Deployment Guide

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There is no body required for this API command so you can then hit the Send button to send the command to
the REST API. The output from the controller is captured and a status shown as seen below where you see
“200 OK” as the status of the call. If this call fails there will be an error code where the “200 OK” is, and error
status information shown below that, otherwise it returns the list of datapath ID’s that the controller knows
about. In this case since there is only one controller connected, it shows us our switch datapath ID. This
datapath ID will be used for all of the other communications with the switch via the Ryu controller for actions
such as adding, modifying and deleting flows, retrieving error and counter status and establishing default switch
behaviors.
If you can read the switch node ID from the controller then you have established communications with the
controller and can begin programming it for flows. For a continued example of setting up a simple end to end
traffic L2 bridging flow, see Appendix B.