When the controller wants to fetch the details of all the group entries installed in the switch, they should send the OFPMP_GROUP_DESC
multipart message (ofp_multipart_request
) to the switch.
To get information about the group entries in switch, the controller should send a multipart request message with the type
field set as OFPMP_GROUP_DESC
. The message format that should be used by the controller to form the multipart request message is defined in the Introduction section in Chapter 5, Handling Multipart Statistics Messages (Part 2).
The body
field should be left empty.
After sending the multipart request message to the switch, the controller should wait for the reply message from the switch. The format of the reply message is described in detail in the Getting the group description using multipart messages recipe in Chapter 6, Handling Multipart State Information Messages (Part 1). Once the controller receives the reply...