[ovs-discuss] why ovs it does not ask the controller

[Ben Pfaff]

On Fri, May 01, 2015 at 03:51:07PM +0900, Minh Nghiem Gia wrote:
> I have a simple question, however I could not find any way to answer is
> "why ovs has no rules, it does not ask the controller". In theory, when a
> new packet comes, if there is no matching found, the switch will ask the
> controller for actions. In fact, I can see the Packet_in message if I use
> mininet to connect to a controller on a different PC.
> What I did is I installed both controller and OVS on the same PC which has
> multiple network interfaces act as ports of OVS. Then I deleted all flow
> rules on the switch (sudo ovs-ofctl del-flows br0) and executed a ping from
> that PC to the gateway. I think the switch must ask the controller, but
> there is no OF messages!

OVS should work the same way in the second case as in the first.  OVS
doesn't know whether the controller is on the same PC or a different
one.