Description of problem: Encountered an issue Version-Release number of selected component (if applicable): 10-z How reproducible: 100% Steps to Reproduce: 1. Create an environment file with .yml extension 2. Run an openstack command using the environment file Actual results: Various errors (depending on usage) which aren't clear as to cause (e.g."Failed to validate: Failed to validate: resources[0]: The Resource Type (OS::TripleO::Controller::Net::SoftwareConfig) could not be found.") Expected results: Working command Additional info: This bz requests adding a note similar to: https://docs.openstack.org/heat/newton/template_guide/environment.html#override-a-resource-with-a-custom-resource: "Note The template file extension must be .yaml or .template, or it will not be treated as a custom template resource." Once the file(s) were renamed from the incorrect suffix (.yml) to the correct suffix (.yaml), the openstack commands worked as expected For occasional OpenStack users, this can be extremely vexing