Book Image

OpenFlow Cookbook

Book Image

OpenFlow Cookbook

Overview of this book

Table of Contents (17 chapters)
16
Index

Sending a table-status message to the controller

Table-status messages (OFPT_TABLE_STATUS) are sent from the switch to the controller when there is any change in the table status; for example, the number of entries in the table crosses the threshold value, called the vacancy threshold. The switch should send this message only to the controller channel in which the controller requested the switch to send it. The controller can express its interest to receive this event by sending the asynchronous configuration message to the switch. Refer to the Configuring the switch to send a list of asynchronous events the controller channel is interested in recipe in Chapter 2, Symmetric Messages and Asynchronous Messages (Part 2), for the procedure to configure the switch to send a table status message to the controller.

How to do it...

The switch should build an OFPT_TABLE_STATUS message with the following format and send this message to the controllers that have already shown interest in this event...