Yes, I agree that write_metadata is limited; it's defined by OpenFlow that way so we can't easily change it. Using "load" is a better approach.
On Fri, Nov 13, 2015 at 01:46:37AM +0000, Chao Hu wrote: > Hi Ben, > > Thanks for your reply! > Seems the action "write_metadata" is not allowed to set before "Controller", > so I tried to use " load:****->NXM_NX_REG*" instead, to pass any data to > controller and it worked. > I think the usage of metadata is very limited if so. > Pls correct me. > > Thanks > Chao > > -----Original Message----- > From: Ben Pfaff [mailto:[email protected]] > Sent: Tuesday, August 25, 2015 1:37 AM > To: Chao Hu > Cc: [email protected] > Subject: Re: [ovs-discuss] a problem about passing metadata in packet-in > > On Fri, Aug 21, 2015 at 07:51:15PM +0000, Chao Hu wrote: > > I'm trying to pass metadata from OVS switch to controller but always get 0. > > Anything wrong with my steps? > > My test environment is: > > OVS: 2.0.2 > > OVS-controller: 2.3.1 > > OF: OpenFlow1.3 > > > > My test steps are: > > > > 1. Make OVS-controller to send a OFPRAW_NXT_SET_PACKET_IN_FORMAT > > message to OVS switch, to set the packet-in-format to NXM (Nicira > > Extended). As I captured, it's a OFPT_EXPERIMENTER packet and the > > content is exactly the same with the packet of running "ovs-ofctl > > monitor -P nxm tcp:myip:6653 -O OpenFlow13". Seems Switch do nothing > > after received this packet. > > This is a bad idea. The OpenFlow 1.3 packet-in format is already extensible > so there should be no need to change it. > > > 2. Add a flow to OVS switch: > > cookie=0x0, duration=28.019s, table=0, n_packets=0, n_bytes=0, > > in_port=2 actions=CONTROLLER:65535,write_metadata:0x11/0xffff > > > > 3. OVS switch send the packet-in traffic to controller when it > > matches above flow, but metadata is 0. > > The actions above set the metadata after sending the packet to the controller. _______________________________________________ discuss mailing list [email protected] http://openvswitch.org/mailman/listinfo/discuss
