Server farms

A server farm is a group of identical servers accessed through hardware or software load balancing technology. All the servers are active, provide the same set of services, and are effectively interchangeable. A load balancer distributes incoming client requests over the servers in the group.

Server farms are best suited to server tiers such as Content Platform Engine web applications that are processing-centric rather than data-centric because all the servers in the farm are clones of each other. Processing logic for these components does not change often, making it easy to keep all the servers identical.

Figure 1. The basic server farm setup
The basic server farm setup

A load-balanced server farm provides both better availability and better scalability than a single server. When a server fails, the load balancer automatically detects the failure and redirects user requests to another server in the farm, thereby keeping the site available. Administrators can increase system performance and capacity by adding servers to the farm.

With a hardware-based load balancing solution, redundant load balancers are required to avoid a single point of failure. The software-based load balancers are typically designed to avoid a single point of failure by running the network load balancing software on each server in the farm.