INTRODUCTION
------------
This document describes how to update your Drupal site between 8.x.x minor and
patch versions; for example, from 8.1.2 to 8.1.3, or from 8.3.5 to 8.4.0.

To upgrade from a previous major version (for example, Drupal 6 or 7), the
process involves importing site configuration and content from your old site
into a new Drupal 8 site. The tools and process are currently experimental,
rather than being fully supported, so be sure to test in a development
environment. You will need to use the core Migrate Drupal UI module which
provides a user interface for the Migrate and Migrate Drupal modules included
in core. See https://www.drupal.org/upgrade/migrate for details, and
https://www.drupal.org/node/2167633 for known issues.

First steps and definitions:

  * If you are upgrading to Drupal version x.y.z, then x is known as the major
    version number, y is known as the minor version number, and z is known as
    the patch version number. The download file will be named
    drupal-x.y.z.tar.gz (or drupal-x.y.z.zip). Previous Drupal versions used
    only x.y (MAJOR.MINOR) to designate their versions.

  * All directories mentioned in this document are relative to the directory of
    your Drupal installation.

  * Make a full backup of all files, directories, and your database(s) before
    starting, and save it outside your Drupal installation directory.
    Instructions may be found at
    https://www.drupal.org/upgrade/backing-up-the-db

  * It is wise to try an update or upgrade on a test copy of your site before
    applying it to your live site. Even minor updates can cause your site's
    behavior to change.

  * Each new release of Drupal has release notes, which explain the changes made
    since the previous version and any special instructions needed to update or
    upgrade to the new version. You can find a link to the release notes for the
    version you are upgrading or updating to on the Drupal project page
    (https://www.drupal.org/project/drupal).

UPDATE PROBLEMS
----------------
If you encounter errors during this process,

  * Note any error messages you see.

  * Restore your site to its previous state, using the file and database backups
    you created before you started the update process. Do not attempt to do
    further updates on a site that had update problems.

  * Consult one of the support options listed on https://www.drupal.org/support

More in-depth information on updating and upgrading can be found at
https://www.drupal.org/upgrade

MINOR AND PATCH VERSION UPDATES
-------------------------------
To update from one 8.x.x version of Drupal to any later 8.x.x version, after
following the instructions in the INTRODUCTION section at the top of this file:

1. Log in as a user with the permission "Administer software updates".

2. Go to Administration > Configuration > Development > Maintenance mode.
   Enable the "Put site into maintenance mode" checkbox and save the
   configuration.

3. Remove the 'core' and 'vendor' directories. Also remove all of the files
   in the top-level directory, except any that you added manually.

   If you made modifications to files like .htaccess, composer.json, or
   robots.txt you will need to re-apply them from your backup, after the new
   files are in place.

   Sometimes an update includes changes to default.settings.php (this will be
   noted in the release notes). If that's the case, follow these steps:

   - Locate your settings.php file in the /sites/* directory. (Typically
     sites/default.)

   - Make a backup copy of your settings.php file, with a different file name.

   - Make a copy of the new default.settings.php file, and name the copy
     settings.php (overwriting your previous settings.php file).

   - Copy the custom and site-specific entries from the backup you made into the
     new settings.php file. You will definitely need the lines giving the
     database information, and you will also want to copy in any other
     customizations you have added.

   You can find the release notes for your version at
   https://www.drupal.org/project/drupal. At bottom of the project page under
   "Downloads" use the link for your version of Drupal to view the release
   notes. If your version is not listed, use the 'View all releases' link. From
   this page you can scroll down or use the filter to find your version and its
   release notes.

4. Download the latest Drupal 8.x.x release from https://www.drupal.org to a
   directory outside of your web root. Extract the archive and copy the files
   into your Drupal directory.

   On a typical Unix/Linux command line, use the following commands to download
   and extract:

     wget https://www.drupal.org/files/projects/drupal-x.y.z.tar.gz
     tar -zxvf drupal-x.y.z.tar.gz

   This creates a new directory drupal-x.y.z/ containing all Drupal files and
   directories. Copy the files into your Drupal installation directory:

     cp -R drupal-x.y.z/* drupal-x.y.z/.htaccess /path/to/your/installation

   If you do not have command line access to your server, download the archive
   from https://www.drupal.org using your web browser, extract it, and then use
   an FTP client to upload the files to your web root.

5. Re-apply any modifications to files such as .htaccess, composer.json, or
   robots.txt.

6. Run update.php by visiting http://www.example.com/update.php (replace
   www.example.com with your domain name). This will update the core database
   tables.

   If you are unable to access update.php do the following:

   - Open settings.php with a text editor.

   - Find the line that says:
     $settings['update_free_access'] = FALSE;

   - Change it into:
     $settings['update_free_access'] = TRUE;

   - Once the update is done, $settings['update_free_access'] must be reverted
     to FALSE.

7. Go to Administration > Reports > Status report. Verify that everything is
   working as expected.

8. Ensure that $settings['update_free_access'] is FALSE in settings.php.

9. Go to Administration > Configuration > Development > Maintenance mode.
   Disable the "Put site into maintenance mode" checkbox and save the
   configuration.

