When using the --os-image command from python-tripleoclient, that gets translated into the OS_IMAGE env var:

757 parser.add_argument(
758 "--os-image",
759 default=os.environ.get('OS_IMAGE', 'overcloud-full.qcow2'),
760 help=_("OpenStack disk image filename"),

But when we try to use it, we are getting this error:

image version overcloud-full.qcow2 is not in supported versions 1, 2
Invalid image client version 'overcloud-full.qcow2'. must be one of: 1, 2

That is actually because OS_IMAGE env var ends somehow being part of os_client_config in the openstackclient:

{'auth_type': 'password', 'beta_command': False, 'tripleoclient_api_version': '1', u'compute_api_version': u'2', 'key': None, u'database_api_version': u'1.0', 'metrics_api_version': '1', 'data_proce
ssing_api_version': '1.1', 'inspector_api_version': '1', 'auth_url': 'http://192.168.24.1:5000/v2.0', u'network_api_version': u'2', u'message': u'', u'image_format': u'qcow2', 'networks': [], u'imag
e_api_version': u'overcloud-full.qcow2' }

This bug has been tested with stable/newton