ip-neighbor: Replace feature for the ip-neighbor data-base
[vpp.git] / test / test_neighbor.py
index 9d91f03..cc1357c 100644 (file)
@@ -1,17 +1,25 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import unittest
+import os
 from socket import AF_INET, AF_INET6, inet_pton
 
 from framework import VppTestCase, VppTestRunner
 from vpp_neighbor import VppNeighbor, find_nbr
 from vpp_ip_route import VppIpRoute, VppRoutePath, find_route, \
-    VppIpTable
+    VppIpTable, DpoProto, FibPathType
+from vpp_papi import VppEnum
 
+import scapy.compat
 from scapy.packet import Raw
 from scapy.layers.l2 import Ether, ARP, Dot1Q
 from scapy.layers.inet import IP, UDP
+from scapy.layers.inet6 import IPv6
 from scapy.contrib.mpls import MPLS
+from scapy.layers.inet6 import IPv6
+
+
+NUM_PKTS = 67
 
 # not exported by scapy, so redefined here
 arp_opts = {"who-has": 1, "is-at": 2}
@@ -20,6 +28,14 @@ arp_opts = {"who-has": 1, "is-at": 2}
 class ARPTestCase(VppTestCase):
     """ ARP Test Case """
 
+    @classmethod
+    def setUpClass(cls):
+        super(ARPTestCase, cls).setUpClass()
+
+    @classmethod
+    def tearDownClass(cls):
+        super(ARPTestCase, cls).tearDownClass()
+
     def setUp(self):
         super(ARPTestCase, self).setUp()
 
@@ -140,6 +156,24 @@ class ARPTestCase(VppTestCase):
         #
         self.pg1.generate_remote_hosts(11)
 
+        #
+        # watch for:
+        #  - all neighbour events
+        #  - all neighbor events on pg1
+        #  - neighbor events for host[1] on pg1
+        #
+        self.vapi.want_ip_neighbor_events(enable=1,
+                                          pid=os.getpid())
+        self.vapi.want_ip_neighbor_events(enable=1,
+                                          pid=os.getpid(),
+                                          sw_if_index=self.pg1.sw_if_index)
+        self.vapi.want_ip_neighbor_events(enable=1,
+                                          pid=os.getpid(),
+                                          sw_if_index=self.pg1.sw_if_index,
+                                          ip=self.pg1.remote_hosts[1].ip4)
+
+        self.logger.info(self.vapi.cli("sh ip neighbor-watcher"))
+
         #
         # Send IP traffic to one of these unresolved hosts.
         #  expect the generation of an ARP request
@@ -168,6 +202,14 @@ class ARPTestCase(VppTestCase):
                               self.pg1.remote_hosts[1].mac,
                               self.pg1.remote_hosts[1].ip4)
         dyn_arp.add_vpp_config()
+        self.assertTrue(dyn_arp.query_vpp_config())
+
+        # this matches all of the listnerers
+        es = [self.vapi.wait_for_event(1, "ip_neighbor_event")
+              for i in range(3)]
+        for e in es:
+            self.assertEqual(str(e.neighbor.ip_address),
+                             self.pg1.remote_hosts[1].ip4)
 
         #
         # now we expect IP traffic forwarded
@@ -199,6 +241,11 @@ class ARPTestCase(VppTestCase):
                                  self.pg1.remote_hosts[2].ip4,
                                  is_static=1)
         static_arp.add_vpp_config()
+        es = [self.vapi.wait_for_event(1, "ip_neighbor_event")
+              for i in range(2)]
+        for e in es:
+            self.assertEqual(str(e.neighbor.ip_address),
+                             self.pg1.remote_hosts[2].ip4)
 
         static_p = (Ether(dst=self.pg0.local_mac, src=self.pg0.remote_mac) /
                     IP(src=self.pg0.remote_ip4,
@@ -218,6 +265,19 @@ class ARPTestCase(VppTestCase):
                        self.pg0.remote_ip4,
                        self.pg1._remote_hosts[2].ip4)
 
+        #
+        # remove all the listeners
+        #
+        self.vapi.want_ip_neighbor_events(enable=0,
+                                          pid=os.getpid())
+        self.vapi.want_ip_neighbor_events(enable=0,
+                                          pid=os.getpid(),
+                                          sw_if_index=self.pg1.sw_if_index)
+        self.vapi.want_ip_neighbor_events(enable=0,
+                                          pid=os.getpid(),
+                                          sw_if_index=self.pg1.sw_if_index,
+                                          ip=self.pg1.remote_hosts[1].ip4)
+
         #
         # flap the link. dynamic ARPs get flush, statics don't
         #
@@ -245,6 +305,8 @@ class ARPTestCase(VppTestCase):
                             self.pg1.local_ip4,
                             self.pg1._remote_hosts[1].ip4)
 
