Syntax: client_max_body_size size;
Default:
client_max_body_size 1m;
Context: http, server, location
Sets the maximum allowed size of the client request body, specified in the “Content-Length” request header field. If the size in a request exceeds the configured value, the 413 (Request Entity Too Large) error is returned to the client. Please be aware that browsers cannot correctly display this error. Setting size to 0 disables checking of client request body size.
http://nginx.org/en/docs/http/ngx_http_core_module.html#client_max_body_size