May be I am misinterpreting Wireshark , but I see that the LLDP packet is received on the sender switch , but on a different port.
Example:Switch (DpID:3 ) is instructed to send a LLDP packet on port 2 . That would be the first OFP_LLDP packet out message in the below screenshot. the second row, is a packet in message, received on port 3 of the switch (dpid 3) ,with the LLDP packet as payload . I did look for other packets captured too, but I see that LLDP packet sent out from one port of a switch is received and passed to the controller via another port, but not by another switch. Am I missing something obvious or did not understand properly here? Cheers! Durga On Wed, May 21, 2014 at 7:14 AM, Murphy McCauley <murphy.mccau...@gmail.com>wrote: > > On May 20, 2014, at 1:51 AM, durga <c.vijaya.du...@gmail.com> wrote: > > Hello All, > > This question is w.r.t LLDP . Upon bootup - controller instructs switch to > 'packet-out' LLDP protocol on its interface. Lets say SW1, P1. If the > topology is SW1.P1<—> SW2.P2, I would expect SW2 to send an OF message to > the controller with payload of the LLDP received from SW1.P1. That way the > controller can establish that SW1.P1 is indeed connected to SW2.P1. > > > Right. > > But when I run openflow/discovery.py , I notice that SW2.P1 is sending an > LLDP packet with its own details iw SW2.P1 and not SW1.P1 , > > > What makes you think that? It shouldn't be the case. > > may be my understanding is incorrect, but how exaclty is the controller > able to conclude SW1.P1 is connected to SW2.P1? > > controller logs: > > INFO:openflow.of_01:[None 6] closed > INFO:openflow.of_01:[00-00-00-00-00-01 7] connected > DEBUG:discovery:Installing flow for 00-00-00-00-00-01 > INFO:openflow.of_01:[00-00-00-00-00-02 8] connected > DEBUG:discovery:Installing flow for 00-00-00-00-00-02 > INFO:discovery:link detected: 00-00-00-00-00-01.2 -> 00-00-00-00-00-02.2 > INFO:discovery:link detected: 00-00-00-00-00-02.2 -> 00-00-00-00-00-01.2 > > > screenshot: > > > > Cheers! > Durga > > >
