Hi, root causers (assuming this nickname has been agreed) It seems the placeholder is created for every neighbor of an entity[1]. I'm not sure what will happen if the neighbor entity has been created before. Will the graph utility handle it? Or we need to check the existence in transformer and deal with it? Similar question for how to create a vertex when there is already a placeholder with same ID [1]: https://github.com/openstack/vitrage/blob/master/vitrage/datasources/static_physical/transformer.py#L114 -- Yujun -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20161214/0d91d5f3/attachment.html>