Add parent field to Interface

netbox/dcim/api/serializers.py

@@ -598,6 +598,7 @@ class InterfaceSerializer(TaggedObjectSerializer, CableTerminationSerializer, Co
     url = serializers.HyperlinkedIdentityField(view_name='dcim-api:interface-detail')
     device = NestedDeviceSerializer()
     type = ChoiceField(choices=InterfaceTypeChoices)
+    parent = NestedInterfaceSerializer(required=False, allow_null=True)
     lag = NestedInterfaceSerializer(required=False, allow_null=True)
     mode = ChoiceField(choices=InterfaceModeChoices, allow_blank=True, required=False)
     untagged_vlan = NestedVLANSerializer(required=False, allow_null=True)
@@ -613,10 +614,11 @@ class InterfaceSerializer(TaggedObjectSerializer, CableTerminationSerializer, Co
     class Meta:
         model = Interface
         fields = [
-            'id', 'url', 'device', 'name', 'label', 'type', 'enabled', 'lag', 'mtu', 'mac_address', 'mgmt_only',
+            'id', 'url', 'device', 'name', 'label', 'type', 'enabled', 'parent', 'lag', 'mtu', 'mac_address',
-            'description', 'mode', 'untagged_vlan', 'tagged_vlans', 'mark_connected', 'cable', 'cable_peer',
+            'mgmt_only', 'description', 'mode', 'untagged_vlan', 'tagged_vlans', 'mark_connected', 'cable',
-            'cable_peer_type', 'connected_endpoint', 'connected_endpoint_type', 'connected_endpoint_reachable', 'tags',
+            'cable_peer', 'cable_peer_type', 'connected_endpoint', 'connected_endpoint_type',
-            'custom_fields', 'created', 'last_updated', 'count_ipaddresses', '_occupied',
+            'connected_endpoint_reachable', 'tags', 'custom_fields', 'created', 'last_updated', 'count_ipaddresses',
+            '_occupied',
         ]
 
     def validate(self, data):

netbox/dcim/api/views.py

@@ -522,7 +522,7 @@ class PowerOutletViewSet(PathEndpointMixin, ModelViewSet):
 
 class InterfaceViewSet(PathEndpointMixin, ModelViewSet):
     queryset = Interface.objects.prefetch_related(
-        'device', '_path__destination', 'cable', '_cable_peer', 'ip_addresses', 'tags'
+        'device', 'parent', 'lag', '_path__destination', 'cable', '_cable_peer', 'ip_addresses', 'tags'
     )
     serializer_class = serializers.InterfaceSerializer
     filterset_class = filters.InterfaceFilterSet

netbox/dcim/filters.py

@@ -844,6 +844,11 @@ class InterfaceFilterSet(BaseFilterSet, DeviceComponentFilterSet, CableTerminati
         method='filter_kind',
         label='Kind of interface',
     )
+    parent_id = django_filters.ModelMultipleChoiceFilter(
+        field_name='parent',
+        queryset=Interface.objects.all(),
+        label='Parent interface (ID)',
+    )
     lag_id = django_filters.ModelMultipleChoiceFilter(
         field_name='lag',
         queryset=Interface.objects.all(),

netbox/dcim/forms.py

@@ -2830,8 +2830,8 @@ class InterfaceForm(BootstrapMixin, InterfaceCommonForm, CustomFieldModelForm):
     class Meta:
         model = Interface
         fields = [
-            'device', 'name', 'label', 'type', 'enabled', 'lag', 'mac_address', 'mtu', 'mgmt_only', 'mark_connected',
+            'device', 'name', 'label', 'type', 'enabled', 'parent', 'lag', 'mac_address', 'mtu', 'mgmt_only',
-            'description', 'mode', 'untagged_vlan', 'tagged_vlans', 'tags',
+            'mark_connected', 'description', 'mode', 'untagged_vlan', 'tagged_vlans', 'tags',
         ]
         widgets = {
             'device': forms.HiddenInput(),
@@ -2854,10 +2854,16 @@ class InterfaceForm(BootstrapMixin, InterfaceCommonForm, CustomFieldModelForm):
         else:
             device = self.instance.device
 
