Hi Ben, Thank you for your reply. And I am sorry that I post this question twice. I just clicked Send but there was nothing happened so I just re-click it again. Really sorry for that.
*ovs-appctl ofproto/trace *gives me the answer. mininet> *sh ovs-ofctl add-flow s1 in_port=1,actions=output:1 -O OpenFlow13* mininet> mininet> sh ovs-appctl ofproto/trace s1 in_port=1 Flow: metadata=0,in_port=1,vlan_tci=0x0000,dl_src=00:00:00:00:00:00,dl_dst=00:00:00:00:00:00,dl_type=0x0000 Rule: table=0 cookie=0 in_port=1 OpenFlow actions=output:1 *skipping output to input port* Final flow: unchanged Relevant fields: skb_priority=0,in_port=1,dl_type=0x0000,nw_frag=no *Datapath actions: drop* And actually, there is one specific port reserved for output to input port ,* no need* to use* output:1*, below is information about this port in *openflow-spec-v1.3.0* *OFPP_IN_PORT = 0xfffffff8, /* Send the packet out the input port. This reserved port must be explicitly used in order to send back out of the input port. */ * So I just changed the *actions=output:1* into *actions=in_port*, and it works! mininet> *sh ovs-ofctl add-flow s1 in_port=2,actions=in_port -O OpenFlow13* mininet> mininet> mininet> sh ovs-appctl ofproto/trace s1 in_port=2 Flow: metadata=0,in_port=2,vlan_tci=0x0000,dl_src=00:00:00:00:00:00,dl_dst=00:00:00:00:00:00,dl_type=0x0000 Rule: table=0 cookie=0 in_port=2 *OpenFlow actions=IN_PORT* Final flow: unchanged Relevant fields: skb_priority=0,in_port=2,dl_type=0x0000,nw_frag=no *Datapath actions: 6* Thanks again! Shawn Lin On Wed, Jul 13, 2016 at 12:12 PM, Ben Pfaff <b...@ovn.org> wrote: > On Mon, Jul 11, 2016 at 09:41:36PM +0800, Shawn Lin wrote: > > I am trying to use OpenvSwitch to exchange the source IP address and the > > destination IP address of a packet, and then forward this packet out to a > > host. > > > > I do this test in *Mininet(2.2.1) *and *OpenvSwitch(2.0.2)*, And below is > > the command: > > > > Topology in Mininet is quite simple, > > *h1-s1-h2* > > > > I use this command to add the flow. > > *mininet> sh ovs-ofctl add-flow s1 > > > dl_type=0x0800,dl_type=0x0800,nw_dst=10.0.0.2,actions=mod_dl_src:00:00:00:00:00:02,mod_dl_dst:00:00:00:00:00:01,mod_nw_src:10.0.0.2,mod_nw_dst=10.0.0.1,output:1 > > -O OpenFlow13* > > > > And then I could see the result when I show flows in the switch s1, > > > > *mininet>* *sh ovs-ofctl dump-flows s1 -O OpenFlow13* > > OFPST_FLOW reply (OF1.3) (xid=0x2): > > > > > > > > * cookie=0x0, duration=418.133s, table=0, n_packets=1813, > n_bytes=2731190, > > ip,nw_dst=10.0.0.2 > > > actions=mod_dl_src:00:00:00:00:00:02,mod_dl_dst:00:00:00:00:00:01,mod_nw_src:10.0.0.2,mod_nw_dst:10.0.0.1,output:1 > > * > > * In my understanding, this flow would change the packets' src IP, dst > IP, > > src Mac, dst Mac, and then forward it out port 1 which is s1-eth1. * > > > > cookie=0x2b0000000000000f, duration=2982.739s, table=0, n_packets=1, > > n_bytes=42, priority=2,in_port=1 actions=output:2,CONTROLLER:65535 > > > > > > cookie=0x2b0000000000000e, duration=2982.739s, table=0, n_packets=1, > > n_bytes=42, priority=2,in_port=2 actions=output:1,CONTROLLER:65535 > > > > > > cookie=0x2b0000000000000f, duration=2986.774s, table=0, n_packets=0, > > n_bytes=0, priority=100,dl_type=0x88cc actions=CONTROLLER:65535 > > > > > > cookie=0x2b0000000000000f, duration=2986.774s, table=0, n_packets=0, > > n_bytes=0, priority=0 actions=drop > > > > And then in terminal, I use tcpdump to catch the packets through s1-eth1, > > *tcpdump -i s1-eth1 -w result.pcap* > > > > I scan all packets and find that these packets are all with *src IP > > 10.0.0.1, and dst IP 10.0.0.2.* > > At the same time, the *n_bytes* in flow shows that this flow has been > hit. > > > > So Am I doing some wrong configuration? Or which version of OVS support > > this feature? Any suggestions or comments are welcomed! > > Every version of OVS ever released supports this feature. Your flow > looks OK to me. It's hard to guess what's going wrong. You might want > to use "ovs-appctl ofproto/trace" or "ovs-dpctl dump-flows" to try to > peer deeper into what's going on. >
_______________________________________________ discuss mailing list discuss@openvswitch.org http://openvswitch.org/mailman/listinfo/discuss
