diff --git a/ironic/api/__init__.py b/ironic/api/__init__.py
index 71277b2814..eba90ad5b5 100644
--- a/ironic/api/__init__.py
+++ b/ironic/api/__init__.py
@@ -29,7 +29,6 @@ API_SERVICE_OPTS = [
                help=_('The maximum number of items returned in a single '
                       'response from a collection resource.')),
     cfg.StrOpt('public_endpoint',
-               default=None,
                help=_("Public URL to use when building the links to the API "
                       "resources (for example, \"https://ironic.rocks:6384\")."
                       " If None the links will be built using the request's "
diff --git a/ironic/drivers/modules/oneview/common.py b/ironic/drivers/modules/oneview/common.py
index 36bb272857..05af0bdd26 100644
--- a/ironic/drivers/modules/oneview/common.py
+++ b/ironic/drivers/modules/oneview/common.py
@@ -44,7 +44,6 @@ opts = [
                 default=False,
                 help=_('Option to allow insecure connection with OneView')),
     cfg.StrOpt('tls_cacert_file',
-               default=None,
                help=_('Path to CA certificate')),
     cfg.IntOpt('max_polling_attempts',
                default=12,
diff --git a/ironic_tempest_plugin/config.py b/ironic_tempest_plugin/config.py
index 36d59dfffb..e39f8f883a 100644
--- a/ironic_tempest_plugin/config.py
+++ b/ironic_tempest_plugin/config.py
@@ -67,7 +67,6 @@ BaremetalGroup = [
     #                 "Takes longer since Kilo as Ironic performs an extra "
     #                 "step in Node cleaning.")
     cfg.StrOpt('min_microversion',
-               default=None,
                help="Lower version of the test target microversion range. "
                     "The format is 'X.Y', where 'X' and 'Y' are int values. "
                     "Tempest selects tests based on the range between "