Health evaluation can be performed manually by a user or by automated services employed to report on the system health. Health policies are used to evaluate and report the health of an entity which is then aggregated at a parent level in the entity hierarchy. This process cascades up to the root element of the hierarchy which is the Cluster. The following diagram illustrates this process of cascading aggregations:
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Cascading aggregations
After the health of child elements are evaluated, the health sub-system evaluates the health of a parent entity based on the maximum percentage of unhealthy children configured at a specific level.