Message Bridge and Foriegn Server, When to use what.

Foreign Server:

Foreign JMS server definitions are an administratively configured symbolic link between a JNDI object in a remote JNDI directory, such as a JMS connection factory or destination object, and a JNDI name in the JNDI name space for a stand-alone WebLogic Server or a WebLogic cluster. They can be configured using the Administration console, standard JMX MBean APIs, or programmatically using scripting. See Simplified Access to Foreign JMS Providers.

When is it best to use a Foreign JMS Server Definition?

For this release, a Foreign JMS Server definition conveniently moves JMS JNDI parameters into one central place. You can share one definition between EJBs, servlets, and messaging bridges. You can change a definition without recompiling or changing deployment descriptors. They are especially useful for:

• Any message driven EJB (MDB) where it is desirable to administer standard JMS communication properties via configuration rather than hard code them into the application's EJB deployment descriptors. This applies even if the MDB's source destination isn't remote.

• Any MDB that has a destination remote to the cluster. This simplifies deployment descriptor configuration and enhances administrative control.

• Any EJB or servlet that sends or receives from a remote destination.

• Enabling resource references to refer to remote JMS providers. See Using EJB/Servlet JMS Resource References.

  
  

  Message Bridge:

  
  

  Messaging bridges are administratively configured services that run on a WebLogic server. They automatically forward messages from a configured source JMS destination to a configured target JMS destination. These destinations can be on different servers than the bridge and can even be foreign (non-WebLogic) destinations. Each bridge destination is configured using the four common properties of a remote provider:

  • The initial context factory.

  • The connection URL.

  • The connection factory JNDI name.

  • The destination JNDI name.

  Messaging bridges can be configured to use transactions to ensure exactly-once message forwarding from any XA capable (global transaction capable) JMS provider to another.

  When should I use a messaging bridge?

  Typically, messaging bridges are used to provide store-and-forward high availability design requirements. A messaging bridge is configured to consume from a sender's local destination and forward it to the sender's actual target remote destination. This provides high availability because the sender is still able to send messages to its local destination even when the target remote destination is unreachable. When a remote destination is not reachable, the local destination automatically begins to store messages until the bridge is able to forward them to the target destination when the target becomes available again.