Managing configuration within Drupal does not always involve changing settings within the administrative panels of a specific section. In fact, Drupal also allows various settings to be configured within the settings.php file. Configuration settings within the settings.php file act as global overrides to those in the database. Some settings, as we will see, can only be set or modified from the settings.php file.
The settings.php file can be located within the /sites/default folder of a Drupal installation.
Keep in mind that the file permissions are set to read only; so, it is important to temporarily modify the permissions to be writeable before making any changes.
Once we have made the settings.php file writeable, we can open it within our favorite editor and locate the Configuration overrides section:
Reading through the Configuration overrides...