Coyote Point Systems Equalizer, Installation And Administration Manual

Page: 21 / 144

Equalizer Network Configurations
Equalizer Installation and Administration Guide 11
Equalizer can be used in a number of different configurations. Before you install Equalizer,
you need to determine where it will fit into your network and how it will be configured.
This section describes some of the different configuration choices that you have and
provides a configuration worksheet to help you plan your configuration.
Using IP Aliases
IP address aliasing enables a single physical server to respond to more than one IP
address. This technique is often used to implement several virtual web servers on one
machine.
Virtual clusters can be configured using aliased IP addresses. For example, two clusters
could be configured using four unique server addresses:
Cluster 199.146.85.5:80
Server 199.146.90.10:80
Server 199.146.90.11:80
Cluster 199.146.85.6:80
Server 199.146.90.12:80
Server 199.146.90.13:80
Although four different servers are specified, using IP address aliasing enables you to
implement this configuration with just two physical servers. For example, IP addresses
199.146.90.10
and
199.146.90.12
might be configured as aliases on one machine
and IP addresses
199.146.90.11:80
and
199.146.90.13
configured on the other.
The process of configuring IP aliases and virtual web servers is operating-system and
server-software dependent; consult your platform and server documentation for details.
Using Equalizer as a Gateway Between Networks
The most common Equalizer configuration is to have Equalizer function as the gateway
between two separate networks—the internal network where the servers reside, and the
external network to which clients and the Internet or an Intranet are attached. Figure 7 on
page 12 shows this configuration in detail.