Introduction › Service Concepts › Propagation Types › Aggregate Propagation

Aggregate Propagation

Aggregate propagation indicates a general-purpose relationship that propagates impact from one CI to another. Typically, an association between CIs that are part of a higher-level CI uses this propagation type. CA SOI uses the highest impact condition of all aggregate child CIs when calculating the impact on a parent CI.

Usage

Use aggregate propagation in the following situations:

• When child CIs individually affect a parent CI
• When a parent CI contains multiple child CIs that could potentially impact its condition

Examples

Examples of appropriate situations to use aggregate propagation include the following:

• A CPU or Memory CI may have aggregate propagation to the Operating System on their server.
• Services or components that make up an application may have aggregate propagation to their parent Application CI.
• The components of a network (Router, Bridge, Network Interface Card, and so on) may have aggregate propagation to a high-level Network service, CI, or group.

USM Relationships

The following USM relationships map to aggregate propagation by default in CA SOI:

• Is Impacted By
• Is Composed Of
• Is Host For
• Is Location For
• Is Manager For
• Has Member
• Has Access To

You must select one of these relationships to effect the aggregate propagation behavior. For example, you could assign Is Host For to a relationship between a ComputerSystem CI and its hosted RunningSoftware and VirtualSystem CIs. Or you could assign Is Composed Of to a ComputerSystem CI and its compositional parts. When you add services and resources to a service model, the default propagation type is aggregate with a relationship of Has Member until you change it to something else.