File name: cjj_common_issues_for_bus_configs.html

Common issues with all bus configurations


When planning a service integration bus configuration, consider the following points:

The volume of messages that a bus has to handle. Depending on the volume of messages anticipated, you might have to adjust the high message threshold setting for a bus or messaging engine.

The transport chain to be used for communication between messaging engines.

Whether bus security is required. When bus security is enabled, access to the bus itself and to all destinations on the bus must be authorized. If you enable bus security, you might also want to define aliases for authenticating messaging engines and mediations accessing the bus. A single version bus does not require an authentication alias. However, if you create a mixed-version bus define an inter-engine authentication alias for a WebSphere® Application Server Version 6 or Version 6.1 bus member, to enable it to establish trust with the other bus members of later versions.

Choose bus names that are compatible with the WebSphere MQ queue manager naming restrictions. We cannot change a bus name after the bus is created, which means that you can only interoperate with WebSphere MQ in the future if you use compatible names.

When you name your buses, ensure that the names are unique because you cannot connect two buses with the same name. For example, you cannot connect two buses with the same name in any of the following ways:

Destinations

Decide on the number and type of destinations, mediations, destination routing paths, and qualities of service for the destination for the configuration. For point-to-point messaging you define bus destinations as queues, whereas for publish/subscribe messaging you define bus destinations as topic spaces.

For point-to-point messaging only, you select one bus member as the assigned bus member that is to hold messages for the queue. This action automatically defines a queue point for each messaging engine in the assigned bus member.

We can also define alias destinations to provide a level of indirection between applications and the underlying target bus destinations. Applications interact with the alias destination, so you can change the target bus destination without changing the application.

You should decide how you want to use the bus destinations as you can configure a bus destination to prevent producers sending messages to the destination, or consumers receiving messages from the destination.

Message persistence

The reliability quality of service for messages on a destination has implications for performance and the amount of space required for a message store. Higher levels of reliability impact performance and increase the space a message store requires, because fewer messages are discarded.

When planning a message store configuration, remember that each messaging engine has a single message store, which can be either a file store or a data store. Larger messages increase the space that a message store requires. If you use a data store, the default database system for the data store is Apache Derby Version 10.3. However, you might want to use a different system, such as DB2. We can select different data store configurations depending on your requirements

Application environment

An application attaches as a client to a messaging engine on the bus, either by an in-process call or across a network by using a remote client. A remote client can run in either the Java EE application client environment or the Java EE application server environment. Various transport chains can be used.

Application connections

The way that a messaging engine is selected, and the mechanism that an application uses to reach it, is configured on a JMS connection factory. Decide which messaging engines the applications should connect to and on the transport chain to be used.

WebSphere MQ client links

WebSphere MQ client links allow JMS clients developed for WAS Version 5.1