IIS configuration data is stored in the metabase in a hierarchical structure that parallels the organization of the elements of your IIS installation. Configuration data is stored in keys that are associated with IIS elements, and the keys are organized in a path structure similar to the Windows registry, or a file system. Keys are identified by their path within the metabase. For example, the path /LM specifies the local machine (computer) key, and the path /LM/W3SVC/3 specifies the key for the third Web site (virtual server). Data entries can be assigned to each key, and each data entry has a unique identifier in the metabase. For example, ServerState is a property representing data that specifies the server state, and, when located at the key having the path /LM/W3SVC/1, specifies data that describes the server state of the first virtual FTP server on the local machine. For more information about identifiers, see Reserved Identifiers and User Types.
For each FTP or Web server, the root virtual directory is given the special name ROOT. For example, the path /LM/W3SVC/1/ROOT/Scripts/Script1.asp refers to the key associated with an ASP page in the virtual directory Scripts under the first virtual FTP server on the local machine.
Note that each key name cannot be longer than the METADATA_MAX_NAME_LEN constant. This applies to each node name separately, not the entire path. In the preceding examples, the names LM and W3SVC must each be less than METADATA_MAX_NAME_LEN, but their combined path (/LM/W3SVC and so on) can be longer.
To see a graphical example of the metabase's hierarchical structure see Metabase Structure.