I am attempting to upgrade my Drupal 8.9.2 multi-site installation to D9. I was hoping to work this all out on a development installation, that is located in a subdirectory of my home directory on my NameCheap Shared Hosting plan.
When I first installed this installation, I did so using the tarball method from years ago. I then followed the instructions given here (https://www.drupal.org/docs/installing-drupal/add-composer-to-an-existing-site). I was able to get the current running prod version converted to use composer with out an issue.
Before I go and start messing with the files, and attempting to upgrade to D9 through composer on a prod installation, I wanted to copy these files over to another installation where I can use it as a sandbox. To do this I:
- copied the files on my server to a new directory
- made clone databases for the new installation
- truncated all the cache tables in the cloned DB
- changed all the database settings in the settings files to point to the cloned databases
I've done this before without any issues, and now I seem to be getting a WSOD error on all the sites running from the new installation. The error I'm getting is
PHP Fatal error: Uncaught Error: Class 'Drupal\Core\Cache\DatabaseBackend' not found in ~/{new installation dir}/public_html/index.php:16.
If anyone has any thoughts what's going on I am all ears.
Thank you in advance