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Network Testing and Emulation Solutions

Create Python Scripts To Test Generic Traffic

Goal: Create a script to test Generic traffic using Realm

Using the library we will write a script that will allow us to automate the creation of stations and generic cross connects. We will also be able to start and stop traffic over the cross connects using the script. Station and Cross Connect creation is covered in the Realm Scripting Cookbook. Requires LANforge 5.4.2.
  1. Creating The Profile

    1. We will use the factory method self.local_realm.new_generic_cx_profile() to create our profile object.
    2. After we have done this we can set a few variables for our traffic:
      1. gen_cx_profile.type will determine the type of command to execute.
        Example: self.cx_profile.type = "lfping"
      2. gen_cx_profile.dest is the destination IP address for the command.
        Example: self.cx_profile.dest = ""
      3. gen_cx_profile.interval sets the interval at which the command is run in seconds.
        Example: self.cx_profile.interval = 1
      4. Example Generic profile init:
        class GenTest(LFCliBase):
            def __init__(self, host, port, ssid, security, password, sta_list, name_prefix, upstream,
                         number_template="00000", test_duration="5m", type="lfping", dest="",
                         interval=1, radio="wiphy0",
                super().__init__(host, port, _debug=_debug_on, _halt_on_error=_exit_on_error, _exit_on_fail=_exit_on_fail)
       = host
                self.port = port
                self.ssid = ssid
       = radio
                self.upstream = upstream
                self.sta_list = sta_list
       = security
                self.password = password

                self.number_template = number_template
                self.name_prefix = name_prefix
                self.test_duration = test_duration

                self.local_realm = realm.Realm(, lfclient_port=self.port)
                self.cx_profile = self.local_realm.new_generic_cx_profile()
                self.cx_profile.type = type
                self.cx_profile.dest = dest
                self.cx_profile.interval = interval

            # Station Profile init
  2. Starting Traffic

    1. To start the traffic we can use the gen_cx_profile.start_cx() method. To stop the traffic we can use the gen_cx_profile.stop_cx() method.
    2. Example start and build method:
      def build(self):
          self.station_profile.use_security(, self.ssid, self.password)
          print("Creating stations")
          self.station_profile.set_command_flag("add_sta", "create_admin_down", 1)
          self.station_profile.set_command_param("set_port", "report_timer", 1500)
          self.station_profile.set_command_flag("set_port", "rpt_timer", 1)
          self.station_profile.create(, sta_names_=self.sta_list, debug=self.debug)
          self.cx_profile.create(ports=self.station_profile.station_names, sleep_time=.5)
          self._pass("PASS: Station build finished")
      def start(self, print_pass=False, print_fail=False):
          temp_stas = self.sta_list.copy()
          if self.local_realm.wait_for_ip(temp_stas):
              self._pass("All stations got IPs", print_pass)
              self._fail("Stations failed to get IPs", print_fail)
          cur_time =
          passes = 0
          expected_passes = 0
          end_time = self.local_realm.parse_time("30s") + cur_time
          print("Starting Test...")
          while cur_time < end_time:
              cur_time =
              gen_results = self.json_get("generic/list?fields=name,last+results", debug_=self.debug)
              if gen_results['endpoints'] is not None:
                  for name in gen_results['endpoints']:
                      for k, v in name.items():
                          if v['name'] in self.cx_profile.created_endp and not v['name'].endswith('1'):
                              expected_passes += 1
                              if v['last results'] != "" and "Unreachable" not in v['last results']:
                                  passes += 1
                                  self._fail("%s Failed to ping %s " % (v['name'], self.cx_profile.dest), print_fail)

          if passes == expected_passes:
              self._pass("PASS: All tests passed", print_pass)
  3. Examining The Results

    1. For lfping we can use the last results of the endpoint to determine if the test was successful. An example of this can be seen in our start method. The most common errors for lfping will either be a blank last result or Destination Host Unreachable. Either of these results indicate a failed ping. Successful pings will look like:
      64 bytes from icmp_seq=1 time=4.55 ms *** drop: 0 (0, 0.000)  rx: 1  fail: 0  bytes: 64
      Results can also be seen in the generic tab in the LANForge Manager: Generic Endpoint TabDouble-clicking on an endpoint will allow you to see more specific results as well as the command used by the endpoint. Using the sync button will allow you to see updated results.Generic Endpoint Detailed Info

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