+        self.assertFalse(dyn_arp.query_vpp_config())
+        self.assertTrue(static_arp.query_vpp_config())
         #
         # Send an ARP request from one of the so-far unlearned remote hosts
         #
@@ -296,7 +358,16 @@ class ARPTestCase(VppTestCase):
         #
         self.pg2.set_unnumbered(self.pg1.sw_if_index)
 
+        #
+        # test the unnumbered dump both by all interfaces and just the enabled
+        # one
+        #
         unnum = self.vapi.ip_unnumbered_dump()
+        self.assertTrue(len(unnum))
+        self.assertEqual(unnum[0].ip_sw_if_index, self.pg1.sw_if_index)
+        self.assertEqual(unnum[0].sw_if_index, self.pg2.sw_if_index)
+        unnum = self.vapi.ip_unnumbered_dump(self.pg2.sw_if_index)
+        self.assertTrue(len(unnum))
         self.assertEqual(unnum[0].ip_sw_if_index, self.pg1.sw_if_index)
         self.assertEqual(unnum[0].sw_if_index, self.pg2.sw_if_index)
 
@@ -496,7 +567,7 @@ class ARPTestCase(VppTestCase):
                              self.pg1._remote_hosts[9].ip4)
 
         #
-        # Add a hierachy of routes for a host in the sub-net.
+        # Add a hierarchy of routes for a host in the sub-net.
         # Should still get an ARP resp since the cover is attached
         #
         p = (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.pg1.remote_mac) /
@@ -595,8 +666,8 @@ class ARPTestCase(VppTestCase):
         #
         #  2 - don't respond to ARP request from an address not within the
         #      interface's sub-net
-        #   2b - to a prxied address
-        #   2c - not within a differents interface's sub-net
+        #   2b - to a proxied address
+        #   2c - not within a different interface's sub-net
         p = (Ether(dst="ff:ff:ff:ff:ff:ff", src=self.pg0.remote_mac) /
              ARP(op="who-has",
                  hwsrc=self.pg0.remote_mac,
@@ -660,7 +731,6 @@ class ARPTestCase(VppTestCase):
         #
         # cleanup
         #
-        dyn_arp.remove_vpp_config()
         static_arp.remove_vpp_config()
         self.pg2.unset_unnumbered(self.pg1.sw_if_index)
 
@@ -691,8 +761,8 @@ class ARPTestCase(VppTestCase):
         #
         # Configure Proxy ARP for the subnet on PG0addresses on pg0
         #
-        self.vapi.proxy_arp_add_del(self.pg0._local_ip4n_subnet,
-                                    self.pg0._local_ip4n_bcast)
+        self.vapi.proxy_arp_add_del(self.pg0._local_ip4_subnet,
+                                    self.pg0._local_ip4_bcast)
 
         # Make pg2 un-numbered to pg0
         #
@@ -729,8 +799,8 @@ class ARPTestCase(VppTestCase):
         # cleanup
         #
         self.pg2.set_proxy_arp(0)
-        self.vapi.proxy_arp_add_del(self.pg0._local_ip4n_subnet,
-                                    self.pg0._local_ip4n_bcast,
+        self.vapi.proxy_arp_add_del(self.pg0._local_ip4_subnet,
+                                    self.pg0._local_ip4_bcast,
                                     is_add=0)
 
     def test_proxy_arp(self):
@@ -739,7 +809,7 @@ class ARPTestCase(VppTestCase):
         self.pg1.generate_remote_hosts(2)
 
         #
-        # Proxy ARP rewquest packets for each interface
+        # Proxy ARP request packets for each interface
         #
         arp_req_pg0 = (Ether(src=self.pg0.remote_mac,
                              dst="ff:ff:ff:ff:ff:ff") /
@@ -907,7 +977,7 @@ class ARPTestCase(VppTestCase):
         self.pg2.generate_remote_hosts(2)
 
