MCSA/MCSE Self-Paced Training Kit (Exam 70-270): Installing ...

13-30 Chapter 13 Supporting TCP/IP
F13us10
■ A zone must encompass a contiguous domain namespace. For example, in Figure
13-9, you cannot create a zone that consists of only the sales.microsoft.com
and development.microsoft.com domains because these two domains are not
contiguous.
Note For more information about contiguous namespaces, see Chapter 14.
Zone1
database
file
sales
com
microsoft
Figure 13-9 A domain namespace is divided into zones.
The name-to-IP address mappings for a zone are stored in the zone database file. Each
zone is anchored to a specific domain, referred to as the zone’s root domain. The zone
database file does not necessarily contain information for all subdomains of the zone’s
root domain, only those subdomains within the zone.
In Figure 13-9, the root domain for Zone1 is microsoft.com, and its zone file contains
the name-to-IP address mappings for the microsoft and sales domains. The root
domain for Zone2 is development, and its zone file contains the name-to-IP address
mappings only for the development domain. The zone file for Zone1 does not contain
the name-to-IP address mappings for the development domain, although development
is a subdomain of the microsoft domain.
What Are Name Servers?
Zone1
development
Zone2
Zone2
database
file
A DNS name server stores the zone database file. Name servers can store data for one
zone or multiple zones. A name server is said to have authority for the domain name
space that the zone encompasses.
One name server contains the master zone database file, referred to as the primary
zone database file, for the specified zone. As a result, there must be at least one name
server for a zone. Changes to a zone, such as adding domains or hosts, are performed
on the server that contains the primary zone database file.