Lesson 2

Designing a DNS Namespace

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The advantages of this solution are that it makes it impossible to create duplicate

FQDNs, and it lets you delegate authority across the internal and external domains,

which simplifies the DNS administration process. In addition, you have to register and

pay for only one Internet domain name.

Exam Tip

The question of how to create DNS domains for internal and external use is vital

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to the planning of a name resolution strategy. It is also important to understand the ramifica-

tions of using the same domain for internal and external use, of using two second-level

domains, and of creating a third-level domain.

Creating an Internal Root

When you use the Windows Server 2003 DNS server with the namespace configura-

tions described thus far, your network’s namespace is technically part of the Internet

DNS namespace, even if your private network computers are not accessible from the

Internet. This is because all your DNS servers use the root of the Internet DNS as the

ultimate source for information about any part of the namespace. When a client sends

a name resolution request to one of your DNS servers, and the server has no informa-

tion about the name, it begins the referral process by sending an iterative query to one

of the root name servers on the Internet.

If you have a large enterprise network with an extensive namespace, you can create your

own internal root. You do this by creating a private root zone on one of your Windows

Server 2003 DNS servers. This causes the DNS servers on your network to send their iter-

ative queries to your internal root name server rather than to the Internet root name

server. Keeping DNS traffic inside the enterprise speeds up the name resolution process.

Planning

Creating an internal root is recommended when the majority of your clients do

not need frequent access to resources outside your private namespace. If your clients access

the Internet through a proxy server, you can configure the proxy to perform name resolutions

by accessing the Internet DNS namespace instead of the private one. If your clients require

access to the Internet, but do not go through a proxy server, you should not create an internal

root.

Creating Host Names

After you have created the domain structure for your DNS namespace, it is time to pop-

ulate these domains with hosts. You should create hosts the same way you create

domains, by devising a naming rule and then sticking to it. In many cases, host-naming

rules are based on users, geographical locations, or the function of the computer.

For workstations, a common practice is to create host names from some variation on

the user’s name, such as a first initial followed by the user’s surname. For example, the