         #
-        # Add a reoute with out going label via an ARP unresolved next-hop
+        # Add a route with out going label via an ARP unresolved next-hop
         #
         ip_10_0_0_1 = VppIpRoute(self, "10.0.0.1", 32,
                                  [VppRoutePath(self.pg2.remote_hosts[1].ip4,
@@ -922,7 +992,7 @@ class ARPTestCase(VppTestCase):
                    dst=self.pg0.local_mac) /
              IP(src=self.pg0.remote_ip4, dst="10.0.0.1") /
              UDP(sport=1234, dport=1234) /
-             Raw('\xa5' * 100))
+             Raw(b'\xa5' * 100))
 
         self.pg0.add_stream(p)
         self.pg_enable_capture(self.pg_interfaces)
@@ -969,11 +1039,7 @@ class ARPTestCase(VppTestCase):
               UDP(sport=1234, dport=1234) /
               Raw())
 
-        self.pg0.add_stream(p0)
-        self.pg_enable_capture(self.pg_interfaces)
-        self.pg_start()
-
-        rx1 = self.pg1.get_capture(1)
+        rx1 = self.send_and_expect(self.pg0, [p0], self.pg1)
 
         self.verify_arp_req(rx1[0],
                             self.pg1.local_mac,
@@ -990,20 +1056,14 @@ class ARPTestCase(VppTestCase):
                   hwsrc="00:00:5e:00:01:09", pdst=self.pg1.local_ip4,
                   psrc=self.pg1.remote_ip4))
 
-        self.pg1.add_stream(p1)
-        self.pg_enable_capture(self.pg_interfaces)
-        self.pg_start()
+        self.send_and_assert_no_replies(self.pg1, p1, "ARP reply")
 
         #
         # IP packet destined for pg1 remote host arrives on pg0 again.
         # VPP should have an ARP entry for that address now and the packet
         # should be sent out pg1.
         #
-        self.pg0.add_stream(p0)
-        self.pg_enable_capture(self.pg_interfaces)
-        self.pg_start()
-
-        rx1 = self.pg1.get_capture(1)
+        rx1 = self.send_and_expect(self.pg0, [p0], self.pg1)
 
         self.verify_ip(rx1[0],
                        self.pg1.local_mac,
@@ -1060,7 +1120,7 @@ class ARPTestCase(VppTestCase):
 
         #
         # remove the duplicate on pg1
-        # packet stream shoud generate ARPs out of pg1
+        # packet stream should generate ARPs out of pg1
         #
         arp_pg1.remove_vpp_config()
 
@@ -1146,6 +1206,7 @@ class ARPTestCase(VppTestCase):
         # clean-up
         #
         self.pg2.unconfig_ip4()
+        static_arp.remove_vpp_config()
         self.pg2.set_table_ip4(0)
 
     def test_arp_incomplete(self):
@@ -1185,8 +1246,9 @@ class ARPTestCase(VppTestCase):
         #
         # change the interface's MAC
         #
-        mac = [chr(0x00), chr(0x00), chr(0x00),
-               chr(0x33), chr(0x33), chr(0x33)]
+        mac = [scapy.compat.chb(0x00), scapy.compat.chb(0x00),
+               scapy.compat.chb(0x00), scapy.compat.chb(0x33),
+               scapy.compat.chb(0x33), scapy.compat.chb(0x33)]
         mac_string = ''.join(mac)
 
         self.vapi.sw_interface_set_mac_address(self.pg1.sw_if_index,
@@ -1212,7 +1274,7 @@ class ARPTestCase(VppTestCase):
                        self.pg1.remote_hosts[1].ip4)
 
         #
-        # set the mac address on the inteface that does not have a
+        # set the mac address on the interface that does not have a
         # configured subnet and thus no glean
         #
         self.vapi.sw_interface_set_mac_address(self.pg2.sw_if_index,
@@ -1281,7 +1343,7 @@ class ARPTestCase(VppTestCase):
                                  mac=self.pg1.remote_hosts[3].mac))
 
         #
-        # GARPs (requets nor replies) for host we don't know yet
+        # GARPs (request nor replies) for host we don't know yet
         # don't result in new neighbour entries
         #
         p1 = (Ether(dst="ff:ff:ff:ff:ff:ff",
@@ -1316,6 +1378,593 @@ class ARPTestCase(VppTestCase):
                                   self.pg1.sw_if_index,
                                   self.pg1.remote_hosts[2].ip4))
 
