Documentation Level: 
Intermediate
Documentation Status: 
No known problems

Minor and patch updates are straightforward and usually may be done independently of any module updates. It's usually a good idea to update Backdrop CMS core independently, before attempting any module updates. You can update Backdrop CMS core code via the administrative interface or directly if you have FTP access to your hosting service; both are described below.

Preliminaries: Make a Backup

  1. Make a backup of your database.
  2. Make a backup of the active config directory (located at files/config_[hash]/active unless otherwise specified in the settings.php file).
  3. Login to your site as a user with the "Administrator" role.
  4. Put your site into maintenance mode (optional, but strongly recommended) at /admin/config/development/maintenance (Configuration > Development > Maintenance mode).

Check for Updates

  1. Go to the list of available updates at /admin/reports/updates/list. If a Backdrop CMS update is available, it will be listed there as the first item on the list.
  2. Check the Release notes for anything to be aware of. There will be a link in the table under "Recommended Version".
    • Note: If any of the files outside the core directory have been changed and need to also be updated, they will be explicitly mentioned in the release notes. These will not be changed by the System Updater (to avoid overwriting any changes you have made) and may need manually updating; there will be instructions in the release notes.

Update Core Code

The Project Installer module can be used to update the code from within the Backdrop CMS admin interface. If you would prefer not to enable the installer module enabled on a production site, another option would be update the code via FTP. You can download the latest Backdrop CMS code using the Download link on backdropcms.org, and replace the corresponding files at your site's host (assuming you have FTP access to your site).

Updating Core Code via the Adminstrative Interface

To update the core code using the System Updater in the administrative area of the website, you will have to have the Project Installer module enabled on your site:

  1. Navigate to /admin/modules/list (Functionality > List modules) and look for the Project Installer module; if it is not checked, check its box and then click "Save Configuration." If it is already checked, proceed.
  2. Navigate to the System Updates page. This can be accessed in a few different ways:
    • Go from the list of Available updates at /admin/reports/updates/list following the "Install system updates" link at the top.
    • Navigate directly to the page using the URL (admin/config/system/updates) or the Admin menu (Configuration > System > System updates)
    • Follow the link in the Status report under Backdrop CMS update status.
    • If the "Install system updates" link is missing, you should check permissions for the Project Installer module.
  3. Select "Backdrop" to update core, click "Download Selected Updates" and the updater will download the new version and take you to the "Ready to update" page.
  4. If you haven't already put the site into maintenance mode you should check the box to put it into maintenance mode for this next step.
  5. Click 'Continue' and the update will be applied.
  6. There will be a link to "Run site updates"; follow that link. You can also access that page by going to core/update.php (e.g. https://example.com/core/update.php).

Updating Core Code Directly

To update core code directly, e.g., by uploading files via FTP, do the following:

  1. Download the core code using the Download link for Backdrop CMS and expand the .zip file.
  2. Upload the "core" directory from your download to replace the corresponding "core" directory in your site files.
  3. If the release notes noted changes in the .htaccess or robots.txt file, replace those files in your site files with the new ones. If you have modified those files, you will have to merge the changes into your modified files.
  4. Go to the "Backdrop Site Update" page at /core/update.php

Running Site Updates

After updating core code via either method, continue as follows (you will be on the "Run site updates" page at /core/update.php):

  1. After checking that you are happy with all your backups, click Continue.
  2. If any errors have appeared, these will need to be addressed and you may need to run the update again. Help is available in the Forum or the chat channel.
  3. If no errors are shown then everything has been updated successfully.
  4. If you turned on the maintenance mode option, turn it back off at /admin/config/development/maintenance (Configuration > Development > Maintenance mode) to make your site publicly accessible again.

If you used the administrative interface to update core code, you may disable and, if you wish, uninstall the Project Installer module, or you can leave it in place for the next time you update core code.