tests: Check if multiple VRF instances can have different ASNs

Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>

tests/topotests/bgp_vrf_different_asn/r1/frr.conf

@@ -0,0 +1,18 @@
+!
+vrf vrf100
+ vni 10100
+exit-vrf
+!
+interface r1-eth0 vrf vrf100
+ ip address 192.168.1.1/24
+!
+router bgp 65000
+ address-family ipv4 unicast
+  import vrf vrf100
+ exit-address-family
+!
+router bgp 65100 vrf vrf100
+ address-family ipv4 unicast
+  redistribute connected
+ exit-address-family
+!

tests/topotests/bgp_vrf_different_asn/test_bgp_vrf_different_asn.py

@@ -0,0 +1,89 @@
+#!/usr/bin/env python
+# SPDX-License-Identifier: ISC
+
+#
+# Copyright (c) 2024 by
+# Donatas Abraitis <donatas@opensourcerouting.org>
+#
+
+import os
+import sys
+import json
+import pytest
+import functools
+
+CWD = os.path.dirname(os.path.realpath(__file__))
+sys.path.append(os.path.join(CWD, "../"))
+
+# pylint: disable=C0413
+from lib import topotest
+from lib.topogen import Topogen, TopoRouter, get_topogen
+
+pytestmark = [pytest.mark.bgpd]
+
+
+def build_topo(tgen):
+    for routern in range(1, 2):
+        tgen.add_router("r{}".format(routern))
+
+    switch = tgen.add_switch("s1")
+    switch.add_link(tgen.gears["r1"])
+
+
+def setup_module(mod):
+    tgen = Topogen(build_topo, mod.__name__)
+    tgen.start_topology()
+
+    r1 = tgen.gears["r1"]
+    r1.run("ip link add vrf100 type vrf table 1001")
+    r1.run("ip link set up dev vrf100")
+    r1.run("ip link set r1-eth0 master vrf100")
+
+    router_list = tgen.routers()
+
+    for _, (rname, router) in enumerate(router_list.items(), 1):
+        router.load_frr_config(os.path.join(CWD, "{}/frr.conf".format(rname)))
+
+    tgen.start_router()
+
+
+def teardown_module(mod):
+    tgen = get_topogen()
+    tgen.stop_topology()
+
+
+def test_bgp_vrf_different_asn():
+    tgen = get_topogen()
+
+    if tgen.routers_have_failure():
+        pytest.skip(tgen.errors)
+
+    def _bgp_check_imported_route():
+        output = json.loads(
+            tgen.gears["r1"].vtysh_cmd("show ip route 192.168.1.0/24 json")
+        )
+        expected = {
+            "192.168.1.0/24": [
+                {
+                    "installed": True,
+                    "selected": True,
+                    "nexthops": [
+                        {
+                            "interfaceName": "vrf100",
+                            "vrf": "vrf100",
+                            "active": True,
+                        }
+                    ],
+                }
+            ]
+        }
+        return topotest.json_cmp(output, expected)
+
+    test_func = functools.partial(_bgp_check_imported_route)
+    _, result = topotest.run_and_expect(test_func, None, count=30, wait=1)
+    assert result is None, "Can't see 192.168.1.0/24 being imported into a default VRF"
+
+
+if __name__ == "__main__":
+    args = ["-s"] + sys.argv[1:]
+    sys.exit(pytest.main(args))