tests/topotests/bgp_max_med_on_startup/test_bgp_max_med_on_startup.py

   1 #!/usr/bin/env python
   2
   3 #
   4 # test_bgp_max_med_on_startup.py
   5 #
   6 # Copyright (c) 2022 Rubicon Communications, LLC.
   7 #
   8 # Permission to use, copy, modify, and/or distribute this software
   9 # for any purpose with or without fee is hereby granted, provided
  10 # that the above copyright notice and this permission notice appear
  11 # in all copies.
  12 #
  13 # THE SOFTWARE IS PROVIDED "AS IS" AND NETDEF DISCLAIMS ALL WARRANTIES
  14 # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  15 # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NETDEF BE LIABLE FOR
  16 # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY
  17 # DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
  18 # WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  19 # ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  20 # OF THIS SOFTWARE.
  21 #
  22
  23 """
  24 Test whether `bgp max-med on-startup (5-86400) [(0-4294967295)]` is working
  25 correctly.
  26 """
  27
  28 import os
  29 import sys
  30 import json
  31 import pytest
  32 import functools
  33
  34 CWD = os.path.dirname(os.path.realpath(__file__))
  35 sys.path.append(os.path.join(CWD, "../"))
  36
  37 # pylint: disable=C0413
  38 from lib import topotest
  39 from lib.topogen import Topogen, TopoRouter, get_topogen
  40
  41 pytestmark = [pytest.mark.bgpd]
  42
  43
  44 def build_topo(tgen):
  45     for routern in range(1, 3):
  46         tgen.add_router("r{}".format(routern))
  47
  48     switch = tgen.add_switch("s1")
  49     switch.add_link(tgen.gears["r1"])
  50     switch.add_link(tgen.gears["r2"])
  51
  52
  53 def setup_module(mod):
  54     tgen = Topogen(build_topo, mod.__name__)
  55     tgen.start_topology()
  56
  57     router_list = tgen.routers()
  58
  59     for i, (rname, router) in enumerate(router_list.items(), 1):
  60         router.load_config(
  61             TopoRouter.RD_ZEBRA, os.path.join(CWD, "{}/zebra.conf".format(rname))
  62         )
  63         router.load_config(
  64             TopoRouter.RD_BGP, os.path.join(CWD, "{}/bgpd.conf".format(rname))
  65         )
  66
  67     tgen.start_router()
  68
  69
  70 def teardown_module(mod):
  71     tgen = get_topogen()
  72     tgen.stop_topology()
  73
  74
  75 def test_bgp_max_med_on_startup():
  76     tgen = get_topogen()
  77
  78     if tgen.routers_have_failure():
  79         pytest.skip(tgen.errors)
  80
  81     router1 = tgen.gears["r1"]
  82     router2 = tgen.gears["r2"]
  83
  84     def _bgp_converge(router):
  85         output = json.loads(router.vtysh_cmd("show ip bgp neighbor 192.168.255.1 json"))
  86         expected = {"192.168.255.1": {"bgpState": "Established"}}
  87         return topotest.json_cmp(output, expected)
  88
  89     def _bgp_has_routes(router, metric):
  90         output = json.loads(
  91             router.vtysh_cmd("show ip bgp neighbor 192.168.255.1 routes json")
  92         )
  93         expected = {"routes": {"172.16.255.254/32": [{"metric": metric}]}}
  94         return topotest.json_cmp(output, expected)
  95
  96     # Check session is established
  97     test_func = functools.partial(_bgp_converge, router2)
  98     success, result = topotest.run_and_expect(test_func, None, count=30, wait=0.5)
  99     assert result is None, "Failed bgp convergence on r2"
 100
 101     # Check metric has value of max-med
 102     test_func = functools.partial(_bgp_has_routes, router2, 777)
 103     success, result = topotest.run_and_expect(test_func, None, count=30, wait=0.5)
 104     assert result is None, "r2 does not receive routes with metric 777"
 105
 106     # Check that when the max-med timer expires, metric is updated
 107     test_func = functools.partial(_bgp_has_routes, router2, 0)
 108     success, result = topotest.run_and_expect(test_func, None, count=16, wait=0.5)
 109     assert result is None, "r2 does not receive routes with metric 0"
 110
 111
 112 if __name__ == "__main__":
 113     args = ["-s"] + sys.argv[1:]
 114     sys.exit(pytest.main(args))