HA Capabilities and Limitations

The primary hub performs the following essential functions:

During failover, all functions of the primary hub can be temporarily assumed by an HA hub, EXCEPT for communication with UMP, which initiates communication with the primary hub. In most deployments, this limitation is acceptable because:

The next sections illustrate the connections and data flow during normal operation and during failover.

Note: The best way to ensure that UMP can always access the data is to install UIM Server on a Microsoft cluster. If the cluster’s active node fails, the secondary node takes over and primary hub functionality continues with very limited interruption. Data flow, alarms, component management, and data viewing all continue as normal. For information on installing UIM Server on a cluster, see the CA UIM Server Installation Guide.