Book Image

OpenFlow Cookbook

Book Image

OpenFlow Cookbook

Overview of this book

Table of Contents (17 chapters)
16
Index

Configuring the switch to send a list of asynchronous events the controller channel is interested in

The OpenFlow specification provides a mechanism for the controller to inform a switch about the list of asynchronous events that the controller/controller channel is interested in. This is achieved by sending a "Set Asynchronous Configuration message" (OFPT_SET_ASYNC) to the switch. This is mostly useful when a switch is managed by multiple controllers and every controller wants to process only a subset of events. Using this feature, different controllers can subscribe to receive different notification messages from switches, resulting in the controller load balancing.

How to do it...

The message format to be used to send the OFPT_SET_ASYNC message is as follows:

/* Asynchronous message configuration. */
struct ofp_async_config {
struct ofp_header header; /* OFPT_GET_ASYNC_REPLY or
                           * OFPT_SET_ASYNC. */
/* Async config Property list - 0 or more */
struct...