Service hierarchy overview

A service hierarchy is a logical organization of the services you provide, each higher level covering a wider or more general service area than the next lower level. The picture below shows a simple service hierarchy. The top level service is E-mail. This service is dependent on two lower level services, America and Europe, which in this case represent e-mail services on two continents. These services depend on other services, down to the lowest level services, in this case, the hard disks and CPUs of specific computers. This sample is small but a service hierarchy can include many more services and relationships. (Click the boxes and arrows below for more information about this service hierarchy example.)

Service Hierarchy Terms

The terms below are used in the help to describe the relationships between the various services in a service hierarchy.

• The terms superordinate and subordinate describe the hierarchical relationship between two services in the service hierarchy. A superordinate service depends on one or more subordinate services, and uses the statuses of its subordinates to calculate its own status. All services to which a service propagates its status are considered to be that service's superordinates. A service can be both superordinate and subordinate at the same time.
• Dependency describes the relationship between a superordinate service and a subordinate service. The superordinate depends on the services of the subordinate to function properly, and also depends on the status of the subordinate services to calculate its own status.
• A contained by link describes the relationship of a subservice which cannot exist without a superordinate service. In the example above, the service CPU 1 cannot exist if its superordinate service Computer 1 does not exist. If Computer 1 is removed from the service hierarchy, CPU 1 cannot exist in the service hierarchy.
• A used by link describes the relationship of a subservice which can exist without the superordinate service. In the example above, the service Computer 1 can exist if its superordinate service Mail Server 1 does not exist. If Mail Server 1 is removed from the service hierarchy, Computer 1 will remain in the service hierarchy.

Related Topics:
Planning your service hierarchy