Sounds about right. If you're not altering the incoming packet at all, I think this is probably very close to:
po = ofp_packet_out(data = event.data, action = ofp_action_output(port = out_port)) core.openflow.sendToDPID(dpid, po) ... where ... "event" is the PacketIn event with the packet you want to resend "dpid" is the DPID of the destination switch "out_port" is the port on "dpid" you want to send out of -- Murphy On Jul 8, 2013, at 9:29 PM, Small, Christopher wrote: > A little background on what Kavit is trying to do here is to build a > tunneling mechanism through the controller for a (very small!) number of > packets between hosts connected on two different OF switches connected to the > same controller. > The application is essentially just a learning switch except: > 1) It builds a global L2 table spanning all connected switches that includes > DPID as well as MAC and port for all learned MAC addresses > 2) When a Multicast DNS packet is sent as a Packetin to the controller the > controller sends the received packet as a PacketOut to a different switch > based upon a DB lookup of "paired" source and dest MACs. It uses the global > L2 table to find the DPID of the dest MAC. > I took a quick look at the ofp_packet_out class in > pox/openflow/libopenflow_01.py and it looks like probably the easiest way to > do this is to use the ofp_packet_out to build a new packet and then pack the > data from the Packetin into the new PacketOut. > What Kavit is currently doing is sending the packet received by the > controller back out directly using sendToDPID. > --Chris Small > > ====== > > I think sendToDPID() just doesn't do what you think it does. It is for > sending OpenFlow commands to a switch -- the same as connection.send(), > except it looks up the connection for you based on DPID. I believe you're > trying to use it to send a packet out of some port on a switch. There's an > obvious piece of information missing here -- sendToDPID takes a DPID, but how > would it know which port you want to send the packet out of? > > What you need to do is create an ofp_packet_out() which has an output action > to the appropriate port and the data you want to send as the 'data' > attribute. This is similar to the flood() function in l2_learning which is in > your source. There are even closer examples in other modules (e.g., > misc.dhcpd). Then send *that* using sendToDPID(), or in your case -- just > use connection.send(). > > -- Murphy > > On Jul 5, 2013, at 12:52 PM, Kavit Shah wrote: > > > Command line with log, my code and screen shot of the wireshrak are > > attached in the text and png files. > > > > I am using HP Pro curve switch, i think it supports OF 1.0 spec. > > > > > > ##################################### > > ##################################### > > > > Important part of my code in the attached file > > > > ##################################### > > ##################################### > > > > Questions: > > > > 1) sendToDPID function is not working the way I expect it to work. > > According to me if that function works I should see packet out in wireshark. > > > > 2) Am I extracting dpid of the switch correctly ? > > > > 3) What is the reason for getting an error while switch connects to the POX > > controller ? > > > > ERROR:openflow.of_01:[00-16-b9-ce-2f-40|800 1] OpenFlow Error: > > [00-16-b9-ce-2f-40|800 1] Error: header: > > [00-16-b9-ce-2f-40|800 1] Error: version: 1 > > [00-16-b9-ce-2f-40|800 1] Error: type: 1 (OFPT_ERROR) > > [00-16-b9-ce-2f-40|800 1] Error: length: 20 > > [00-16-b9-ce-2f-40|800 1] Error: xid: 7 > > [00-16-b9-ce-2f-40|800 1] Error: type: OFPET_BAD_REQUEST (1) > > [00-16-b9-ce-2f-40|800 1] Error: code: OFPBRC_BAD_TYPE (1) > > [00-16-b9-ce-2f-40|800 1] Error: datalen: 8 > > [00-16-b9-ce-2f-40|800 1] Error: 0000: 01 12 00 08 00 00 00 07 > > ........ > > > > > > <sendToDPID_question.txt><sendToDPID_wireshark.png>_______________________________________________ > > mininet-discuss mailing list > > mininet-discuss at lists.stanford.edu > > https://mailman.stanford.edu/mailman/listinfo/mininet-discuss >
