User Guide

230 Chapter 11 Scalability and Availability Overview
The following figure illustrates these concepts:
DNS servers store information about the domain name space and are referred to as
name servers. Name servers typically have one or more zones for which they are
responsible. The name server has authority for those zones and is aware of all the
other DNS name servers that are in the same domain.
DNS record types, server aliases, and round-robin distribution
There are three DNS record types that you must define and configure for each Web
server in order for ColdFusion’s load balancing and failover technology to work
correctly. These records must be defined and configured on your local and primary
DNS servers.
• A Record
This record contains a host name to IP address mapping, where the natural
language name is the primary name representing the IP address.
• PTR Record
This record contains the IP address to host name mapping. This is the reverse
lookup of the A record, in which given the IP address, the natural language host
To ensure that your site lookups and translations occur as intended, you must
provide correct entries in your DNS records, as shown above. Also, if you want to
enable round-robin DNS functionality, your round-robin entries must be done in the
manner shown above.
com
edu gov
...
Allaire
ftp
allaire.com Domain
dev
ntserver
...
allaire.com
Zone
dev.allaire.com
Zone