diff --git a/src/libnm-core-impl/nm-setting-connection.c b/src/libnm-core-impl/nm-setting-connection.c
index 892e7d3151..8066cb0930 100644
--- a/src/libnm-core-impl/nm-setting-connection.c
+++ b/src/libnm-core-impl/nm-setting-connection.c
@@ -2458,7 +2458,8 @@ nm_setting_connection_class_init(NMSettingConnectionClass *klass)
         NMSettingConnectionPrivate,
         controller,
         .direct_string_allow_empty = TRUE,
-        .is_deprecated             = TRUE);
+        .is_deprecated             = TRUE,
+        .direct_is_aliased_field   = TRUE, );
 
     /**
      * NMSettingConnection:controller:
@@ -2518,8 +2519,9 @@ nm_setting_connection_class_init(NMSettingConnectionClass *klass)
                                            _nm_setting_connection_slave_type_from_dbus, ),
         NMSettingConnectionPrivate,
         port_type,
-        .is_deprecated             = 1,
-        .direct_string_allow_empty = TRUE);
+        .is_deprecated             = TRUE,
+        .direct_string_allow_empty = TRUE,
+        .direct_is_aliased_field   = TRUE, );
 
     /**
      * NMSettingConnection:port-type:
diff --git a/src/libnm-core-impl/nm-setting.c b/src/libnm-core-impl/nm-setting.c
index 758338e5ce..a51d0a228a 100644
--- a/src/libnm-core-impl/nm-setting.c
+++ b/src/libnm-core-impl/nm-setting.c
@@ -1077,7 +1077,7 @@ _init_direct(NMSetting *setting)
             int  def_val;
 
             def_val = NM_G_PARAM_SPEC_GET_DEFAULT_ENUM(property_info->param_spec);
-            nm_assert(*p_val == 0);
+            nm_assert(NM_IN_SET(*p_val, 0, property_info->direct_is_aliased_field ? def_val : 0));
             *p_val = def_val;
             break;
         }
diff --git a/src/libnm-core-intern/nm-core-internal.h b/src/libnm-core-intern/nm-core-internal.h
index 8e2573370b..dedc90b240 100644
--- a/src/libnm-core-intern/nm-core-internal.h
+++ b/src/libnm-core-intern/nm-core-internal.h
@@ -907,6 +907,14 @@ struct _NMSettInfoProperty {
      * is not deprecated. This flag is about the deprecation of the D-Bus representation
      * of a property. */
     bool dbus_deprecated : 1;
+
+    /* Whether the property is an alias.
+     *
+     * This flag indicates whether a property is an alias of another. This is used
+     * during _init_direct() to allow two or more properties to set the value of
+     * the same field.
+     */
+    bool direct_is_aliased_field : 1;
 };
 
 typedef struct {