Internal server error, blank log file

I am running the latest version of NextCloud on an ubuntu vm, and this morning I find an internal server error:

Internal Server Error
The server encountered an internal error and was unable to complete your request.
Please contact the server administrator if this error reappears multiple times, please include the technical details below in your report.
More details can be found in the server log.

I suspect that something went sideways with a large upload using a sync client, but the nextcloud log file is blank so I can’t even verify it. What can be done at this point?


Check the webserver error.log for more information. If the webserver logfiles are empty, then the webserver can’t write (missing permissions, full quota, …), in doubt you could run the webserver in debug mode. But check the logfiles first…