Sun Java System Message Queue 4.1 Technical Overview

Handling Destinations in the Event of Connection or Broker Failure

Table 4–2 explains how different kinds of destinations are replicated and deleted in a cluster.

Table 4–2 Handling Destinations in a Cluster

Destination 

Propagation, and Deletion 

Admin-created 

When the destination is created it is propagated in the cluster, and each broker stores information about the destination persistently. 

The destination is destroyed when the administrator explicitly deletes it. 

Using the conventional cluster model, if there is a master broker, a record of the creation and deletion is stored in the master broker to allow brokers in the cluster to synchronize state information. 

Using the high availability cluster model, information synchronized using the shared persistent store. 

Temporary 

When the destination is created, it is propagated around the cluster. 

If the consumer associated with the temporary destination is allowed to reconnect, the destination is persistently stored on the consumer’s home broker. Otherwise, the destination is never stored. In this case, if the consumer loses its connection, the destination is deleted on all brokers. 

If the consumer’s home broker crashes and the consumer is allowed to reconnect, temporary destinations associated with this consumer are monitored. If the consuming client does not reconnect within a specific period of time, it is assumed that the client has failed and the destination is deleted. 

Auto-created 

When a producer is created and a destination does not exist, the destination is created on the producer’s home broker. 

When a consumer is created for a destination that does not exist, information about the consumer and the destination is propagated across the cluster. 

An auto-created destination can be explicitly deleted by an administrator, or it can be automatically deleted 

  • By each broker when there have been no consumers or messages for a given period of time.

  • By each broker, when the broker restarts and there are no messages for that destination.