Your company has a single Active Directory domain named contoso.com. The domain has two domain controllers and 60 member servers.

All servers run Windows Server 2008 R2.

One of the domain controllers has Key Management Service (KMS) installed and activated.

All servers use KMS auto-discovery to find the KMS server.

You need to change the port used by KMS from its default port to port 12200.

Which two actions should you perform? (Each correct answer presents part of the solution. Choose two.)

A.
Restart the slsvc service on the KMS server.

B.
Restart the DNS Server service on the KMS server.

C.
On the KMS server at the command prompt, run the slmgr.vbs �srpt 12200 command.

D.
On the client computers at the command prompt, run the slmgr.vbs �skms KMSServer: 12200 command.

Explanation:
To change the port of the KMS server:
To set the TCP communications port on a KMS host. Replace PortNumber with the TCP port number to use. The default setting is 1688.
slmgr.vbs /sprt PortNumber

Source: http://technet.microsoft.com/en-us/library/ff793407.aspx

Restart slsvc service:
A KMS host will automatically update its SRV entries if the software licensing service (slsvc.exe) detects that the computer name or TCP port has changed during service startup. It will also update them once each day, in order to ensure that they are not automatically removed (scavenged) by the DNS system.

Source: http://download.microsoft.com/download/c/3/8/c3815ed7-aee7-4435-802b-8e855d549154/VolumeActivation2.0Step-By-StepGuide.doc

Force the KMS client to update the portnumber (not needed here):
If configuring KMS clients to use auto-discovery, they automatically choose another KMS host if the original KMS host does not respond to renewal requests. If not using auto-discovery, update the KMS client computers that were assigned to the failed KMS host by running Slmgr.vbs /skms. To avoid this scenario, configure KMS clients to use auto-discovery. For more information, see the Volume Activation Deployment Guide.

Source: http://technet.microsoft.com/en-us/library/ff793439.aspx