Preparing the HTTP server for load balancing

Install the IBM HTTP Server and configure the Web server plug-in for passing requests to the Jazz® for Service Management application 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 Jazz for Service Management application 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 balanced methods that are 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. When 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 Web GUI environment. The server is installed between the console and the Jazz for Service Management application 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 Jazz for Service Management application server.

About this task

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

Procedure

If IBM HTTP Server Version 8.5 is not installed, install it before you proceed. It must be installed where it can be accessed from the Internet or intranet (or both).

Note: Jazz for Service Management bundles the WebSphere Application Server Version 8.5 Supplements installation media, which contains the installation packages for IBM HTTP Server and the IBM HTTP Server plug-in for IBM® WebSphere Application Server. If you do not have the DVDs, you can download the electronic images for Jazz for Service Management, including the WebSphere Application Server Version 8.5 Supplements, from IBM Passport Advantage®. See Downloading Jazz for Service Management.
Install IBM HTTP Server ensuring that you include the IBM HTTP Server Plug-in for IBM WebSphere Application Server option.
For more information, see Installing IBM HTTP Server on distributed systems with Installation Manager.
Create a CMS-type key database.
For more information, see Working with key databases.
Note: If the certificate is not added as the default certificate, an unsupported protocol type error message is displayed when attempting to access the HTTP server using the HTTPS server address on any browser. You can also use the ikeyman utility to tag the certificate as default.
Create a self-signed certificate to allow SSL connections between nodes. Create the certificate as the default certificate.
For more information about creating a self-signed certificate with the IKEYCMD command-line interface, see Creating a self-signed certificate.
For more information about creating a self-signed certificate with the ikeyman utility, see Creating a self-signed certificate

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 that was created in step 3 and save your changes.

LoadModule ibm_ssl_module modules/mod_ibm_ssl.so
Listen 443
<VirtualHost *:443>
SSLEnable
SSLProtocolDisable SSLv2
ErrorLog "C:/Program Files (x86)/IBM/HTTPServer/logs/sslerror.log"
TransferLog "C:/Program Files (x86)/IBM/HTTPServer/logs/sslaccess.log"
KeyFile "C:/Program Files (x86)/IBM/WebSphere/Plugins_1/etc/plugin-key.kdb"
SSLStashfile "C:/Program Files (x86)/IBM/WebSphere/Plugins_1/etc/plugin-key.sth"
</VirtualHost>
SSLDisable

For more information, see the first example at Securing with SSL communications.

To let the HTTP server know where to locate the plugin-cfg.XML file, which is generated in the following steps, add the following lines to the end of the HTTP_server_install_dir/conf/httpd.conf file:
```
LoadModule was_ap22_module "/opt/IBM/WebSphere/Plugins/bin/64bits/mod_was_ap22_http.so"
WebSpherePluginConfig "/opt/IBM/WebSphere/Plugins/config/plugin-cfg.xml" 
```
When the plugin-cfg.XML file is generated, ensure that it matches the specified location.
Restart the IBM HTTP Server, For more information, see Starting and stopping IBM HTTP Server.
On the IBM HTTP Server computer, to verify that SSL is enabled ensure that you can access https://localhost.
Stop and restart the Jazz for Service Management application server:
1. In the JazzSM_WAS_Profile/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 JazzSM_WAS_Profile/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 you change 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 is forwarded to one of the nodes.

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