Your network contains an Active Directory domain named adatum.com. The domain contains three
domain controllers. The domain controllers are configured as shown in the following table.

DC3 loses network connectivity due to a hardware failure.
You plan to remove DC3 from the domain.
You log on to DC3.
You need to identify which service location (SRV) records are registered by DC3.
What should you do?

A.
Open the %windir%\system32\dns\backup\adatum.com.dns file.

B.
Open the %windir%\system32\config\netlogon.dns file.

C.
Run ipconfig /displaydns.

D.
Run dcdiag /test:dns.

Explanation:
The netlogon.dns file contains all registrations. http://support.microsoft.com/kb/816587/en-us
How to verify that SRV DNS records have been created for a domain controller The SRV record is a
Domain
Name System (DNS) resource record that is used to identify computers that host specific services.
SRV resource records are used to locate domain controllers for Active Directory. To verify SRV
locator resource records for a domain controller, use one of the following methods. DNS Manager
After you install Active
Directory on a server running the Microsoft DNS service, you can use the DNS Management Console
to verify that the appropriate zones and resource records are created for each DNS zone. Active
Directory creates its SRV records in the following folders, where Domain_Name is the name of your
domain:
Forward Lookup Zones/Domain_Name/_msdcs/dc/_sites/Default-First-Site-Name/_tcp
Forward Lookup Zones/Domain_Name/_msdcs/dc/_tcp
In these locations, an SRV record should appear for the following services:
_kerberos _ldap Netlogon.dns
If you are using non-Microsoft DNS servers to support Active Directory, you can verify SRV locator
resource records by viewing Netlogon.dns. Netlogon.dns is located in the
%systemroot%\System32\Config folder. You can use a text editor, such as Microsoft Notepad, to
view this file. The first record in the file is the domain controller’s Lightweight Directory Access
Protocol (LDAP) SRV record.
This record should appear similar to the following:
_ldap._tcp.Domain_Name
Nslookup
Nslookup is a command-line tool that displays information you can use to diagnose Domain Name
System (DNS) infrastructure.
To use Nslookup to verify the SRV records, follow these steps:
On your DNS, click Start, and then click Run.
In the Open box, type cmd.
Type nslookup, and then press ENTER.
Type set type=all, and then press ENTER.
Type _ldap._tcp.dc._msdcs.Domain_Name, where Domain_Name is the name of your domain, and
then press ENTER.
Nslookup returns one or more SRV service location records