Comment 0 for bug 1601910

With the shadow users implementation, federated users are no longer emphemeral. Support for specifying this option in a mapping should be removed. The option should be ignored and should result in a log that indicates a timeframe for removal (2 cycles)

See this blueprint for details: https://blueprints.launchpad.net/keystone/+spec/shadow-users-newton

See this review for a patch: https://review.openstack.org/#/c/296639/