Comment 1 for bug 1671265

I believe that even Juju 2.1 runs nova with the security group name rather than its ID, so it seems to me that this will probably break even with 2.1 on the model, but I can't prove that at the moment. My guess is that you can reproduce by creating an OpenStack-based model with 2.0, then upgrading the controller to 2.1, then trying to deploy anything more to the model.