About Client Site Assignment in Configuration Manager
Applies To: System Center Configuration Manager 2007, System Center Configuration Manager 2007 R2, System Center Configuration Manager 2007 R3, System Center Configuration Manager 2007 SP1, System Center Configuration Manager 2007 SP2
After a Configuration Manager 2007 client is installed, it must join a Configuration Manager 2007 primary site before it can be managed. The site that a client computer joins is referred to as its assigned site.
Configuration Manager 2007 clients cannot be assigned to secondary sites; they are always assigned to the parent primary site. However, if they reside in the boundaries of the secondary site, they can take advantage of any proxy management points and distribution points at the secondary site.
The assignment process occurs after the client is successfully installed, and determines which site manages the client computer. However, it is possible to install a client and not immediately assign it to a site, but in this scenario it is considered an unmanaged client until site assignment is successful.
You can either directly assign a client to a site, or use auto-site assignment where the client automatically finds an appropriate site based on its current network location.
After the client is assigned to a site, it remains assigned to that site even if it changes its IP address and roams to another site. Only an administrator can later manually assign the client to another site or remove the client assignment.
If the client fails to assign to a site, the client software remains installed, but will be unmanaged.
A client is considered unmanaged when it is installed but not assigned to a site, or is assigned to a site but cannot communicate with that site's default management point.
How Manual Site Assignment Works
Clients can be manually assigned to a site using the following two methods:
A client installation property which specifies the site code.
Specifying the site code in Configuration Manager in the computer's Control Panel.
If you manually assign a client computer to a Configuration Manager 2007 site code that does not exist, site assignment will fail. The client will remain installed but unmanaged until it is assigned to a valid Configuration Manager 2007 site.
How Auto-Site Assignment Works
Auto-site assignment can occur during client deployment or when you click Discover in the Configuration Manager Properties: Advanced Tab. The Configuration Manager client compares its own IP address with the site boundaries configured in the Configuration Manager 2007 hierarchy. When the client IP address falls within the boundaries of a site, the client is automatically assigned to that site.
Boundaries are configured for one or more of the following:
Active Directory site
IP v6 prefix
IP address range
If a Configuration Manager 2007 client has multiple network cards (possibly a LAN network card and a dial-up modem), and therefore has multiple IP addresses, the IP address used to an evaluate client site assignment is nondeterministic.
Configuration Manager 2007 clients that use auto-assignment attempt to find site boundaries published to Active Directory Domain Services. If this method fails (for example, the Active Directory schema is not extended for Configuration Manager 2007, or clients are not within the same forest), clients can find boundary information from a server locator point.
The server locator point can be directly assigned to the client during installation, or the client can attempt to locate it using WINS. For more information about locating a service locator point through WINS, see Configuration Manager and Service Location (Site Information and Management Points).
If the client cannot find a site configured with boundaries that match its own IP address, the client will retry every 10 minutes until it is able to assign to a site.
Configuration Manager 2007 clients cannot be automatically assigned to a site if any of the following scenarios apply, and instead they must be manually assigned:
They are currently assigned to a site.
You want to manage them as Internet-based clients.
They will locate the site's default management point using DNS publishing
Their IP address does not fall within one of the configured boundaries in the Configuration Manager hierarchy.
Completing Site Assignment by Checking Site Compatibility
After a client has found its assigned site, the client's version is checked to ensure that a Configuration Manager 2007 client is not incorrectly assigned to an SMS 2003 site. Additionally, if the client is running Windows 2000, a further check is made to ensure that it is not being assigned to a Configuration Manager 2007 site that is configured for native mode. Both of these configurations would result in an unmanaged client, so site assignment checks identify this misconfiguration.
The site compatibility check requires one of the following conditions:
The client can access site information published in Active Directory Domain Services.
The client can access a server locator point.
If the site compatibility check fails to complete successfully, site assignment will fail and the client will remain unmanaged until the site compatibility check is successful.
The exception to performing the site compatibility check is when a native mode client is configured for an Internet-based management point. In this scenario, no site compatibility check is made. If you are assigning clients to an Internet-based site and specifying an Internet-based management point, take particular care that you are assigning the client to the correct site. For more information about configuring clients for Internet-based client management, see Administrator Checklist: Configuring Client Computers for a Site that Supports Internet-Based Client Management.
Locating the Default Management Point
After a client is successfully assigned to a site, it must then locate that site's default management point so that it can download its client policy. Or, if it assigned when on the Internet, it connects to its specified Internet-based management point. When the client has downloaded client policy from its assigned site's management point, the client is then a managed client.
For more information about how clients locate their default management point and find server locator points, see Configuration Manager and Service Location (Site Information and Management Points).
For more information about managing clients on the Internet, see Deploying Configuration Manager Sites to Support Internet-Based Clients.
Locating Site Mode and Related Settings
After site assignment succeeds and the client has found its default management point, a client that uses Active Directory Domain Services for its site compatibility check will locate the site mode settings for its assigned site.
When there is a site mode mismatch between client and site (for example, a mixed mode client is assigned to a native mode site), the client will be automatically reconfigured for the correct client communication mode so that it can communicate with its assigned site. Additionally, any other site mode related settings will also be configured on the client, such as the certificate selection criteria, whether to use a certificate revocation list, and the client request port numbers. The client continues to check these settings on a periodic basis.
However, a client that uses a server locator point for its site compatibility check cannot be automatically reconfigured. This means that a mixed mode client that is assigned to a native mode site (or a native mode client assigned to a mixed mode site) will be unable to communicate with the site until the administrator reconfigures its client communication mode manually (for example, reinstalls it with the CCMSetup native mode option). Additionally, all client options relating to native mode configuration must be specified during installation by using client installation properties. For more information, see About Configuration Manager Client Installation Properties.
Site Assignment Scenarios
For example scenarios of how client site assignment works in different circumstances, see the following:
Overview of Configuration Manager Client Deployment
Choose Configuration Manager Boundaries
Decide If You Should Extend the Active Directory Schema
Understanding Configuration Manager Clients
About Client Roaming in Configuration Manager
Determine If You Need a Server Locator Point for Configuration Manager Clients
For additional information, see Configuration Manager 2007 Information and Support.
To contact the documentation team, email SMSdocs@microsoft.com.