Fault Tolerant Failovers

Because send notifications are handled in a separate thread when messages are sent asynchronously, it is possible to receive messages out of order after a fault tolerant switch.

For example, consider an application that sends messages A, B, and C. Message A succeeds, Message B fails, but message C succeeds immediately after reconnect to the fault tolerant server. The application may not know message B failed before message C was sent. Message consumers could conceivably receive messages in the order of A, C, B; it is up to the application to appropriately handle this situation.