When you start the Failover Manager, it determines the status of each Broker and the running Broker that has the lowest priority (for example, Broker0) is designated as Active. The Failover Manager treats all other Brokers as Standby.
Next, the Failover Manager registers all Active components, that it monitors, to all Brokers. At any given time, all Brokers know the location of all Active components. The information in the Brokers allows the consoles and other clients to attach to the Active processes.
Since the Broker is critical to the Failover System, the Failover Manager periodically verifies the Broker’s operational state.
During a failover, the Failover Manager registers the newly-promoted Broker with the Active components. It switches the Broker in the memory of all Active components to the Broker that is currently active.
All Brokers will list the current set of active domains.
Broker failover scenarios on page 53 describes the failover scenarios for the Broker.