Can you federate your Enterprise Server to Portal when using Built-in Users and Built-In Groups in Portal?
Yes.
Does it copy the users and groups into Portal?
No. When you federate, any users, roles, and permissions that you previously configured on ArcGIS Server services are no longer valid. Access to services is instead determined by portal members, roles, and sharing permissions. Before federating, review the information in Administer a federated server to learn more about how federating will impact your existing site.
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