This behavior would be best described as under-specified in the OpenFlow spec. The OpenFlow reference implementation makes the same modifications to the one you're seeing in OVS. It would probably be worth bringing up on the openflow-spec mailing list, if you'd like to see this behavior changed/better defined.
--Justin On Feb 17, 2011, at 7:21 PM, Derek Cormier wrote: > Yes, that's true. I though about using the cookie field, but I want to leave > that open for a future use. My main concern is that it goes against the > OpenFlow protocol. > > - Derek > > On 02/18/2011 12:05 PM, Justin Pettit wrote: >> What about flow cookies? They're 64-bit identifiers that exist in both the >> Flow Mod and Flow Removed messages. >> >> --Justin >> >> >> On Feb 17, 2011, at 6:50 PM, Derek Cormier wrote: >> >>> Sure, let me explain the problem. I am maintaining a copy of the flows in >>> memory outside of the controller (Nox). When a flow is removed, I need to >>> remove it from the stored flows. However, if the wildcards are not exact in >>> the removed message, I cannot identify exactly which flow it is. I could >>> have a flow with those extra fields set to 0 and I would think it's that >>> flow being deleted, when it's really a different one. >>> >>> Thanks, >>> - Derek >>> >>> On 02/18/2011 11:40 AM, Justin Pettit wrote: >>>> Hi, Derek. I just wanted to let you know that we're still discussing how >>>> to best handle this. How difficult is it from your perspective if OVS >>>> continued to behave in this manner? There was a time when this >>>> normalization was more important from a performance perspective than it is >>>> now, so we may be able to either stop normalizing or at least store the >>>> original wildcards. However, OVS has behaved this way for a long time, >>>> and we haven't heard other application writers have issues with it. I >>>> understand how it could be confusing, though. >>>> >>>> --Justin >>>> >>>> >>>> On Feb 16, 2011, at 1:39 AM, Justin Pettit wrote: >>>> >>>>> Okay, that makes a bit more sense. My guess is that if you look in >>>>> ovs-vswitchd's logs, you'll see some messages about "normalization >>>>> changed ofp_match". Internally, we're clearing those other wildcard >>>>> bits, since they're meaningless for non-IP/ARP flows (such as your flow >>>>> definition with ethertype of 5). I'll talk with Ben about how we want to >>>>> handle this from an OpenFlow-compatiblity standpoint tomorrow. >>>>> >>>>> --Justin >>>>> >>>>> >>>>> On Feb 16, 2011, at 12:51 AM, Derek Cormier wrote: >>>>> >>>>>> Great. I also made a mistake about the field. It was dl_type, not >>>>>> dl_src. It actually works fine for dl_src. >>>>>> >>>>>> - Derek >>>>>> >>>>>> On 02/16/2011 05:36 PM, Justin Pettit wrote: >>>>>>> No problem. Most of us are subscribed to both. :-) We'll take a look >>>>>>> at it in the morning, California time. I don't expect it will be a >>>>>>> difficult fix. >>>>>>> >>>>>>> Thanks for reporting it. >>>>>>> >>>>>>> --Justin >>>>>>> >>>>>>> >>>>>>> On Feb 16, 2011, at 12:26 AM, Derek Cormier wrote: >>>>>>> >>>>>>>> Now that I think about it, this should have been posted to the dev >>>>>>>> board. Sorry about that! >>>>>>>> >>>>>>>> - Derek >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> discuss mailing list >>>>>>>> discuss@openvswitch.org >>>>>>>> http://openvswitch.org/mailman/listinfo/discuss_openvswitch.org >>>> >> >> > _______________________________________________ discuss mailing list discuss@openvswitch.org http://openvswitch.org/mailman/listinfo/discuss_openvswitch.org
