upload_max_file_size

The upload_max_file_size directive specifies the maximum size (in bytes) of a file that can be uploaded through the NGINX upload module. If a file exceeds this limit, a 413 (Payload Too Large) error response will be sent to the client instead of processing the upload. This directive is crucial for controlling resource usage and ensuring that your server can efficiently handle upload requests without being overwhelmed by excessively large files.

This directive can be defined at various contexts including http, server, location, if in location, and limit_except. The parameter for upload_max_file_size must be a single numerical value suffixed by a unit (k, m, g for kilobytes, megabytes, or gigabytes respectively). The configuration allows system administrators to set appropriate limits based on the server capacity and application requirements, providing a balance between usability and protection against unexpected resource consumption.

When uploading files, if the total size of the incoming request exceeds this limit, the module will abort processing the upload and return the specified HTTP error. It is advisable to set a reasonable limit based on your application's needs, as too high a limit may open up the server to excessive resource use, and too low may restrict legitimate use cases.