Rebecca, It doesn't matter. You can run tcpdump on either machine. Save the tcpdump file (use option -s0 to capture the entire packet) and open it with OpenFlow wireshark to see what is wrong. I really recommend to go through OpenFlow Tutorial..
- Masa On May 17, 2012, at 5:15 PM, Rebecca Last Name wrote: > Hi Masa. The tcpdump command should be done on which PC? controller PC or > switch PC? Because dpctl command is done on switch PC to install flow > manually. Am I right? By the way, what is output i should get after tcpdump? > Thank you! > > From: Masayoshi Kobayashi <mkoba...@stanford.edu> > To: Rebecca Last Name <rebecca_chan...@yahoo.com> > Cc: "openflow-discuss@lists.stanford.edu" > <openflow-discuss@lists.stanford.edu> > Sent: Friday, 18 May 2012 2:29 AM > Subject: Re: [openflow-discuss] How to add flow correctly? > > Rebecca, > > correction: > > dpctl --strict del-flows unix:/var/run/dp0 > > will delete all three entries. > > This has to be > dpctl del-flows unix:/var/run/dp0 > (don't use '--strict'). > > For POX, it may be a good idea to first check whether your switch is really > connected to POX or not. > If it is, then tcpdump the controller communication between POX and your > switch to see what is going on > (with OpenFlow wireshark). If you're not familiar with those basic debug > steps, it may be worth going > through OpenFlow Tutorial at > > - Masa > > On May 17, 2012, at 4:02 AM, Rebecca Last Name wrote: > > > Masa, > > Thank you! Yes, I'm using POX. But I don't know how to let POX install flow > > for me. I can make the switch communicate with controller. From monitoring > > wireshark, i can see controller and switch are exchanging tcp packets all > > the time. But when i want to ping host A and host B, they just won't reach > > each other. It says Network host unreachable. Do you know anything to do > > with POX? This is because i'm totally new to everything. Hope you can give > > me more advice regarding install flow through POX. Thank you very much. > > > > Rebecca. > > > > From: Masayoshi Kobayashi <mkoba...@stanford.edu> > > To: Rebecca Last Name <rebecca_chan...@yahoo.com> > > Cc: "openflow-discuss@lists.stanford.edu" > > <openflow-discuss@lists.stanford.edu> > > Sent: Thursday, 17 May 2012 3:32 PM > > Subject: Re: [openflow-discuss] How to add flow correctly? > > > > Rebecca, > > > > `dpctl del-flows` let you delete the flows you installed. For example, > > suppose you have > > three openflow entries. > > 1) in_port=1,dl_dst=00:00:00:00:00:01,actions=output:2 > > 2) in_port=1,actions=output:2 > > 3) in_port=2,actions=output:3 > > > > The command > > dpctl del-flows unix:/var/run/dp0 in_port=1 > > will delete all flow entries that match "in_port=1", i.e., delete both the > > 1st and 2nd entries. > > > > dpctl --strict del-flows unix:/var/run/dp0 in_port=1 > > will delete only the 2nd flow entry (notice "--strict" option). > > > > dpctl --strict del-flows unix:/var/run/dp0 > > will delete all three entries. > > > > dpctl has lot more features. Run `man dpctl` to learn them (or `nroff -man > > dpctl.8 | less`) > > > > And.. you said in your first email that you're using POX. Why you need to > > install flow tables manually? > > (Why not let POX install them?) > > > > - Masa > > > > > > - Masa > > > - Masa _______________________________________________ openflow-discuss mailing list openflow-discuss@lists.stanford.edu https://mailman.stanford.edu/mailman/listinfo/openflow-discuss
