def METHOD_NAME():
    tgen = get_topogen()
    if tgen.routers_have_failure():
        pytest.skip(tgen.errors)
    router1 = tgen.gears["r1"]
    router2 = tgen.gears["r2"]
    # format (router to configure, command, expected received prefixes on r2)
    tests = [
        # test of the initial config
        (None, 2),
        # modifying the max-prefix-out value
        (
            "router bgp\n address-family ipv4\n neighbor 192.168.255.1 maximum-prefix-out 4",
            4,
        ),
        # removing the max-prefix-out value
        (
            "router bgp\n address-family ipv4\n no neighbor 192.168.255.1 maximum-prefix-out",
            6,
        ),
        # setting a max-prefix-out value
        (
            "router bgp\n address-family ipv4\n neighbor 192.168.255.1 maximum-prefix-out 3",
            3,
        ),
        # setting a max-prefix-out value - higher than the total number of prefix
        (
            "router bgp\n address-family ipv4\n neighbor 192.168.255.1 maximum-prefix-out 8",
            6,
        ),
        # adding a new prefix
        ("router bgp\n int lo\n ip address 172.16.255.249/32", 7),
        # setting a max-prefix-out value - lower than the total number of prefix
        (
            "router bgp\n address-family ipv4\n neighbor 192.168.255.1 maximum-prefix-out 1",
            1,
        ),
        # adding a new prefix
        ("router bgp\n int lo\n ip address 172.16.255.248/32", 1),
        # removing the max-prefix-out value
        (
            "router bgp\n address-family ipv4\n no neighbor 192.168.255.1 maximum-prefix-out 1",
            8,
        ),
        # test setting the existing neighbor into a peer-group with a max-prefix-out value
        (
            """
                router bgp
                 neighbor test peer-group
                 neighbor test remote-as 65002
                 neighbor test timers 3 10
                 address-family ipv4
                  neighbor test maximum-prefix-out 3
                 !
                 neighbor 192.168.255.1 peer-group test
            """,
            3,
        ),
        # max-prefix-out value of the neighbor must take the precedence
        (
            "router bgp\n address-family ipv4\n neighbor 192.168.255.1 maximum-prefix-out 4",
            4,
        ),
        (
            "router bgp\n address-family ipv4\n no neighbor 192.168.255.1 maximum-prefix-out",
            3,
        ),
        (
            """
                router bgp
                 no neighbor 192.168.255.1 peer-group test
                 neighbor 192.168.255.1 remote-as 65002
                 neighbor 192.168.255.1 timers 3 10
            """,
            8,
        ),
        (
            "router bgp\n address-family ipv4\n neighbor 192.168.255.1 maximum-prefix-out 5",
            5,
        ),
        # test setting the existing neighbor with a max-pref-out value into a peer-group with a max-pref-out value
        ("router bgp\n neighbor 192.168.255.1 peer-group test", 5),
        (
            "router bgp\n address-family ipv4\n no neighbor 192.168.255.1 maximum-prefix-out 5",
            3,
        ),
    ]
    def _bgp_converge(router, nb_prefixes):
        output = json.loads(router.vtysh_cmd("show ip bgp neighbor 192.168.255.2 json"))
        expected = {
            "192.168.255.2": {
                "bgpState": "Established",
                "addressFamilyInfo": {
                    "ipv4Unicast": {"acceptedPrefixCounter": nb_prefixes}
                },
            }
        }
        return topotest.json_cmp(output, expected)
    for test in tests:
        cfg, exp_prfxs = test
        if cfg:
            cmd = (
                """
              configure terminal
               %s
            """
                % cfg
            )
            router1.vtysh_cmd(cmd)
        test_func = functools.partial(_bgp_converge, router2, exp_prfxs)
        success, result = topotest.run_and_expect(test_func, None, count=30, wait=0.5)
        assert result is None, 'Failed bgp convergence in "{}"'.format(router2)