Application servers running on WebSphere® Application Server and queue managers running on WebSphere MQ can connect to each other when neither of them are clustered. However, this setup can be vulnerable to failure.
The WebSphere MQ transport type for the connection is specified as "client". A "client" connection is used when the application server and queue manager are running on different hosts. This is a TCP/IP network connection that is used to communicate with the queue manager. A client connection is also known as "socket attach".
The following figure shows an application server and a queue manager running on different hosts.
You can improve availability for this topology by using, for example, High Availability Cluster Multi-Processing (HACMP) to restart the failed component automatically.
The transport type for the connection is specified as "bindings". A "bindings" connection is used when the application server and the queue manager are running on the same host. This is a cross-memory connection that is used to communicate with a queue manager. A bindings connection is also known as "call attach".
The following figure shows a application server and a queue manager running on the same host.
The availability constraints for this topology are similar to the previous one. However, in some configurations bindings mode is faster and more processor efficient than client mode because the amount of processing is reduced.