Preparing the HTTP server for load balancing

Install the IBM HTTP Server and configure the Web server plug-in for passing requests to the Tivoli Integrated Portal Server that are part of the load balancing configuration.

Before you begin

The IBM HTTP Server uses a Web server plug-in to forward HTTP requests to the Tivoli Integrated Portal Server. You can configure the HTTP server and the Web server plug-in to act as the load balancing server, that is, pass requests (HTTP or HTTPS) to one of any number of nodes. The load balancing methods supported by the plug-in are round robin and random:

With a round robin configuration, when a browser connects to the HTTP server, it is directed to one of the configured nodes. When another browser connects, it is directed to a different node.
With the random setting, each browser is connected randomly to a node. Once a connection is established between a browser and a particular node, that connection remains until the user logs out or the browser is closed.

The HTTP server is necessary for directing traffic from browsers to the applications that run in the Tivoli Integrated Portal environment. The server is installed between the portal and the Tivoli Integrated Portal Server, and is outside the firewall.

The Web server plug-in uses the plugin-cfg.xml configuration file to determine whether a request is for the application server.

About this task

Complete this procedure to configure the Web server plug-in for load balancing for each node.

Procedure

If you do not already have the IBM HTTP Server installed, install it before proceeding. It should be installed where it can be accessed from the Internet or Intranet (or both). Select the link at the end of this topic for the installation procedure.
Install IBM HTTP Server ensuring that you include the IBM HTTP Server Plug-in for IBM WebSphere Application Server option. For more information, see http://publib.boulder.ibm.com/infocenter/wasinfo/fep/topic/com.ibm.websphere.ihs.doc/info/ihs/ihs/tihs_installihs.html.
Create a new CMS-type key database. For more information see http://publib.boulder.ibm.com/infocenter/wasinfo/fep/index.jsp?topic=/com.ibm.websphere.ihs.doc/info/ihs/ihs/tihs_createkeydb.html.
Create a self-signed certificate to allow SSL connections between nodes. For more information, see http://publib.boulder.ibm.com/infocenter/wasinfo/fep/index.jsp?topic=/com.ibm.websphere.ihs.doc/info/ihs/ihs/tihs_certselfsigned.html.
To enable SSL communications for the IBM HTTP Server, in a text editor, open HTTP_server_install_dir/conf/httpd.conf. Locate the line # End of example SSL configuration and add the following lines, ensuring that the KeyFile line references the key database file created in step 3 and save your changes.
```
LoadModule ibm_ssl_module modules/mod_ibm_ssl.so
<IfModule mod_ibm_ssl.c>
  Listen 443
  <VirtualHost *:443>
    SSLEnable
  </VirtualHost>
</IfModule>
SSLDisable	  
KeyFile "C:/Program Files/IBM/HTTPServer/bin/test.kdb"
```
For more information, refer to the first example at http://publib.boulder.ibm.com/infocenter/wasinfo/fep/index.jsp?topic=/com.ibm.websphere.ihs.doc/info/ihs/ihs/tihs_setupssl.html.
Restart the IBM HTTP Server. For more information, see http://publib.boulder.ibm.com/infocenter/wasinfo/fep/topic/com.ibm.websphere.ihs.doc/info/ihs/ihs/tihs_startihs.html.
On the IBM HTTP Server computer, to verify that SSL is enabled ensure that you can access https://localhost.
Stop and restart the Tivoli Integrated Portal Server:
1. In the tip_home_dir/profiles/TIPProfile/bin directory, depending on your operating system, enter one of the following commands:
  - stopServer.bat server1
  - stopServer.sh server1
    Note: On UNIX and Linux systems, you are prompted to provide an administrator username and password.
2. In the tip_home_dir/profiles/TIPProfile/bin directory, depending on your operating system, enter one of the following commands:
  - startServer.bat server1
  - startServer.sh server1
Start the HTTP server:
1. Change to the directory where it is installed.
2. Run this command: bin/apachectl start Note you must restart the server after changing the plugin-cfg.xml file.

What to do next

Enter the URL for the HTTP Server in a browser http://HTTP_server_host/HTTP_server_port and it will be forwarded to one of the nodes.

Note: The default load balancing method is random, whereby each browser is connected randomly to a node.