diff --git a/nova/virt/libvirt/driver.py b/nova/virt/libvirt/driver.py
index 5719f1f1736..6587e7e20d0 100644
--- a/nova/virt/libvirt/driver.py
+++ b/nova/virt/libvirt/driver.py
@@ -6351,6 +6351,11 @@ def finish_migration(self, context, migration, instance, disk_info,
                                   image_meta,
                                   block_device_info=block_device_info,
                                   write_to_disk=True)
+        # NOTE(mriedem): vifs_already_plugged=True here, regardless of whether
+        # or not we've migrated to another host, because we unplug VIFs locally
+        # and the status change in the port might go undetected by the neutron
+        # L2 agent (or neutron server) so neutron may not know that the VIF was
+        # unplugged in the first place and never send an event.
         self._create_domain_and_network(context, xml, instance, network_info,
                                         disk_info,
                                         block_device_info=block_device_info,