diff --git a/magnum/tests/functional/common/config.py b/magnum/tests/functional/common/config.py
index c5cc2cc854..646f5369fe 100644
--- a/magnum/tests/functional/common/config.py
+++ b/magnum/tests/functional/common/config.py
@@ -10,8 +10,11 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+import warnings
+
 from tempest import config
 
+from oslo_config import cfg
 
 CONF = config.CONF
 
@@ -24,7 +27,14 @@ class Config(object):
     def set_admin_creds(cls, config):
         cls.admin_user = CONF.auth.admin_username
         cls.admin_passwd = CONF.auth.admin_password
-        cls.admin_tenant = CONF.auth.admin_project_name
+        # NOTE(toabctl): also allow the old style tempest definition
+        try:
+            cls.admin_tenant = CONF.auth.admin_project_name
+        except cfg.NoSuchOptError:
+            cls.admin_tenant = CONF.auth.admin_tenant_name
+            warnings.warn("the config option 'admin_tenant_name' from the "
+                          "'auth' section is deprecated. Please switch "
+                          "to 'admin_project_name'.")
 
     @classmethod
     def set_user_creds(cls, config):
@@ -36,7 +46,14 @@ class Config(object):
         # check Ia5132c5cb32355d6f26b8acdd92a0e55a2c19f41
         cls.user = CONF.auth.admin_username
         cls.passwd = CONF.auth.admin_password
-        cls.tenant = CONF.auth.admin_project_name
+        # NOTE(toabctl): also allow the old style tempest definition
+        try:
+            cls.tenant = CONF.auth.admin_project_name
+        except cfg.NoSuchOptError:
+            cls.tenant = CONF.auth.admin_tenant_name
+            warnings.warn("the config option 'admin_tenant_name' from the "
+                          "'auth' section is deprecated. Please switch "
+                          "to 'admin_project_name'.")
 
     @classmethod
     def set_auth_version(cls, config):