+    def test_arp_incomplete(self):
+        """ Incomplete Entries """
+
+        #
+        # ensure that we throttle the ARP and ND requests
+        #
+        self.pg0.generate_remote_hosts(2)
+
+        #
+        # IPv4/ARP
+        #
+        ip_10_0_0_1 = VppIpRoute(self, "10.0.0.1", 32,
+                                 [VppRoutePath(self.pg0.remote_hosts[1].ip4,
+                                               self.pg0.sw_if_index)])
+        ip_10_0_0_1.add_vpp_config()
+
+        p1 = (Ether(dst=self.pg1.local_mac,
+                    src=self.pg1.remote_mac) /
+              IP(src=self.pg1.remote_ip4,
+                 dst="10.0.0.1") /
+              UDP(sport=1234, dport=1234) /
+              Raw())
+
+        self.pg1.add_stream(p1 * 257)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg0._get_capture(1)
+
+        #
+        # how many we get is going to be dependent on the time for packet
+        # processing but it should be small
+        #
+        self.assertLess(len(rx), 64)
+
+        #
+        # IPv6/ND
+        #
+        ip_10_1 = VppIpRoute(self, "10::1", 128,
+                             [VppRoutePath(self.pg0.remote_hosts[1].ip6,
+                                           self.pg0.sw_if_index,
+                                           proto=DpoProto.DPO_PROTO_IP6)])
+        ip_10_1.add_vpp_config()
+
+        p1 = (Ether(dst=self.pg1.local_mac,
+                    src=self.pg1.remote_mac) /
+              IPv6(src=self.pg1.remote_ip6,
+                   dst="10::1") /
+              UDP(sport=1234, dport=1234) /
+              Raw())
+
+        self.pg1.add_stream(p1 * 257)
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        rx = self.pg0._get_capture(1)
+
+        #
+        # how many we get is going to be dependent on the time for packet
+        # processing but it should be small
+        #
+        self.assertLess(len(rx), 64)
+
+    def test_arp_forus(self):
+        """ ARP for for-us """
+
+        #
+        # Test that VPP responds with ARP requests to addresses that
+        # are connected and local routes.
+        # Use one of the 'remote' addresses in the subnet as a local address
+        # The intention of this route is that it then acts like a secondary
+        # address added to an interface
+        #
+        self.pg0.generate_remote_hosts(2)
+
+        forus = VppIpRoute(
+            self, self.pg0.remote_hosts[1].ip4, 32,
+            [VppRoutePath("0.0.0.0",
+                          self.pg0.sw_if_index,
+                          type=FibPathType.FIB_PATH_TYPE_LOCAL)])
+        forus.add_vpp_config()
+
+        p = (Ether(dst="ff:ff:ff:ff:ff:ff",
+                   src=self.pg0.remote_mac) /
+             ARP(op="who-has",
+                 hwdst=self.pg0.local_mac,
+                 hwsrc=self.pg0.remote_mac,
+                 pdst=self.pg0.remote_hosts[1].ip4,
+                 psrc=self.pg0.remote_ip4))
+
+        rx = self.send_and_expect(self.pg0, [p], self.pg0)
+
+        self.verify_arp_resp(rx[0],
+                             self.pg0.local_mac,
+                             self.pg0.remote_mac,
+                             self.pg0.remote_hosts[1].ip4,
+                             self.pg0.remote_ip4)
+
+    def test_arp_table_swap(self):
+        #
+        # Generate some hosts on the LAN
+        #
+        N_NBRS = 4
+        self.pg1.generate_remote_hosts(N_NBRS)
+
+        for n in range(N_NBRS):
+            # a route thru each neighbour
+            VppIpRoute(self, "10.0.0.%d" % n, 32,
+                       [VppRoutePath(self.pg1.remote_hosts[n].ip4,
+                                     self.pg1.sw_if_index)]).add_vpp_config()
+
+            # resolve each neighbour
+            p1 = (Ether(dst=self.pg1.local_mac, src=self.pg1.remote_mac) /
+                  ARP(op="is-at", hwdst=self.pg1.local_mac,
+                      hwsrc="00:00:5e:00:01:09", pdst=self.pg1.local_ip4,
+                      psrc=self.pg1.remote_hosts[n].ip4))
+
+            self.send_and_assert_no_replies(self.pg1, p1, "ARP reply")
+
+        self.logger.info(self.vapi.cli("sh ip neighbors"))
+
+        #
+        # swap the table pg1 is in
+        #
