os-morphing: fix static ip configuration if the mac changes

coriolis/osmorphing/base.py

@@ -1008,6 +1008,9 @@ def _setup_network_preservation(self, nics_info) -> None:
 
         for nic in nics_info:
             nic_mac = nic.get('mac_address')
+            new_nic_mac = nic.get('new_mac_address') or nic_mac
+            if new_nic_mac != nic_mac:
+                LOG.info("MAC address changed: %s -> %s", nic_mac, new_nic_mac)
             nic_ips = nic.get('ip_addresses')
             if not nic_mac:
                 LOG.warning(
@@ -1020,22 +1023,37 @@ def _setup_network_preservation(self, nics_info) -> None:
                 mac_address = info.get('mac_address')
                 ip_addresses = info.get('ip_addresses', [])
                 if mac_address and mac_address == nic_mac:
+                    if new_nic_mac != nic_mac:
+                        raise exception.CoriolisException(
+                            "The NIC '%s' configuration explicitly targets "
+                            "MAC '%s', however its MAC changed to '%s'. "
+                            "Coriolis defines udev rules for preserving the "
+                            "interface name, mapping it to the new MAC "
+                            "address but DOES NOT modify Linux network "
+                            "configuration files. Depending on the target "
+                            "platform capabilities, consider using DHCP, "
+                            "enabling MAC address preservation or removing "
+                            "the explicit MAC filter from the NIC "
+                            "configuration."
+                            % (nic.get('name'), nic_mac, new_nic_mac))
                     LOG.info(
-                        "Found matching interface for NIC '%s' with MAC '%s'",
+                        "Found matching interface for NIC '%s' with MAC '%s'.",
                         nic.get('name'), nic_mac)
                     matching_ifaces[iface] = nic_mac
                     break
                 if ip_addresses and nic_ips:
                     if set(ip_addresses) & set(nic_ips):
                         LOG.info(
-                            "Found matching interface for NIC '%s' with MAC "
-                            "'%s'", nic.get('name'), nic_mac)
-                        matching_ifaces[iface] = nic_mac
+                            "Found matching interface for NIC '%s' "
+                            "with new MAC '%s', identified by IP.",
+                            nic.get('name'), new_nic_mac)
+                        matching_ifaces[iface] = new_nic_mac
                         break
             if not matching_ifaces:
                 LOG.warning(
                     "Could not find a matching guest interface for NIC '%s' "
-                    "with MAC address '%s'", nic, nic_mac)
+                    "with MAC address '%s' (old MAC address: %s)",
+                    nic, new_nic_mac, nic_mac)
             net_ifaces_info.update(matching_ifaces)
 
         self._add_net_udev_rules(net_ifaces_info)

coriolis/osmorphing/windows.py

@@ -708,8 +708,20 @@ def _get_static_nics_info(self, nics_info, ips_info):
     def _write_static_ip_script(self, base_dir, nics_info, ips_info):
         scripts_dir = self._get_cbslinit_scripts_dir(base_dir)
         script_path = "%s\\01-static-ip-config.ps1" % scripts_dir
+
+        nics_info = copy.deepcopy(nics_info)
+        for nic in nics_info:
+            # The static ip configuration script only requires the new
+            # MAC address.
+            if nic.get("new_mac_address"):
+                LOG.info(
+                    "Updated mac address: %s -> %s",
+                    nic["mac_address"], nic["new_mac_address"])
+                nic["mac_address"] = nic["new_mac_address"]
+
         nics_info_dump = json.dumps(nics_info)
         ips_info_dump = json.dumps(ips_info)
+
         contents = STATIC_IP_SCRIPT_TEMPLATE % {
             'nics_info': base64.b64encode(nics_info_dump.encode()).decode(),
             'ips_info': base64.b64encode(ips_info_dump.encode()).decode()}

coriolis/tests/osmorphing/test_base.py

@@ -1894,6 +1894,38 @@ def test__add_net_udev_rules(self, mock_write_file_sudo, mock_test_path):
                 "eth2": "FF:FF:FF:FF:FF:FF",
             }
         ),
+        # MAC changed but the network config contains an explicit MAC
+        # assignment. An exception is expected since Coriolis cannot
+        # modify Linux network config files at the moment.
+        (
+            [
+                {"mac_address": "00:11:22:33:44:55",
+                 "new_mac_address": "ff:aa:11:22:33:44",
+                 "ip_addresses": ["192.168.1.10"]},
+            ],
+            {
+                "eth0": {"mac_address": "00:11:22:33:44:55",
+                         "ip_addresses": []},
+            },
+            exception.CoriolisException,
+        ),
+        # The MAC address changed but the network config files did not
+        # contain explicit MAC assignments, we can rely on the udev rules
+        # that preserve the interface names. The new MAC will be returned.
+        (
+            [
+                {"mac_address": "00:11:22:33:44:55",
+                 "new_mac_address": "ff:aa:11:22:33:44",
+                 "ip_addresses": ["192.168.1.10"]},
+            ],
+            {
+                "eth0": {"mac_address": None,
+                         "ip_addresses": ["192.168.1.10"]},
+            },
+            {
+                "eth0": "ff:aa:11:22:33:44",
+            }
+        ),
     )
     @ddt.unpack
     def test__setup_network_preservation(
@@ -1912,13 +1944,22 @@ def parse_network(self):
 
             self.os_morphing_tools._add_net_udev_rules = mock.MagicMock()
 
-            with self.assertLogs(
-                'coriolis.osmorphing.base', level=logging.INFO):
-                self.os_morphing_tools._setup_network_preservation(nics_info)
+            if isinstance(expected_net_ifaces, type) and issubclass(
+                    expected_net_ifaces, Exception):
+                self.assertRaises(
+                    expected_net_ifaces,
+                    self.os_morphing_tools._setup_network_preservation,
+                    nics_info,
+                )
+            else:
+                with self.assertLogs(
+                    'coriolis.osmorphing.base', level=logging.INFO):
+                    self.os_morphing_tools._setup_network_preservation(
+                        nics_info)
 
-            result_net_ifaces = dict(
-                self.os_morphing_tools._add_net_udev_rules.call_args[0][0])
+                result_net_ifaces = dict(
+                    self.os_morphing_tools._add_net_udev_rules.call_args[0][0])
 
-            mock_get_np.assert_called_once_with(self.os_morphing_tools)
-            self.os_morphing_tools._add_net_udev_rules.assert_called_once()
-            self.assertEqual(expected_net_ifaces, result_net_ifaces)
+                mock_get_np.assert_called_once_with(self.os_morphing_tools)
+                self.os_morphing_tools._add_net_udev_rules.assert_called_once()
+                self.assertEqual(expected_net_ifaces, result_net_ifaces)