For a couple of days I've been getting 534 errors continually when trying to access /Site administration/Manage question types (i.e., ".../admin/qtypes.php"). I get the same error whether I attempt to open the page using my real IP address or a virtual private network address (set to the same country). It happens both with Chrome and with Firefox (both on Windows 10; I'll try a Linux machine later). If the error appears in, say, Chrome, I'll be locked out for 5 or so minutes but able to log in normally with Firefox and vice versa.
I presume this is a permissions error, but I am not sure how to fix it and what permissions I would need.
Environment:
- Moodle 4.0.4 (also happened with Moodle 4.0.3+)
- Nginx on Ubuntu 22.04 (on a VPS)
- Mariadb 10.6.7
- PHP 7.4.30