+        table = VppIpTable(self, 100).add_vpp_config()
+
+        self.pg1.unconfig_ip4()
+        self.pg1.set_table_ip4(100)
+        self.pg1.config_ip4()
+
+        #
+        # all neighbours are cleared
+        #
+        for n in range(N_NBRS):
+            self.assertFalse(find_nbr(self,
+                                      self.pg1.sw_if_index,
+                                      self.pg1.remote_hosts[n].ip4))
+
+        #
+        # packets to all neighbours generate ARP requests
+        #
+        for n in range(N_NBRS):
+            # a route thru each neighbour
+            VppIpRoute(self, "10.0.0.%d" % n, 32,
+                       [VppRoutePath(self.pg1.remote_hosts[n].ip4,
+                                     self.pg1.sw_if_index)],
+                       table_id=100).add_vpp_config()
+
+            p = (Ether(src=self.pg1.remote_hosts[n].mac,
+                       dst=self.pg1.local_mac) /
+                 IP(src=self.pg1.remote_hosts[n].ip4,
+                    dst="10.0.0.%d" % n) /
+                 Raw(b'0x5' * 100))
+            rxs = self.send_and_expect(self.pg1, [p], self.pg1)
+            for rx in rxs:
+                self.verify_arp_req(rx,
+                                    self.pg1.local_mac,
+                                    self.pg1.local_ip4,
+                                    self.pg1.remote_hosts[n].ip4)
+
+        self.pg1.unconfig_ip4()
+        self.pg1.set_table_ip4(0)
+
+
+class NeighborStatsTestCase(VppTestCase):
+    """ ARP/ND Counters """
+
+    @classmethod
+    def setUpClass(cls):
+        super(NeighborStatsTestCase, cls).setUpClass()
+
+    @classmethod
+    def tearDownClass(cls):
+        super(NeighborStatsTestCase, cls).tearDownClass()
+
+    def setUp(self):
+        super(NeighborStatsTestCase, self).setUp()
+
+        self.create_pg_interfaces(range(2))
+
+        # pg0 configured with ip4 and 6 addresses used for input
+        # pg1 configured with ip4 and 6 addresses used for output
+        # pg2 is unnumbered to pg0
+        for i in self.pg_interfaces:
+            i.admin_up()
+            i.config_ip4()
+            i.config_ip6()
+            i.resolve_arp()
+            i.resolve_ndp()
+
+    def tearDown(self):
+        super(NeighborStatsTestCase, self).tearDown()
+
+        for i in self.pg_interfaces:
+            i.unconfig_ip4()
+            i.unconfig_ip6()
+            i.admin_down()
+
+    def test_arp_stats(self):
+        """ ARP Counters """
+
+        self.vapi.cli("adj counters enable")
+        self.pg1.generate_remote_hosts(2)
+
+        arp1 = VppNeighbor(self,
+                           self.pg1.sw_if_index,
+                           self.pg1.remote_hosts[0].mac,
+                           self.pg1.remote_hosts[0].ip4)
+        arp1.add_vpp_config()
+        arp2 = VppNeighbor(self,
+                           self.pg1.sw_if_index,
+                           self.pg1.remote_hosts[1].mac,
+                           self.pg1.remote_hosts[1].ip4)
+        arp2.add_vpp_config()
+
+        p1 = (Ether(dst=self.pg0.local_mac,
+                    src=self.pg0.remote_mac) /
+              IP(src=self.pg0.remote_ip4,
+                 dst=self.pg1.remote_hosts[0].ip4) /
+              UDP(sport=1234, dport=1234) /
+              Raw())
+        p2 = (Ether(dst=self.pg0.local_mac,
+                    src=self.pg0.remote_mac) /
+              IP(src=self.pg0.remote_ip4,
+                 dst=self.pg1.remote_hosts[1].ip4) /
+              UDP(sport=1234, dport=1234) /
+              Raw())
+
+        rx = self.send_and_expect(self.pg0, p1 * NUM_PKTS, self.pg1)
+        rx = self.send_and_expect(self.pg0, p2 * NUM_PKTS, self.pg1)
+
+        self.assertEqual(NUM_PKTS, arp1.get_stats()['packets'])
+        self.assertEqual(NUM_PKTS, arp2.get_stats()['packets'])
+
+        rx = self.send_and_expect(self.pg0, p1 * NUM_PKTS, self.pg1)
+        self.assertEqual(NUM_PKTS*2, arp1.get_stats()['packets'])
+
+    def test_nd_stats(self):
+        """ ND Counters """
+
+        self.vapi.cli("adj counters enable")
+        self.pg0.generate_remote_hosts(3)
+
+        nd1 = VppNeighbor(self,
+                          self.pg0.sw_if_index,
+                          self.pg0.remote_hosts[1].mac,
