Hi Murphy, Thanks for the reply.
No, I am not using NOX (Yes indeed - I should have gone to the OpenFlow mailing list. I will.). This is a new controller which is still under development. I am sure the controller does not send a features-request (because that part has not been coded yet). So, yes, the controller is "out of spec" for now. So I am sure that the features request comes from "ifprotocol" (which is not a controller, as far as I know). It appears to send it "proactively" as you say, and this is exactly what seemed surprising (and frankly incorrect) to me. Also, I am using the OpenFlow dissector in wireshark, so I quite sure that the list of packets is accurate in the summary below (i.e. I did not miss packets because there multiple OpenFlow packets in a single TCP packet). On Wed, Jan 11, 2012 at 3:59 PM, Murphy McCauley <jam...@nau.edu> wrote: > I can't speak as to the particulars of the reference switch (you might try > one of the OpenFlow mailing lists). > > However, the spec does state that part of the handshake sequence is that the > controller sends a features request when a connection is established. I > don't see this in your sequences of messages below. NOX should do this. Are > you using NOX? If so, is it possible you missed this message (remember that > multiple OpenFlow messages can be in the same packet, so it is possible it's > in packet #4 along with the HELLO or something -- you'll have to look at the > detail view of the packet, not just the summary line)? > > If the message really isn't there, I suppose it's possible that ofprotocol > does this proactively, but in this case I believe your controller is out of > spec. > > -- Murphy > > On Jan 11, 2012, at 6:00 AM, Cayle Spandon wrote: > >> Are OpenFlow controllers expected to process unsolicited feature-reply >> messages? >> >> I am running the following setup: >> >> controller ----- ofprotocol ----- ofdatapath >> >> Using wireshark I see the following sequence of messages: >> >> #1 ofprotocol -> ofdatapath : hello >> #2 ofprotocol -> controller : hello >> #3 ofdatapath -> ofprotocol : hello >> #4 controller -> ofprotocol : hello >> #5 ofprotocol -> ofdatapath : features-request >> #6 ofdatapath -> ofprotocol : features-reply >> #7 ofprotocol -> controller : features-reply >> >> This means that the controller gets a features-reply even though it >> never sent a features-request. >> >> It appears that ofprotocol originates the features-request to the >> switch (which is somewhat surprising because I thought it was supposed >> to be a dumb pass-through) and the forwards the features-reply to the >> controller. >> _______________________________________________ >> nox-dev mailing list >> nox-dev@noxrepo.org >> http://noxrepo.org/mailman/listinfo/nox-dev > _______________________________________________ nox-dev mailing list nox-dev@noxrepo.org http://noxrepo.org/mailman/listinfo/nox-dev
