS_Hostname:port, where WAS_Hostname is the host name of the application server and port is the port you specified in the Address field while configuring the external cache group member

   The LoadModule directive loads the IBM HTTP Server plug-in that connects the Fast Response Cache Accelerator to the WAS fragment cache. If multiple IBM HTTP Servers are routing requests to a single application server, add the directives above to the http.conf file of each of these IBM HTTP Servers for distributed platforms. If one IBM HTTP Server is routing requests to a cluster of application servers, add the AfpaPluginHost WAS_Hostname:port directive to the http.conf file for each application server in the cluster. For example, if there are three application servers in the cluster, add the following directives to the http.conf file:

   • LoadModule afpaplugin_module install_root/bin/afpaplugin.dll

   • AfpaPluginHost WAS1_Hostname:port1

   • AfpaPluginHost WAS2_Hostname:port2

   • AfpaPluginHost WAS3_Hostname:port3

 

See also

Configuring fast response cache accelerator cache size through a distributed platforms Web server

 

Related Tasks

Communicating with Web servers

 

See Also

Cachespec.xml file

 

---