+                          self.pg0.remote_hosts[1].ip6)
+        nd1.add_vpp_config()
+        nd2 = VppNeighbor(self,
+                          self.pg0.sw_if_index,
+                          self.pg0.remote_hosts[2].mac,
+                          self.pg0.remote_hosts[2].ip6)
+        nd2.add_vpp_config()
+
+        p1 = (Ether(dst=self.pg1.local_mac,
+                    src=self.pg1.remote_mac) /
+              IPv6(src=self.pg1.remote_ip6,
+                   dst=self.pg0.remote_hosts[1].ip6) /
+              UDP(sport=1234, dport=1234) /
+              Raw())
+        p2 = (Ether(dst=self.pg1.local_mac,
+                    src=self.pg1.remote_mac) /
+              IPv6(src=self.pg1.remote_ip6,
+                   dst=self.pg0.remote_hosts[2].ip6) /
+              UDP(sport=1234, dport=1234) /
+              Raw())
+
+        rx = self.send_and_expect(self.pg1, p1 * 16, self.pg0)
+        rx = self.send_and_expect(self.pg1, p2 * 16, self.pg0)
+
+        self.assertEqual(16, nd1.get_stats()['packets'])
+        self.assertEqual(16, nd2.get_stats()['packets'])
+
+        rx = self.send_and_expect(self.pg1, p1 * NUM_PKTS, self.pg0)
+        self.assertEqual(NUM_PKTS+16, nd1.get_stats()['packets'])
+
+
+class NeighborAgeTestCase(VppTestCase):
+    """ ARP/ND Aging """
+
+    @classmethod
+    def setUpClass(cls):
+        super(NeighborAgeTestCase, cls).setUpClass()
+
+    @classmethod
+    def tearDownClass(cls):
+        super(NeighborAgeTestCase, cls).tearDownClass()
+
+    def setUp(self):
+        super(NeighborAgeTestCase, self).setUp()
+
+        self.create_pg_interfaces(range(1))
+
+        # pg0 configured with ip4 and 6 addresses used for input
+        # pg1 configured with ip4 and 6 addresses used for output
+        # pg2 is unnumbered to pg0
+        for i in self.pg_interfaces:
+            i.admin_up()
+            i.config_ip4()
+            i.config_ip6()
+            i.resolve_arp()
+            i.resolve_ndp()
+
+    def tearDown(self):
+        super(NeighborAgeTestCase, self).tearDown()
+
+        for i in self.pg_interfaces:
+            i.unconfig_ip4()
+            i.unconfig_ip6()
+            i.admin_down()
+
+    def wait_for_no_nbr(self, intf, address,
+                        n_tries=50, s_time=1):
+        while (n_tries):
+            if not find_nbr(self, intf, address):
+                return True
+            n_tries = n_tries - 1
+            self.sleep(s_time)
+
+        return False
+
+    def verify_arp_req(self, rx, smac, sip, dip):
+        ether = rx[Ether]
+        self.assertEqual(ether.dst, "ff:ff:ff:ff:ff:ff")
+        self.assertEqual(ether.src, smac)
+
+        arp = rx[ARP]
+        self.assertEqual(arp.hwtype, 1)
+        self.assertEqual(arp.ptype, 0x800)
+        self.assertEqual(arp.hwlen, 6)
+        self.assertEqual(arp.plen, 4)
+        self.assertEqual(arp.op, arp_opts["who-has"])
+        self.assertEqual(arp.hwsrc, smac)
+        self.assertEqual(arp.hwdst, "00:00:00:00:00:00")
+        self.assertEqual(arp.psrc, sip)
+        self.assertEqual(arp.pdst, dip)
+
+    def test_age(self):
+        """ Aging/Recycle """
+
+        self.vapi.cli("set logging unthrottle 0")
+        self.vapi.cli("set logging size %d" % 0xffff)
+
+        self.pg0.generate_remote_hosts(201)
+
+        vaf = VppEnum.vl_api_address_family_t
+
+        #
+        # start listening on all interfaces
+        #
+        self.pg_enable_capture(self.pg_interfaces)
+
+        #
+        # Set the neighbor configuration:
+        #   limi = 200
+        #   age  = 0 seconds
+        #   recycle = false
+        #
+        self.vapi.ip_neighbor_config(af=vaf.ADDRESS_IP4,
+                                     max_number=200,
+                                     max_age=0,
+                                     recycle=False)
+
+        self.vapi.cli("sh ip neighbor-config")
+
+        # add the 198 neighbours that should pass (-1 for one created in setup)
+        for ii in range(200):
+            VppNeighbor(self,
+                        self.pg0.sw_if_index,
+                        self.pg0.remote_hosts[ii].mac,
+                        self.pg0.remote_hosts[ii].ip4).add_vpp_config()
+
