diff --git a/nova/api/openstack/compute/attach_interfaces.py b/nova/api/openstack/compute/attach_interfaces.py
index 68e072c895..1da9ccbe92 100644
--- a/nova/api/openstack/compute/attach_interfaces.py
+++ b/nova/api/openstack/compute/attach_interfaces.py
@@ -30,9 +30,6 @@ from nova import network
 from nova.policies import attach_interfaces as ai_policies
 
 
-ALIAS = 'os-attach-interfaces'
-
-
 def _translate_interface_attachment_view(port_info):
     """Maps keys for interface attachment details view."""
     return {
@@ -177,25 +174,3 @@ class InterfaceAttachmentController(wsgi.Controller):
         except exception.InstanceInvalidState as state_error:
             common.raise_http_conflict_for_instance_invalid_state(state_error,
                     'detach_interface', server_id)
-
-
-class AttachInterfaces(extensions.V21APIExtensionBase):
-    """Attach interface support."""
-
-    name = "AttachInterfaces"
-    alias = ALIAS
-    version = 1
-
-    def get_resources(self):
-        res = [extensions.ResourceExtension('os-interface',
-                                            InterfaceAttachmentController(),
-                                            parent=dict(
-                                                member_name='server',
-                                                collection_name='servers'))]
-        return res
-
-    def get_controller_extensions(self):
-        """It's an abstract function V21APIExtensionBase and the extension
-        will not be loaded without it.
-        """
-        return []
diff --git a/nova/api/openstack/compute/routes.py b/nova/api/openstack/compute/routes.py
index 7b53cc12fe..0e3a4acf26 100644
--- a/nova/api/openstack/compute/routes.py
+++ b/nova/api/openstack/compute/routes.py
@@ -22,6 +22,7 @@ from nova.api.openstack.compute import admin_password
 from nova.api.openstack.compute import agents
 from nova.api.openstack.compute import aggregates
 from nova.api.openstack.compute import assisted_volume_snapshots
+from nova.api.openstack.compute import attach_interfaces
 from nova.api.openstack.compute import availability_zone
 from nova.api.openstack.compute import certificates
 from nova.api.openstack.compute import config_drive
@@ -216,6 +217,10 @@ server_metadata_controller = functools.partial(_create_controller,
     server_metadata.ServerMetadataController, [], [])
 
 
+server_os_interface_controller = functools.partial(_create_controller,
+    attach_interfaces.InterfaceAttachmentController, [], [])
+
+
 server_password_controller = functools.partial(_create_controller,
     server_password.ServerPasswordController, [], [])
 
@@ -420,6 +425,14 @@ ROUTE_LIST = (
         'PUT': [server_metadata_controller, 'update'],
         'DELETE': [server_metadata_controller, 'delete'],
     }),
+    ('/servers/{server_id}/os-interface', {
+        'GET': [server_os_interface_controller, 'index'],
+        'POST': [server_os_interface_controller, 'create']
+    }),
+    ('/servers/{server_id}/os-interface/{id}', {
+        'GET': [server_os_interface_controller, 'show'],
+        'DELETE': [server_os_interface_controller, 'delete']
+    }),
     ('/servers/{server_id}/os-server-password', {
         'GET': [server_password_controller, 'index'],
         'DELETE': [server_password_controller, 'clear']
diff --git a/setup.cfg b/setup.cfg
index 3faab7c92c..71ef2f8c37 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -72,7 +72,6 @@ wsgi_scripts =
     nova-metadata-wsgi = nova.api.metadata.wsgi:init_application
 
 nova.api.v21.extensions =
-    attach_interfaces = nova.api.openstack.compute.attach_interfaces:AttachInterfaces
     baremetal_nodes = nova.api.openstack.compute.baremetal_nodes:BareMetalNodes
     block_device_mapping = nova.api.openstack.compute.block_device_mapping:BlockDeviceMapping
     cells = nova.api.openstack.compute.cells:Cells