config>test-oam>build-packet
      header 1 create
         ethernet
            src-mac-address AA:BB:CC:DD:EE:FF
            dst-mac-address FF:EE:DD:CC:BB:AA
      header 2 create
         udp
            src-port 12345
            dest-port 54321
      header 3 create
         ipv4
            dscp 0
            src-ipv4-address 11.22.33.44
            dst-ipv4-address 55.66.77.88