Understanding topology synchronization

The Global Manager maintains an abstracted representation of the topology discovered by the Domain Managers and the topology from the Adapter Platform. When the Domain Manager completes a discovery, the Global Manager resynchronizes the topology from the Domain Managers.

In all cases, the Global Manager does a full topology synchronization, even when only one device is added to an underlying domain. This means that topology synchronization is most efficient when it occurs less frequently, but with larger sets of changed devices. The Global Manager resynchronizes topology after a single device discovery, a pending discovery, or a full rediscovery.

Another important aspect of topology synchronization is synchronization between the Global Manager and the Adapter Platform. The Adapter Platform is typically configured to contain some of the topology from the IP Availability Manager. With this topology, the Adapter Platform matches events to devices managed in the IP Availability Manager. So, the Adapter Platform often contains all of the IP Availability Manager topology and also some topology created based on events received as traps, or from other sources.

When the Global Manager synchronizes topology with the Adapter Platform, the topology inherited from the IP Availability Manager, as well as the topology created due to events from traps or other sources, is synchronized. This means that a Global Manager may synchronize topology twice when a change is made to a device in IP Availability Manager: once with the IP Availability Manager and then once with the Adapter Platform.

The Adapter Platform does not contain all of the topology from the IP Availability Manager. So, the synchronization it performs with the Global Manager for the topology from IP Availability Manager is less performance-intensive than the synchronization between the Global Manager and the IP Availability Manager.

Topology synchronizations in the Global Manager may be done concurrently. If there are a number of underlying domains that need to synchronize topology at the same time, the Global Manager may synchronize these at the same time. In most cases, this gives optimal performance. However, if there are many concurrent topology synchronizations, the performance of the Global Manager may be adversely affected. Also, topology synchronizations overall may take longer due to the contention caused by many concurrent threads updating the Global Manager repository.