fix: match interface names cut to the NetBox name length

module/sources/common/source_base.py

@@ -188,6 +188,12 @@ def map_object_interfaces_to_current_interfaces(self, device_vm_object, interfac
         current_interfaces_by_wwn = dict()
         current_fc_interface_names = set()
 
+        # netbox-sync cuts names to the data model length when it creates an interface,
+        # compare discovered names the same way
+        interface_class = NBVMInterface if isinstance(device_vm_object, NBVM) else NBInterface
+        max_name_length = interface_class().data_model.get("name")
+        discovered_names_by_cut_name = dict()
+
         return_data = dict()
 
         # grab current data
@@ -244,11 +250,24 @@ def map_object_interfaces_to_current_interfaces(self, device_vm_object, interfac
             if "virtual" not in str(int_type_string):
                 int_type = "physical"
 
+            stored_int_name = int_name
+            if isinstance(max_name_length, int) and isinstance(int_name, str) and len(int_name) > max_name_length:
+                stored_int_name = int_name[0:max_name_length]
+                log.debug(f"Name of interface '{int_name}' exceeds {max_name_length} characters, "
+                          f"comparing it as '{stored_int_name}'")
+
+                colliding_name = discovered_names_by_cut_name.get(stored_int_name)
+                if colliding_name is not None:
+                    log.warning(f"Interfaces '{colliding_name}' and '{int_name}' of "
+                                f"'{device_vm_object.get_display_name()}' share the same first {max_name_length} "
+                                f"characters. Only one of them can exist in NetBox with that name")
+                discovered_names_by_cut_name[stored_int_name] = int_name
+
             # match simply by name
             matching_int = None
-            if int_name in current_object_interface_names:
+            if stored_int_name in current_object_interface_names:
                 log.debug2(f"Found 1:1 name match for NIC '{int_name}'")
-                matching_int = current_object_interfaces.get(int_name)
+                matching_int = current_object_interfaces.get(stored_int_name)
 
             # match by WWN when no interface of that name exists yet
             if matching_int is None and int_wwn is not None:

tests/test_interface_matching_truncated_name.py

@@ -0,0 +1,79 @@
+# -*- coding: utf-8 -*-
+#  Copyright (c) 2020 - 2026 netbox-sync team. All rights reserved.
+#
+#  netbox-sync.py
+#
+#  This work is licensed under the terms of the MIT license.
+#  For a copy, see file LICENSE.txt included in this
+#  repository or visit: <https://opensource.org/licenses/MIT>.
+
+"""Interface names longer than the NetBox limit have to match the name NetBox stored.
+
+netbox-sync cuts interface names to 64 characters when it creates them. A Lenovo XCC port is named after the
+manager model and its Redfish id, which together are longer than that. Comparing the full
+discovered name never matched the stored one, so the port was created again on every run
+and NetBox rejected it with 'Interface with this Device and Name already exists.'
+"""
+
+import logging
+
+from module.netbox.object_classes import NBInterface, NBVM, NBVMInterface
+
+XCC_PORT_NAME = "Lenovo XClarity Controller 2 (1:NIC:672cab626d845d56d397509738c8b03900c7d706)"
+
+
+def xcc_port():
+    return {XCC_PORT_NAME: {"name": XCC_PORT_NAME, "type": "other", "mgmt_only": True}}
+
+
+def test_long_name_matches_the_stored_interface(check_redfish_source):
+
+    context = check_redfish_source()
+    stored = context.inventory.add_object(
+        NBInterface, data={"name": XCC_PORT_NAME, "device": context.device, "type": "other"},
+        source=context.source)
+    assert stored.data.get("name") != XCC_PORT_NAME, "name was not cut to the NetBox limit"
+
+    data = context.source.map_object_interfaces_to_current_interfaces(context.device, xcc_port(), True)
+
+    assert data[XCC_PORT_NAME] is stored
+
+
+def test_long_name_without_stored_interface_stays_unmatched(check_redfish_source):
+
+    context = check_redfish_source()
+
+    data = context.source.map_object_interfaces_to_current_interfaces(context.device, xcc_port(), True)
+
+    assert data[XCC_PORT_NAME] is None
+
+
+def test_long_vm_interface_name_matches_the_stored_interface(check_redfish_source):
+
+    context = check_redfish_source()
+    # only the VMware source syncs VMs, the matcher reads its VM exclude filter
+    context.source.settings.vm_interface_exclude_filter = None
+    vm = context.inventory.add_object(NBVM, data={"name": "vm01"}, source=context.source)
+    name = "Network adapter 1 (" + "a" * 60 + ")"
+    stored = context.inventory.add_object(
+        NBVMInterface, data={"name": name, "virtual_machine": vm}, source=context.source)
+    assert stored.data.get("name") != name, "name was not cut to the NetBox limit"
+
+    data = context.source.map_object_interfaces_to_current_interfaces(
+        vm, {name: {"name": name, "type": "virtual"}}, True)
+
+    assert data[name] is stored
+
+
+def test_names_colliding_after_the_cut_are_reported(check_redfish_source, caplog):
+
+    context = check_redfish_source()
+    first = XCC_PORT_NAME
+    second = XCC_PORT_NAME.replace("b03900c7d706", "000000000000")
+    ports = {name: {"name": name, "type": "other", "mgmt_only": True} for name in [first, second]}
+
+    caplog.set_level(logging.WARNING, logger="NetBox-Sync")
+    context.source.map_object_interfaces_to_current_interfaces(context.device, ports, True)
+
+    warnings = [r.getMessage() for r in caplog.records if r.levelno == logging.WARNING]
+    assert any(first in message and second in message for message in warnings), warnings