Your network contains an Active Directory domain named contoso.com.
You create a GlobalNames zone. You add an alias (CNAME) resource record named
Server1 to the zone. The target host of the record is server2.contoso.com.
When you ping Server1, you discover that the name fails to resolve.
You successfully resolve server2.contoso.com.
You need to ensure that you can resolve names by using the GlobalNames zone.
What should you do?

A.
From the command prompt, use the netsh tool.

B.
From the command prompt, use the dnscmd tool.

C.
From DNS Manager, modify the properties of the GlobalNames zone.

D.
From DNS Manager, modify the advanced settings of the DNS server.

Explanation:
http://technet.microsoft.com/en-us/library/cc731744.aspx
Enable GlobalNames zone support
The GlobalNames zone is not available to provide name resolution until GlobalNames zone
support is explicitly enabled by using the following command on every authoritative DNS
server in the forest:
dnscmd<ServerName> /config /enableglobalnamessupport 1