-        # Limit LAG choices to interfaces belonging to this device or a peer VC member
         device_query = Q(device=device)
         if device.virtual_chassis:
             device_query |= Q(device__virtual_chassis=device.virtual_chassis)
+
+        # Limit parent interface choices to interfaces belonging to this device or a peer VC member
+        self.fields['parent'].queryset = Interface.objects.filter(device_query).exclude(
+            type__in=(InterfaceTypeChoices.TYPE_VIRTUAL, InterfaceTypeChoices.TYPE_LAG)
+        ).exclude(pk=self.instance.pk)
+
+        # Limit LAG choices to interfaces belonging to this device or a peer VC member
         self.fields['lag'].queryset = Interface.objects.filter(
             device_query,
             type=InterfaceTypeChoices.TYPE_LAG
@@ -2878,6 +2884,12 @@ class InterfaceCreateForm(ComponentCreateForm, InterfaceCommonForm):
         required=False,
         initial=True
     )
+    parent = forms.ModelChoiceField(
+        queryset=Interface.objects.all(),
+        required=False,
+        label='Parent interface',
+        widget=StaticSelect2(),
+    )
     lag = forms.ModelChoiceField(
         queryset=Interface.objects.all(),
         required=False,
@@ -2923,20 +2935,25 @@ class InterfaceCreateForm(ComponentCreateForm, InterfaceCommonForm):
         }
     )
     field_order = (
-        'device', 'name_pattern', 'label_pattern', 'type', 'enabled', 'lag', 'mtu', 'mac_address', 'description',
+        'device', 'name_pattern', 'label_pattern', 'type', 'enabled', 'parent', 'lag', 'mtu', 'mac_address',
-        'mgmt_only', 'mark_connected', 'mode', 'untagged_vlan', 'tagged_vlans', 'tags'
+        'description', 'mgmt_only', 'mark_connected', 'mode', 'untagged_vlan', 'tagged_vlans', 'tags'
     )
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
-
-        # Limit LAG choices to interfaces belonging to this device or a peer VC member
         device = Device.objects.get(
             pk=self.initial.get('device') or self.data.get('device')
         )
         device_query = Q(device=device)
         if device.virtual_chassis:
             device_query |= Q(device__virtual_chassis=device.virtual_chassis)
+
+        # Limit parent interface choices to interfaces belonging to this device or a peer VC member
+        self.fields['parent'].queryset = Interface.objects.filter(device_query).exclude(
+            type__in=(InterfaceTypeChoices.TYPE_VIRTUAL, InterfaceTypeChoices.TYPE_LAG)
+        )
+
+        # Limit LAG choices to interfaces belonging to this device or a peer VC member
         self.fields['lag'].queryset = Interface.objects.filter(device_query, type=InterfaceTypeChoices.TYPE_LAG)
 
         # Add current site to VLANs query params
@@ -2956,7 +2973,7 @@ class InterfaceBulkCreateForm(
 
 class InterfaceBulkEditForm(
     form_from_model(Interface, [
-        'label', 'type', 'lag', 'mac_address', 'mtu', 'mgmt_only', 'mark_connected', 'description', 'mode'
+        'label', 'type', 'parent', 'lag', 'mac_address', 'mtu', 'mgmt_only', 'mark_connected', 'description', 'mode',
     ]),
     BootstrapMixin,
     AddRemoveTagsForm,
@@ -3006,7 +3023,7 @@ class InterfaceBulkEditForm(
 
     class Meta:
         nullable_fields = [
-            'label', 'lag', 'mac_address', 'mtu', 'description', 'mode', 'untagged_vlan', 'tagged_vlans'
+            'label', 'parent', 'lag', 'mac_address', 'mtu', 'description', 'mode', 'untagged_vlan', 'tagged_vlans'
         ]
 
     def __init__(self, *args, **kwargs):
@@ -3024,7 +3041,7 @@ class InterfaceBulkEditForm(
             self.fields['untagged_vlan'].widget.add_query_param('site_id', device.site.pk)
             self.fields['tagged_vlans'].widget.add_query_param('site_id', device.site.pk)
         else:
-            # See 4523
+            # See #4523
             if 'pk' in self.initial:
                 site = None
                 interfaces = Interface.objects.filter(pk__in=self.initial['pk']).prefetch_related('device__site')
@@ -3064,6 +3081,12 @@ class InterfaceCSVForm(CustomFieldModelCSVForm):
         queryset=Device.objects.all(),
         to_field_name='name'
     )
+    parent = CSVModelChoiceField(
+        queryset=Interface.objects.all(),
+        required=False,
+        to_field_name='name',
+        help_text='Parent interface'
+    )
     lag = CSVModelChoiceField(
         queryset=Interface.objects.all(),
         required=False,

netbox/dcim/migrations/0129_interface_parent.py

@@ -0,0 +1,17 @@
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('dcim', '0128_device_location_populate'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='interface',
+            name='parent',
+            field=models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.SET_NULL, related_name='child_interfaces', to='dcim.interface'),
+        ),
+    ]

netbox/dcim/models/device_components.py

@@ -523,6 +523,14 @@ class Interface(ComponentModel, BaseInterface, CableTermination, PathEndpoint):
         max_length=100,
         blank=True
     )
+    parent = models.ForeignKey(
+        to='self',
+        on_delete=models.SET_NULL,
+        related_name='child_interfaces',
+        null=True,
+        blank=True,
+        verbose_name='Parent interface'
+    )
     lag = models.ForeignKey(
         to='self',
         on_delete=models.SET_NULL,
@@ -563,8 +571,8 @@ class Interface(ComponentModel, BaseInterface, CableTermination, PathEndpoint):
     tags = TaggableManager(through=TaggedItem)
 
