Settings specific to a server are stored in the local WMI repository that is created when installing a server role. These settings are accessible from the Admin Tools MMC by right-clicking a server in the tree view pane and selecting Properties, as shown in Figure 18-17.

Figure 18-17. Configuring server settings

Generally speaking, for servers that belong to the pool, most settings are configured at the pool level. That way, an administrator can configure settings only once and they will be picked up by all servers in the pool. The only settings configured at the server scope are settings that differ from server to server. For example, setting up Internet Protocol (IP) addresses, ports, and certificates fall into this category.

For servers that don’t belong to a pool (for example, Edge Servers, Mediation Servers, and Communicator Web Access Servers), all classes are scoped at the server level. Note that some pool-level classes are also accessible on certain server roles. For example, the MSFT_SIPProxySetting class is available as both a pool-level class on the front-end server and as a machine-level class on Edge Servers. To access such classes on the Edge Server, WMI must be queried with a "NULL" specified for the BackEnd property. For example, when querying for the MSFT_ SIPProxySetting class on an Edge Server, the following query must be used:

select * from MSFT_SIPProxySetting where BackEnd="NULL"

The following sections present a selective subset of machine-level WMI classes. The complete list can be found at the Microsoft Developer Network (MSDN) website: http://msdn.microsoft.com.