Clients and servers

An introduction to how IBM MQ supports client-server configurations for its applications.

An IBM MQ MQI client is a component that allows an application running on a system to issue MQI calls to a queue manager running on another system. The output from the call is sent back to the client, which passes it back to the application.

An IBM MQ server is a queue manager that provides queuing services to one or more clients. All the IBM MQ objects, for example queues, exist only on the queue manager machine (the IBM MQ server machine), and not on the client. An IBM MQ server can also support local IBM MQ applications.

The difference between an IBM MQ server and an ordinary queue manager is that a server has a dedicated communications link with each client. For more information about creating channels for clients and servers, see Configure distributed queuing.

For information about clients in general, see Overview of IBM MQ MQI clients.

IBM MQ applications in a client-server environment

When linked to a server, client IBM MQ applications can issue most MQI calls in the same way as local applications. The client application issues an MQCONN call to connect to a specified queue manager. Any additional MQI calls that specify the connection handle returned from the connect request are then processed by this queue manager.

You must link our applications to the appropriate client libraries. See Building applications for IBM MQ MQI clients.