diff --git a/cloud/openstack/os_server.py b/cloud/openstack/os_server.py
index 959f39880f8..90cc7282d04 100644
--- a/cloud/openstack/os_server.py
+++ b/cloud/openstack/os_server.py
@@ -392,7 +392,7 @@ def main():
         flavor_include                  = dict(default=None),
         key_name                        = dict(default=None),
         security_groups                 = dict(default='default'),
-        nics                            = dict(default=[]),
+        nics                            = dict(default=[], type='list'),
         meta                            = dict(default=None),
         userdata                        = dict(default=None),
         config_drive                    = dict(default=False, type='bool'),