Hello everyone.
I'm using MIninet 2.0, POX and Open vSwitch, and I try to implement NAT/PAT
function in switch. But I faced with one problem: when I send ofp_flow_mod
message, like this:
ip_packet = packet.payload
tcp_packet = ip_packet.payload
new_src_port = random.randint(4096, 65533)
back_msg = of.ofp_flow_mod()
back_msg.cookie = 12
back_msg.match.in_port = port
back_msg.match.nw_dst = IPAddr("10.0.2.1")
back_msg.match.tp_dst = new_src_port
back_msg.actions.append(of.ofp_action_output(port = event.port))
back_msg.actions.append(of.ofp_action_nw_addr.set_dst(ip_packet.srcip))
back_msg.actions.append(of.ofp_action_tp_port.set_dst(tcp_packet.srcport))
back_msg.idle_timeout = 120
self.connection.send(back_msg)
and then I check flow with command:
ovs-ofctl dump-flows tcp:127.0.0.1:6635
And the only flow with cookie = 12 has only 1 match field instead of 3, that I
specify in match structure, but all actions are correct:
cookie=0xc, duration=5.999s, table=0, n_packets=6, n_bytes=1637,
idle_timeout=120,in_port=2 actions=output:1,mod_nw_dst:10.0.1.1,mod_tp_dst:57830
I've added log.debug message, that could help to find problem, but it looks ok:
log.debug('Back message with match structure: port - %i, IP-dest - %s,
TCP-port dst - %i' % (port, back_msg.match.nw_dst, back_msg.match.tp_dst))
DEBUG:ext.lab_4:Back message with match structure: port - 2, IP-dest -
10.0.2.1, TCP-port dst - 51920
I send one more ofp_flow_mod message in the same event handler, but I use
ofp_match.from_packet() method and it works fine.
Thanks,
Alex.
