diff --git a/core/includes/install.inc b/core/includes/install.inc
index 162d9c905b9e6b9e2e96e8e39b6b6c436d0f31a7..c9fd75d211e160f0da88e88632b86cfcc4c2bc9b 100644
--- a/core/includes/install.inc
+++ b/core/includes/install.inc
@@ -210,7 +210,6 @@ function drupal_get_database_types() {
  *   @endcode
  *   gets dumped as:
  *   @code
- *   $config_directories['active'] = 'config_hash/active';
  *   $config_directories['sync'] = 'config_hash/sync'
  *   @endcode
  */
@@ -524,8 +523,7 @@ function drupal_install_config_directories() {
  * Ensures that the config directory exists and is writable, or can be made so.
  *
  * @param string $type
- *   Type of config directory to return. Drupal core provides 'active' and
- *   'sync'.
+ *   Type of config directory to return. Drupal core provides 'sync'.
  *
  * @return bool
  *   TRUE if the config directory exists and is writable.
diff --git a/sites/default/default.settings.php b/sites/default/default.settings.php
index b1f95e20183788814f1cbe15864b30887bc7823a..1a6d148006a084c75ff6a668cee7efdf66a2b15a 100644
--- a/sites/default/default.settings.php
+++ b/sites/default/default.settings.php
@@ -223,22 +223,24 @@
  * Location of the site configuration files.
  *
  * The $config_directories array specifies the location of file system
- * directories used for configuration data. On install, "active" and "sync"
- * directories are created for configuration. The sync directory is used for
- * configuration imports; the active directory is not used by default, since the
- * default storage for active configuration is the database rather than the file
- * system (this can be changed; see "Active configuration settings" below).
- *
- * The default location for the active and sync directories is inside a
- * randomly-named directory in the public files path; this setting allows you to
- * override these locations. If you use files for the active configuration, you
- * can enhance security by putting the active configuration outside your
- * document root.
+ * directories used for configuration data. On install, the "sync" directory is
+ * created. This is used for configuration imports. The "active" directory is
+ * not created by default since the default storage for active configuration is
+ * the database rather than the file system. (This can be changed. See "Active
+ * configuration settings" below).
+ *
+ * The default location for the "sync" directory is inside a randomly-named
+ * directory in the public files path. The setting below allows you to override
+ * the "sync" location.
+ *
+ * If you use files for the "active" configuration, you can tell the
+ * Configuration system where this directory is located by adding an entry with
+ * array key CONFIG_ACTIVE_DIRECTORY.
  *
  * Example:
  * @code
  *   $config_directories = array(
- *     CONFIG_SYNC_DIRECTORY => '/another/directory/outside/webroot',
+ *     CONFIG_SYNC_DIRECTORY => '/directory/outside/webroot',
  *   );
  * @endcode
  */
@@ -580,6 +582,10 @@
  * By default, the active configuration is stored in the database in the
  * {config} table. To use a different storage mechanism for the active
  * configuration, do the following prior to installing:
+ * - Create an "active" directory and declare its path in $config_directories
+ *   as explained under the 'Location of the site configuration files' section
+ *   above in this file. To enhance security, you can declare a path that is
+ *   outside your document root.
  * - Override the 'bootstrap_config_storage' setting here. It must be set to a
  *   callable that returns an object that implements
  *   \Drupal\Core\Config\StorageInterface.