Summary
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References:

#. https://etherpad.openstack.org/p/tripleo-composable-roles-work

#. https://review.openstack.org/#/c/245804/2/specs/mitaka/composable-services-within-roles.rst

#. https://review.openstack.org/#/q/topic:composable_service

#. https://docs.openstack.org/tripleo-docs/latest/install/advanced_deployment/template_deploy.html

#. http://hardysteven.blogspot.com.es/2015/05/tripleo-heat-templates-part-1-roles-and.html

#. http://hardysteven.blogspot.com.es/2015/05/tripleo-heat-templates-part-2-node.html

#. http://hardysteven.blogspot.com.es/2015/05/tripleo-heat-templates-part-3-cluster.html