     csv_headers = [
-        'device', 'name', 'label', 'lag', 'type', 'enabled', 'mark_connected', 'mac_address', 'mtu', 'mgmt_only',
+        'device', 'name', 'label', 'parent', 'lag', 'type', 'enabled', 'mark_connected', 'mac_address', 'mtu',
-        'description', 'mode',
+        'mgmt_only', 'description', 'mode',
     ]
 
     class Meta:
@@ -579,6 +587,7 @@ class Interface(ComponentModel, BaseInterface, CableTermination, PathEndpoint):
             self.device.identifier if self.device else None,
             self.name,
             self.label,
+            self.parent.name if self.parent else None,
             self.lag.name if self.lag else None,
             self.get_type_display(),
             self.enabled,
@@ -602,6 +611,27 @@ class Interface(ComponentModel, BaseInterface, CableTermination, PathEndpoint):
                         "Disconnect the interface or choose a suitable type."
             })
 
+        # An interface's parent must belong to the same device or virtual chassis
+        if self.parent and self.parent.device != self.device:
+            if self.device.virtual_chassis is None:
+                raise ValidationError({
+                    'parent': f"The selected parent interface ({self.parent}) belongs to a different device "
+                              f"({self.parent.device})."
+                })
+            elif self.parent.device.virtual_chassis != self.parent.virtual_chassis:
+                raise ValidationError({
+                    'parent': f"The selected parent interface ({self.parent}) belongs to {self.parent.device}, which "
+                              f"is not part of virtual chassis {self.device.virtual_chassis}."
+                })
+
+        # A physical interface cannot have a parent interface
+        if self.type != InterfaceTypeChoices.TYPE_VIRTUAL and self.parent is not None:
+            raise ValidationError({'parent': "Only virtual interfaces may be assigned to a parent interface."})
+
+        # A virtual interface cannot be a parent interface
+        if self.parent is not None and self.parent.type == InterfaceTypeChoices.TYPE_VIRTUAL:
+            raise ValidationError({'parent': "Virtual interfaces may not be parents of other interfaces."})
+
         # An interface's LAG must belong to the same device or virtual chassis
         if self.lag and self.lag.device != self.device:
             if self.device.virtual_chassis is None:

netbox/dcim/tables/devices.py

@@ -436,6 +436,10 @@ class DeviceInterfaceTable(InterfaceTable):
                       '{% endif %}"></i> <a href="{{ record.get_absolute_url }}">{{ value }}</a>',
         attrs={'td': {'class': 'text-nowrap'}}
     )
+    parent = tables.Column(
+        linkify=True,
+        verbose_name='Parent'
+    )
     lag = tables.Column(
         linkify=True,
         verbose_name='LAG'
@@ -449,13 +453,13 @@ class DeviceInterfaceTable(InterfaceTable):
     class Meta(DeviceComponentTable.Meta):
         model = Interface
         fields = (
-            'pk', 'name', 'label', 'enabled', 'type', 'lag', 'mgmt_only', 'mtu', 'mode', 'mac_address', 'description',
+            'pk', 'name', 'label', 'enabled', 'type', 'parent', 'lag', 'mgmt_only', 'mtu', 'mode', 'mac_address',
-            'mark_connected', 'cable', 'cable_peer', 'connection', 'tags', 'ip_addresses', 'untagged_vlan',
+            'description', 'mark_connected', 'cable', 'cable_peer', 'connection', 'tags', 'ip_addresses',
-            'tagged_vlans', 'actions',
+            'untagged_vlan', 'tagged_vlans', 'actions',
         )
         default_columns = (
-            'pk', 'name', 'label', 'enabled', 'type', 'lag', 'mtu', 'mode', 'description', 'ip_addresses', 'cable',
+            'pk', 'name', 'label', 'enabled', 'type', 'parent', 'lag', 'mtu', 'mode', 'description', 'ip_addresses',
-            'connection', 'actions',
+            'cable', 'connection', 'actions',
         )
         row_attrs = {
             'class': lambda record: record.cable.get_status_class() if record.cable else '',

netbox/templates/dcim/interface.html

@@ -38,10 +38,20 @@
                             {% endif %}
                         </td>
                     </tr>
+                    <tr>
+                        <td>Parent</td>
+                        <td>
+                            {% if object.parent %}
+                                <a href="{{ object.parent.get_absolute_url }}">{{ object.parent }}</a>
+                            {% else %}
+                                <span class="text-muted">None</span>
+                            {% endif %}
+                        </td>
+                    </tr>
                     <tr>
                         <td>LAG</td>
                         <td>
-                            {% if object.lag%}
+                            {% if object.lag %}
                                 <a href="{{ object.lag.get_absolute_url }}">{{ object.lag }}</a>
                             {% else %}
                                 <span class="text-muted">None</span>