While I tend to play up bug 968696 for dramatic effect, the reality is we have a logical contradiction on what we mean by ‘admin’ when talking about RBAC.

In early iterations of OpenStack, roles were global. This is reflected in many of the Policy checks that only look for the global role. However, prior to the Keystone-Light rewrite, role assignments became scoped to tenants. This shows up in the Keystone git history. As this pattern got established, some people wrote policy checks that assert:

role==admin and tenant_id=resource.tenant_id

This contradicts the global-ness of the admin roles. If I assign

(‘joeuser’, ‘admin’,’mytenant’)

I’ve just granted them the ability to perform all of the admin operations.

Thus, today we have a situation where, unless the user rewrites the default policy, they have to only assign the role admins to users that are trusted to be admins on the whole deployment.

We have a few choices.
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