Configuring your web farm for load balancing

A web farm is a group of two or more web servers working together to handle browser requests. If you are using the default installation of Crystal Enterprise on Windows, the Web Connectors that reside on each of the web servers need to be configured so they are aware of the Web Component Servers they should communicate with.

Note:    Crystal Enterprise supports web farms with and without affinity masks.

After the connectors have been configured, they can load-balance requests between the Web Component Servers. When a web server establishes a connection with a Web Component Server, it uses a round robin algorithm to identify the next available Web Component Server. The only exceptions to this occur when a web server uses a CGI web connector, or if a session state was created on a previous request to the Web Component Server. The CGI web connector uses a random algorithm instead of a round robin algorithm because the connector doesn't have knowledge of the last Web Component Server it communicated with. Requests that had a session set up previously, must return to the same Web Component Server each time to ensure that subsequent requests have access to the previously set session state.

Tip:    Consult the documentation for your Java web application server for information on load-balancing, clustering, and scalability of these servers.

To configure a web farm for Crystal Enterprise

1. When you install the Web Connector along with the Crystal Enterprise "web content" on each of your web servers, select the same installation directory on each machine.
2. When you install multiple Web Component Servers, select the same installation directory on each machine.
3. Verify that the virtual directory mappings and the application mappings are configured identically on each web server.
4. Configure each Web Connector to communicate with all of your Web Component Servers.

   For instance, if you are running two web servers and three Web Component Servers, configure the virtual path mappings similarly for both Web Connectors, so they can both communicate with all three WCS hosts.

For complete details on installing and configuring Web Connectors for your web server, and for troubleshooting steps related to path mappings, see the Crystal Enterprise Installation Guide.