On Mon, Dec 10, 2012 at 5:16 PM, Rich Lane <rich.l...@bigswitch.com> wrote: > This action allows the controller to change the destination IP of the > encapsulating packet. It just exposes the existing Linux datapath > functionality. > > Tested by installing a flow with the new action and an output action to a GRE > tunnel port. The resulting packet had the correct destination IP. > > Signed-off-by: Rich Lane <rich.l...@bigswitch.com>
The immediate intention of the new infrastructure in the kernel module was not actually to support this type of operation, it's primarily designed to be consumed by userspace (and to futureproof the interface). As such, I don't think we can just expose it outwards directly without fleshing out the concept. The first and easiest piece is that the userspace/kernel interface should be completely built out before we start adding pieces on top of it. In particular, it should support the receive side and also not encode particular policies into the serialization layer. I sent out a patch to do this a while back. I couldn't apply it at the time since other pieces were missing (which have since been filled in) and haven't had time to update it. Here it is if you want to help get it in: http://openvswitch.org/pipermail/dev/2012-September/021548.html Another issue is that this doesn't help on the receive side, particularly because packets are matched to ports with their associated IP addresses. In general, I'm not sure that current port configuration makes sense in this context. Finally, the kernel interface was designed with the assumption that it is operating in the context of an exact match flow, which is why it contains actual values for things like ToS and TTL. This enables userspace to flexibly implement different policies like inheritance but it makes less sense in the context of general OpenFlow flows. There is a similar difference with how we implement decrement/set IP TTL: in OpenFlow these are explicit actions but in the kernel interface they both map to a single 'set' command since userspace can calculate the right value. I would expect to see a similar difference in reverse here. _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
