Coyote Point Systems Equalizer, Installation And Administration Manual

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Working with Geographic Clusters
Equalizer Installation and Administration Guide 87
For example, assume
www.coyotepoint.com
is to be balanced across a geographical
cluster containing two Envoy sites,
east.coyotepoint.com
(at 192.168.2.44) and
west.coyotepoint.com
(at 10.0.0.5). In this case, the name servers configured to handle
the
coyotepoint.com
domain must be configured to delegate authority for
www.coyotepoint.com
to both
east.coyotepoint.com
and
west.coyotepoint.com
. When queried to resolve
www.coyotepoint.com
,
coyotepoint.com
’s name servers should return name server (NS) and alias (A) records
for both Envoy sites.
Using Envoy with Firewalled Networks
Envoy sites communicate with each other using Coyote Point’s UDP-based Geographic
Query Protocol. Similarly, Envoy sites communicate with clients using the DNS protocol. If
one or more of your Envoy sites are protected by a network firewall, the firewall must be
configured to permit the Envoy packets to pass through.
To use Envoy with firewalled networks, you need to configure the firewalls so that:
■
Envoy sites communicate with each other on UDP ports 5300 and 5301. The firewall
must allow traffic on these ports to pass between Equalizer/Envoy sites.
■
Envoy sites and clients can exchange packets on UDP port 53. The firewall must allow
traffic on this port to flow freely between an Envoy server and any Internet clients so
that clients trying to resolve hostnames via the Envoy DNS server can exchange
packets with the Envoy sites.
■
Envoy sites can send ICMP echo request packets out through the firewall and receive
ICMP echo response packets from clients outside the firewall. (When a client attempts
a DNS resolution, Envoy sites send an ICMP echo request (ping) packet to the client
and the client might respond with an ICMP echo response packet.)
Working with Geographic Clusters
Adding a Geographic Cluster
To add a new geographic cluster:
1. Log into the Equalizer Administration interface with edit access.
2. Select Add GeoCluster from the Add menu in the main menu bar. The Add
GeoCluster dialog is displayed in the right frame. You can also display this dialog by
selecting Add GeoCluster from the local menu when you’re viewing Equalizer’s
global parameters.