Message flow control

Message flow control is a task that involves the setting up and maintenance of message routes between queue managers. It is important for routes that multi-hop through many queue managers. This section describes how we use queues, alias queue definitions, and message channels on the system to achieve message flow control.

You control message flow using a number of techniques that were introduced in Configure distributed queuing. If your queue manager is in a cluster, message flow is controlled using different techniques, as described in Message flow control. If your queue managers are in a queue sharing group and intra-group queuing (IGQ) is enabled, then the message flow can be controlled by IGQ agents. These agents are described in Intra-group queuing.

We can use the following objects to achieve message flow control:

  • Transmission queues
  • Message channels
  • Remote queue definition
  • Queue manager alias definition
  • Reply-to queue alias definition

The queue manager and queue objects are described in Object types. Message channels are described in Distributed queuing components. The following techniques use these objects to create message flows in the system:

  • Put messages to remote queues
  • Routing by way of particular transmission queues
  • Receive messages
  • Passing messages through the system
  • Separate message flows
  • Switching a message flow to another destination
  • Resolving the reply-to queue name to an alias name


Note

All the concepts described in this section are relevant for all nodes in a network, and include sending and receiving ends of message channels. For this reason, only one node is illustrated in most examples. The exception is where the example requires explicit cooperation by the administrator at the other end of a message channel.

Before proceeding to the individual techniques, it is useful to recap on the concepts of name resolution and the three ways of using remote queue definitions. See Distributed queuing and clusters.

Parent topic: IBM MQ distributed queuing techniques


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