+        # one more neighbor over the limit should fail
+        with self.vapi.assert_negative_api_retval():
+            VppNeighbor(self,
+                        self.pg0.sw_if_index,
+                        self.pg0.remote_hosts[200].mac,
+                        self.pg0.remote_hosts[200].ip4).add_vpp_config()
+
+        #
+        # change the config to allow recycling the old neighbors
+        #
+        self.vapi.ip_neighbor_config(af=vaf.ADDRESS_IP4,
+                                     max_number=200,
+                                     max_age=0,
+                                     recycle=True)
+
+        # now new additions are allowed
+        VppNeighbor(self,
+                    self.pg0.sw_if_index,
+                    self.pg0.remote_hosts[200].mac,
+                    self.pg0.remote_hosts[200].ip4).add_vpp_config()
+
+        # add the first neighbor we configured has been re-used
+        self.assertFalse(find_nbr(self,
+                                  self.pg0.sw_if_index,
+                                  self.pg0.remote_hosts[0].ip4))
+        self.assertTrue(find_nbr(self,
+                                 self.pg0.sw_if_index,
+                                 self.pg0.remote_hosts[200].ip4))
+
+        #
+        # change the config to age old neighbors
+        #
+        self.vapi.ip_neighbor_config(af=vaf.ADDRESS_IP4,
+                                     max_number=200,
+                                     max_age=2,
+                                     recycle=True)
+
+        self.vapi.cli("sh ip4 neighbor-sorted")
+
+        #
+        # expect probes from all these ARP entries as they age
+        # 3 probes for each neighbor 3*200 = 600
+        rxs = self.pg0.get_capture(600, timeout=8)
+
+        for ii in range(3):
+            for jj in range(200):
+                rx = rxs[ii*200 + jj]
+                # rx.show()
+
+        #
+        # 3 probes sent then 1 more second to see if a reply comes, before
+        # they age out
+        #
+        for jj in range(1, 201):
+            self.wait_for_no_nbr(self.pg0.sw_if_index,
+                                 self.pg0.remote_hosts[jj].ip4)
+
+        self.assertFalse(self.vapi.ip_neighbor_dump(sw_if_index=0xffffffff,
+                                                    af=vaf.ADDRESS_IP4))
+
+        #
+        # load up some neighbours again with 2s aging enabled
+        # they should be removed after 10s (2s age + 4s for probes + gap)
+        #
+        for ii in range(10):
+            VppNeighbor(self,
+                        self.pg0.sw_if_index,
+                        self.pg0.remote_hosts[ii].mac,
+                        self.pg0.remote_hosts[ii].ip4).add_vpp_config()
+        self.sleep(10)
+        self.assertFalse(self.vapi.ip_neighbor_dump(sw_if_index=0xffffffff,
+                                                    af=vaf.ADDRESS_IP4))
+
+        #
+        # check if we can set age and recycle with empty neighbor list
+        #
+        self.vapi.ip_neighbor_config(af=vaf.ADDRESS_IP4,
+                                     max_number=200,
+                                     max_age=1000,
+                                     recycle=True)
+
+        #
+        # load up some neighbours again, then disable the aging
+        # they should still be there in 10 seconds time
+        #
+        for ii in range(10):
+            VppNeighbor(self,
+                        self.pg0.sw_if_index,
+                        self.pg0.remote_hosts[ii].mac,
+                        self.pg0.remote_hosts[ii].ip4).add_vpp_config()
+        self.vapi.ip_neighbor_config(af=vaf.ADDRESS_IP4,
+                                     max_number=200,
+                                     max_age=0,
+                                     recycle=False)
+
+        self.sleep(10)
+        self.assertTrue(find_nbr(self,
+                                 self.pg0.sw_if_index,
+                                 self.pg0.remote_hosts[0].ip4))
+
+
+class NeighborReplaceTestCase(VppTestCase):
+    """ ARP/ND Replacement """
+
+    @classmethod
+    def setUpClass(cls):
+        super(NeighborReplaceTestCase, cls).setUpClass()
+
+    @classmethod
+    def tearDownClass(cls):
