Neutron/OFAgent/FlowTable

OpenFlow1.3 flow table for OFAgent

WIP implementation: https://github.com/yamt/neutron/tree/ofagent-merge-bridges

• requirements
  • plain OpenFlow 1.3. no vendor extensions.

• todo: VXLAN (same as GRE?)

• legends

xxx: network id  (agent internal use)
yyy: segment id  (vlan id, gre key, ...)
a,b,c: tunnel port  (tun_ofports, map[net_id].tun_ofports)
i,j,k: vm port  (map[net_id].vif_ports[vif_id].ofport)
x,y,z: physical port  (int_ofports)
N: tunnel type  (0 for TYPE_GRE, 1 for TYPE_xxx, ...)
uuu: unicast l2 address

• tables (in order)

   CHECK_IN_PORT
   TUNNEL_IN+N
   PHYS_IN
   LOCAL_IN
   TUNNEL_OUT
   PHYS_OUT
   LOCAL_OUT
   TUNNEL_FLOOD+N
   PHYS_FLOOD
   LOCAL_FLOOD

• CHECK_IN_PORT

  for each vm ports:
     in_port=i, write_metadata(xxx),goto(ARP_PROXY)   // port_bound
  TYPE_GRE
  for each tunnel ports:
     in_port=a, goto(TUNNEL_IN+N)     // setup_tunnel_port
  TYPE_VLAN
  for each physical ports:
     in_port=x, goto(PHYS_IN)
  TYPE_FLAT
     in_port=x, goto(PHYS_IN)
  default drop

• TUNNEL_IN+N (per tunnel types) tunnel -> network

  TYPE_GRE
  for each networks:  // _provision_local_vlan_tunnel
     // don't goto(TUNNEL_OUT) as it can create a loop with meshed tunnels
     // what to do when using multiple tunnel types?
     tun_id=yyy, write_metadata(xxx),goto(PHYS_OUT)

  default drop

• PHYS_IN // for vlan and flat

  TYPE_VLAN
  for each networks:
     vlan_vid=present|yyy, write_metadata(xxx),pop_vlan,goto(TUNNEL_OUT)

  TYPE_FLAT
     // XXX vlan_vid=none check necessary??  it's what OVS agent does.
     vlan_vid=none, write_metadata(xxx),pop_vlan,goto(TUNNEL_OUT)

  default drop

• LOCAL_IN
  • todo: local arp responder

  default goto(next_table)

• TUNNEL_OUT

  TYPE_GRE
  // _add_fdb_flow (!FLOODING_ENTRY)
  metadata=xxx,eth_dst=uuu  set_tunnel(yyy),output:a

  default goto(next table)

• PHYS_OUT
  • todo: learning and/or l2 pop

  for each known destinations:
      TYPE_VLAN
      metadata=xxx,eth_dst=uuu  push_vlan,set_field:present|yyy->vlan_vid,output:a
  default goto(next table)

• LOCAL_OUT
  • todo: learning and/or l2 pop

  for each known destinations:
     metadata=xxx,eth_dst=uuu output:i
  default goto(next table)

• TUNNEL_FLOOD+N. (per tunnel types)

  network -> tunnel/vlan
  output to tunnel/physical ports
  "next table" might be LOCAL_OUT
  TYPE_GRE
  for each networks:  // _add_fdb_flow (FLOODING_ENTRY)
     metadata=xxx, set_tunnel(yyy),output:a,b,c,goto(next table)

  default goto(next table)

• PHYS_FLOOD

  TYPE_VLAN
  for each networks:
     metadata=xxx, push_vlan:0x8100,set_field:present|yyy->vlan_vid,output:x,y,z,goto(next table)
  TYPE_FLAT
  for each networks:
     metadata=xxx, output:x,y,z,goto(next table)
  default goto(next table)

• LOCAL_FLOOD
  • todo: learning and/or l2 pop

  for each networks:
     metadata=xxx, output:i,j,k  // port_bound
  default drop

• references
  • similar attempts for OVS agent https://wiki.openstack.org/wiki/Ovs-flow-logic
    • we use metadata instead of "internal" VLANs
    • we don't want to use NX learn action