Relationship status propagation concepts

The cell performs status propagation for relationships, and it relies on the status propagation model associated with each impact relationship instance.

Each status propagation model must have a unique name to identify it. You can create as many status propagation models as needed to control component status propagation. The name of a single BMC_STATUS_PROPAGATION refers to multiple BMC_PROPAGATION_MAP instances all of which have the same name (a one-to-many relationship). Each BMC_PROPAGATION_MAP instance defines how a provider component status is propagated over a relationship to the consumer component.

For example, for an INCREASING status propagation, there will be a number of propagation map instances each of which increases the status propagated by a provider component to a consumer component. So, if a provider has status MINOR, the status propagated over the relationship to the consumer will be IMPACTED. This would be a single propagation map instances; one is needed for each status.

 How status propagation works

The cell automatically propagates the status of CIs through its outbound relationships as new conditions occur, such as a status change on the component or a state change on an outbound relationship. Status propagation is based on impact relationships and status propagation models.

The role of a status propagation model is to define the status value to be propagated in all possible situations. That model can then be applied to one or more impact relationship instances, enabling the cell to handle status propagation appropriately for those objects.

When a status change on a CI triggers a status propagation, the cell takes the main status (status slot value) of the component, retrieves each outbound impact relationship with its associated state and its status propagation model, and searches the propagation map for a matching entry. The result is the propagated_status value, which is passed as an input to the impact_function of each consumer component.

When a state change on an outbound impact relationship triggers a new status propagation for that CI, the cell combines the main status of the component with the retrieved state and the status propagation model of the relationship, and searches the propagation map of the status propagation model for a matching entry. The result is the propagated_status value, which is then passed as an input to the impact_function of the consumer component.