+        super(NeighborReplaceTestCase, cls).tearDownClass()
+
+    def setUp(self):
+        super(NeighborReplaceTestCase, self).setUp()
+
+        self.create_pg_interfaces(range(4))
+
+        # pg0 configured with ip4 and 6 addresses used for input
+        # pg1 configured with ip4 and 6 addresses used for output
+        # pg2 is unnumbered to pg0
+        for i in self.pg_interfaces:
+            i.admin_up()
+            i.config_ip4()
+            i.config_ip6()
+            i.resolve_arp()
+            i.resolve_ndp()
+
+    def tearDown(self):
+        super(NeighborReplaceTestCase, self).tearDown()
+
+        for i in self.pg_interfaces:
+            i.unconfig_ip4()
+            i.unconfig_ip6()
+            i.admin_down()
+
+    def test_replace(self):
+        """ replace """
+
+        N_HOSTS = 16
+
+        for i in self.pg_interfaces:
+            i.generate_remote_hosts(N_HOSTS)
+            i.configure_ipv4_neighbors()
+            i.configure_ipv6_neighbors()
+
+        # replace them all
+        self.vapi.ip_neighbor_replace_begin()
+        self.vapi.ip_neighbor_replace_end()
+
+        for i in self.pg_interfaces:
+            for h in range(N_HOSTS):
+                self.assertFalse(find_nbr(self,
+                                          self.pg0.sw_if_index,
+                                          self.pg0.remote_hosts[h].ip4))
+                self.assertFalse(find_nbr(self,
+                                          self.pg0.sw_if_index,
+                                          self.pg0.remote_hosts[h].ip6))
+
+        #
+        # and them all back via the API
+        #
+        for i in self.pg_interfaces:
+            for h in range(N_HOSTS):
+                VppNeighbor(self,
+                            i.sw_if_index,
+                            i.remote_hosts[h].mac,
+                            i.remote_hosts[h].ip4).add_vpp_config()
+                VppNeighbor(self,
+                            i.sw_if_index,
+                            i.remote_hosts[h].mac,
+                            i.remote_hosts[h].ip6).add_vpp_config()
+
+        #
+        # begin the replacement again, this time touch some
+        # the neighbours on pg1 so they are not deleted
+        #
+        self.vapi.ip_neighbor_replace_begin()
+
+        # update from the API all neighbours on pg1
+        for h in range(N_HOSTS):
+            VppNeighbor(self,
+                        self.pg1.sw_if_index,
+                        self.pg1.remote_hosts[h].mac,
+                        self.pg1.remote_hosts[h].ip4).add_vpp_config()
+            VppNeighbor(self,
+                        self.pg1.sw_if_index,
+                        self.pg1.remote_hosts[h].mac,
+                        self.pg1.remote_hosts[h].ip6).add_vpp_config()
+
+        # update from the data-plane all neighbours on pg3
+        self.pg3.configure_ipv4_neighbors()
+        self.pg3.configure_ipv6_neighbors()
+
+        # complete the replacement
+        self.logger.info(self.vapi.cli("sh ip neighbors"))
+        self.vapi.ip_neighbor_replace_end()
+
+        for i in self.pg_interfaces:
+            if i == self.pg1 or i == self.pg3:
+                # neighbours on pg1 and pg3 are still present
+                for h in range(N_HOSTS):
+                    self.assertTrue(find_nbr(self,
+                                             i.sw_if_index,
+                                             i.remote_hosts[h].ip4))
+                    self.assertTrue(find_nbr(self,
+                                             i.sw_if_index,
+                                             i.remote_hosts[h].ip6))
+            else:
+                # all other neighbours are toast
+                for h in range(N_HOSTS):
+                    self.assertFalse(find_nbr(self,
+                                              i.sw_if_index,
+                                              i.remote_hosts[h].ip4))
+                    self.assertFalse(find_nbr(self,
+                                              i.sw_if_index,
+                                              i.remote_hosts[h].ip6))
+
 
 if __name__ == '__main__':
     unittest.main(testRunner=VppTestRunner)