Specifications

Chapter 6: Administering Virtual Clusters
66 Equalizer Installation and Administration Guide
Working with Virtual Clusters
A virtual cluster acts as the network-visible front-end for a group of servers. Use the Equalizer
Administration Interface to add, configure, or remove virtual clusters and the servers that belong to
them. The figure below shows a conceptual diagram of an Equalizer with three clusters.
Figure 37 An Equalizer with three defined clusters
The parameters you specify when setting up a virtual cluster determine how the Equalizer manages
connections between the Equalizer and the servers in a cluster, and how incoming requests are
routed through the Equalizer to the cluster. Before beginning to define a cluster, we recommend that
you read this chapter in its entirety so that you can:
• Select an IP address to use for the cluster and for each server in the cluster.
• Determine the protocol (HTTP, HTTPS, Layer 4 TCP, or Layer 4 UDP) that will be used to
communicate between the Equalizer and the servers in the cluster.
• Determine the load balancing policy (round robin, static weight, adaptive, fastest response,
least connections, or server agent) that the Equalizer will use to decide how to route incoming
requests to the servers in the cluster.
• Determine the responsiveness of the Equalizer to changing loads; that is, how often and to
what degree does the Equalizer adjust the dynamic weights of the servers in the cluster.
• Determine the optional settings and flags to be used (if any) on the cluster and its servers.