<div dir="ltr"><div>Thanks a lot! <br></div><div>OVS version 2.9.0 was installed along with Mininet emulator. I've already tried to update OVS to v2.10.1, but Mininet then met some issues in creating the emulation. Anyway, there was the same error with the newest OVS version.</div><div>I have created a PCAP file for you. Kindly please have a look at the packets no. 89 and 90, these are the request and error reply packets.<br></div><div><br></div><div>Thank you for your time.<br></div><div>Regards,<br></div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"> Jozef Valko.</div></div></div></div><br><br><div class="gmail_quote"><div dir="ltr">ne 11. 11. 2018 o 21:35 Ben Pfaff <<a href="mailto:blp@ovn.org">blp@ovn.org</a>> napísal(a):<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On Sun, Nov 11, 2018 at 09:12:03PM +0100, Jozef Valko wrote:<br>
> Hello all,<br>
> I am developing an SDN application using Ryu and Mininet. My goal is to<br>
> develop security module on the top of Ryu controller. Therefore, I need a<br>
> regular statistics update from the forwarders which are OVS bridges. For<br>
> this purpose I am using OFPFlowStatsRequest function provided by Ryu<br>
> parser. Below is the function which I am using:<br>
> [image: image.png]<br>
> This function runs in separate thread and sends the request every 10<br>
> seconds.<br>
> When I use this function with OpenFlow14 everything is fine, the controller<br>
> receives flow stats from the forwarder. But when I try to trigger this<br>
> function using OpenFlow15, the following error shows in the controller<br>
> window:<br>
> [image: image.png]<br>
> I tried to google this issue, searched in the specification and Ryubook but<br>
> I did not find any solution. Because Ryu doesn't crash, I suppose that this<br>
> is OVS-related issue.<br>
> The only difference between requests in OF14 and OF15 is the value of the<br>
> field 'type'. In case of OF14 it is 1 and in case of OF15 it is 17. Here is<br>
> the request before sending (OF15):<br>
> [image: image.png]<br>
> What can be an issue? How to properly request flow statistics from the OVS<br>
> forwarders using Ryu and OpenFlow15?<br>
> Versions of the applications:<br>
> Mininet - 2.3.0d4<br>
> Ryu - ryu-manager 4.29<br>
> OVS - ovs_version: "2.9.0"<br>
> <br>
> PortStatsRequest function is working nicely in both OF14 and OF15.<br>
<br>
OVS doesn't fully support OpenFlow 1.5 and does not enable it by<br>
default, so I suppose that you turned it on yourself. That is fine--we<br>
are pleased to hear about problems with protocol versions that are not<br>
yet complete. Also, I don't see any problems with OF1.5 flow stats and<br>
it seems to work OK in my own simple test case with ovs-ofctl.<br>
<br>
However, for testing incomplete protocol versions, one should use the<br>
latest version of Open vSwitch. Please try the latest release v2.10.1<br>
or what one can find on master.<br>
<br>
Alternatively, if you can provide a hex dump of the message that Ryu is<br>
sending OVS (or otherwise some kind of exact representation), I can test<br>
that for you.<br>
</blockquote></div></div>