Drupal has been one of the most popular content management systems in the current digital market scenario. A large community of developers and other contributors are working together to improve the functionality and performance of Drupal CMS solutions. And that is why the Drupal users have been receiving frequent updates or releases for bug fixing and software upgrading. If you are new to the Drupal web development scenario and wondering how to update Drupal core to a new minor version within the same major release series, then let us help you out with some step-by-step instructions.
Take a backup of your Drupal database
Download the latest release of your existing Drupal version
Extract the tar ball or zip file of Drupal package
Change your website to maintenance mode
You need to delete all the files and folders in your original Drupal database, except the /sites and its subfolders. Retaining these files helps to save your custom work, including themes, in the preferred location (/sites folder tree). Make it a point to either replace or save the customized works before starting the upgrade process.
Copy all the folders and files (except /sites) from the extracted Drupal package and paste in your original Drupal instance location.
Check whether the new update release includes changes to settings.php. If yes, then replace the settings.php file in your original Drupal instance by editing the /sites/default/ details such as database name, user and password.
If you have made changes to the .htaccess and robots.txt files, then re-apply the modifications to the new files.
Replace the favicon.ico file, if your website had any and was deleted during the upgrade
Login to your Drupal website as an administrator or user no. 1
You need to run update.php by navigating to ‘https://www.drupal.org/upgrade’ and follow the process to update your original Drupal instance
Last but not the least, disable the maintenance mode.
You may find detailed yet complex instructions regarding the update in the Administration and Security Guide available on the official website of Drupal. Despite the above mentioned steps, you may also have alternatives to upgrade the Drupal by using Drush or by using a patch file.