Comment 3 for bug 1634453

I am getting the same error from a devstack I just created. As demo user and admin user, whenever I bring up a launch instance dialog from the instance page or the images page, I get this error message.

No problem when using the CLI "openstack flavor list". As admin, in the Admin->flavors page in Horizon, I see all flavors as well.

Under /var/log/apache2, I find no error around the time I try to launch the instance. horizon_error.log does mention cookies being too large and recommends switching to "file or database-backed sessions". I don't know how to do that, though. It also has a warning:

oslo_policy.policy:Policies ['update_rbac_policy:target_tenant'] are part of a cyclical reference

Where should I look for errors?