Specifications

Chapter 1: Overview
8 Equalizer Installation and Administration Guide
4. The client’s DNS selects one of the Equalizers in the list and queries it. If the queried site
doesn’t respond, the client tries each of the other sites.
5. Envoy returns the IP Address of the virtual cluster best able to handle the client’s request.
For more information on geographic load balancing using Envoy, see “Administering Geographic
Clusters” on page 149.
Configuring the Equalizer Network
Equalizer is a versatile traffic management solution. It works in a single or dual network mode. If
you have a second unit, you can use it as a hot-backup unit. Equalizer also works with servers
placed on a reserved, non-routable network and allows for IP address aliasing.
You can use Equalizer in a number of configurations. Before you install Equalizer, you need to
determine where it will fit into your network and how you will configure it. This section describes
some configuration choices. The following section provides a worksheet to help you plan your
configuration.
Equalizer’s Network Ports
All Equalizers have two types of network ports: external and server. The external port is always a
single port labeled External or Ext. The server ports are labeled Int on dual-port models or labeled
with numbers on switch-based models. Depending on the Equalizer switch-based model, there may
be four or more of these ports.
Figure 6 EqualizerE350si
Equalizer’s External Port
The external port is connected to the network to which the client machines and possibly the Internet
or an Intranet are connected. This external network receives the client request packets that Equalizer
distributes across the available servers. Equalizer also uses the external network to transmit
Serial Port
External Port
Server Ports