diff --git a/tcp_tests/settings_oslo.py b/tcp_tests/settings_oslo.py
index 5ba6602..7e8490d 100644
--- a/tcp_tests/settings_oslo.py
+++ b/tcp_tests/settings_oslo.py
@@ -51,8 +51,8 @@
                   }, ...]""", default=[]),
     ct.Cfg('roles', ct.JSONList(),
            help="Node roles managed by underlay in the environment",
-           default=[ext.UNDERLAY_NODE_ROLE.salt_master,
-                    ext.UNDERLAY_NODE_ROLE.salt_minion, ]),
+           default=[ext.UNDERLAY_NODE_ROLES.salt_master,
+                    ext.UNDERLAY_NODE_ROLES.salt_minion, ]),
     ct.Cfg('nameservers', ct.JSONList(),
            help="IP addresses of DNS servers",
            default=[]),