Tracking Your Licenses with the Key Management Service (part 1) - Installing and Initializing KMS

12/23/2011 11:29:55 AM

The Key Management Service is a service that is installed on top of the Windows Server or Client. KMS is responsible for activating clients.

1. Learning the KMS Process

Each client that attempts to activate with a KMS host is given a client machine identification (CMID) designation. The CMID is stored on both the KMS host and the KMS client, and each CMID counts for the activation threshold. Activated clients attempt to contact the KMS host every seven days by default; if this attempt fails, the client will retry every 2 hours by default. If an activated client cannot contact the KMS host within 180 days, it will deactivate and go into reduced functionality mode.

The KMS host caches twice the amount of CMIDs that are required by the KMS clients in order to prevent the CMID count from dropping below the activation threshold unexpectedly. The KMS host will decrement its activation counter by 1 when a client doesn't contact the KMS host within 30 days.

Mind the Activation Threshold

Suppose you have activated six server OSes and 20 client OSes, which leads to an activation count of 26.

Now, if four of the clients OSes don't contact the KMS host within 30 days of their last contact, the activation count will drop below 25 (which is the threshold for client activation).

As long as activation count stays below 25, this will result in a potential situation where all registered and activated client OSes will revert to not activated after 180 days. Also, no more new clients will be activated until the threshold is above 25.

The server OSes will remain activated though, because the servers are still above their activation threshold.

Systems that use KMS as their activation method find the KMS host using Domain Name System (DNS) and its Service (SRV) Resource Records (RR) functionality.

For scalability, you have the option to install multiple KMS hosts in your environment. By using DNS priority and weight parameters, you can control how clients connect to the KMS hosts; this technique works for Windows 7 and Windows Server 2008 R2 clients only, though. Windows Vista and Windows Server 2008 clients just pick a KMS host returned from the DNS query. KMS hosts do not coordinate with each other; they are stand-alone systems. Therefore, it is important that you design your KMS infrastructure with caution.

2. Choosing Your KMS Host

Before you can install your KMS host, you must first decide on which platform you are going to install your KMS. Choosing the KMS host platform depends on the type of KMS product key group you have available. When choosing the KMS host system, you must consider the operating system editions that will be activated with KMS. A KMS that is hosted on Windows 7 can only activate client operating systems, but a KMS that is hosted on Windows Server 2008 R2 Enterprise can activate both client and server computers. You must have a corresponding KMS key to activate Windows Server 2008 R2 Enterprise in the first place.

Table 1 provides an overview of the KMS host OS that should be used depending on the type of clients you want to activate.

Table 1. KMS host OS by Windows Edition
Windows Product Editions Activated by KMS	KMS Should Be Installed On
Windows 7 Professional Windows 7 Enterprise Windows Vista Business Windows Vista Enterprise	Windows Vista Windows 7 KMS for Windows Server 2003 v1.2
Products above and Windows Web Server 2008 R2 Windows Web Server 2008 Windows HPC Server 2008 R2 Windows HPC Server 2008	KMS for Windows Server 2003 v1.2 Windows Web Server 2008 Windows Web Server 2008 R2 Windows HPC Server 2008 Windows HPC Server 2008 R2
Products above and Windows Server 2008 R2 Standard Windows Server 2008 R2 Enterprise Windows Server 2008 Standard Windows Server 2008 Enterprise	Windows Server 2008 R2 Standard Windows Server 2008 R2 Enterprise Windows Server 2008 Standard Windows Server 2008 Enterprise
Products above and Windows Server 2008 R2 Datacenter Windows Server 2008 Datacenter Windows Server 2008 for itanium-based systems	Windows Server 2008 R2 Datacenter Windows Server 2008 Datacenter Windows Server 2008 for itanium-based systems

Activating Windows 7 Clients Only

When you only want to activate Windows 7 clients using KMS, keep in mind that you cannot use Windows Server 2008 or Windows Server 2008 R2 as your KMS host.

3. Selecting the KMS Host Manually

When DNS is not available for KMS host assignment, you can assign a KMS host to KMS clients by using KMS host caching. When you assign a KMS host manually, you disable auto-discovery of KMS. A KMS host is manually assigned to a KMS client by running this command:

slmgr.vbs /skms <value>:<port>

where value is the KMS host's fully qualified domain name (FQDN), the KMS host's IPv4 address, or the KMS host's NetBIOS name. The port is the TCP port used by the KMS host.

4. Installing and Initializing KMS

Depending on which version of the OS you want to install the KMS functionality, you may have to download software from the Internet. The latest KMS version, 1.2, is already included with Windows 7 and Windows Server 2008 R2. For Windows Vista, Windows Server 2003, and Windows Server 2008, you should check for an update available that updates the KMS functionality to at least version 1.2.

To enable the KMS functionality, you should first install a KMS key on the KMS host using the Windows Software Licensing Management tool. In order to do this you should supply the VLK with the highest authority that you have available, so you know for sure that the KMS can service all the OS types it needs to activate.

Use an elevated command prompt to install the KMS key:
```
slmgr.vbs /ipk <Kms Key>
```
This will install the Software Protection Service on your KMS host.
After the KMS key is installed, activate the host over the Internet or by phone. To activate online, use:
```
slmgr.vbs /ato
```
To display the Installation ID to activate over the phone, use:
```
slmgr.vbs /dti
```
To determine the number you should call to activate your KMS, enter the following command:
```
slui.exe 4
```
The output of this command will provide you with a window which asks you in which country you reside and will provide you with the various options to activate using a phone.
After the host is activated, restart the Software Protection Service. Your KMS host is now ready to activate clients.

When you're installing a KMS host key on Windows 7 or Windows Server 2008 R2 using the UI, a warning message will appear. The warning is designed to prevent you from accidentally installing KMS keys on computers that you do not intend to be KMS. You can verify that the KMS host is working correctly by checking the KMS count and determining if it is increasing as you add more KMS clients.

In a Windows command prompt window on the KMS host, enter the following:

slmgr.vbs /dli

This command will display the current KMS count (Figure 1).

Figure 1. Detailed license information

If you want even more information, you can use the /dlv option, which will give you verbose output. You can also check the Key Management Service event log for event ID 12290. This event displays the name of the computer and the timestamp of the activation request.