We are uploading 10 files to our PHP frontend (4MB total) and Chrome always return "Connection closed" like the server dropped the http request. Of course we tried all the browsers and both Windows and Mac, we even tried with different ISPs, so we can exclude that the problem is client-side.
This happens only in the production environment, but we have a test environment which is identical (but in a different VM) and the problem doesn't appear in it (event using the same 10 files).
# php.ini max_execution_time = 30 max_input_time = 60 memory_limit = 128M max_file_uploads = 20 file_uploads = On post_max_size = 50M upload_max_filesize = 12M
We have tried even with bigger files and sometimes it works. But in some cases, with some files, it doesn't work (the files area essentially images and pdfs)
Looking at apache/php logs, there is no evidence that an error occurred, it seems that everything it fine. The access log shows POST /mypage 200
We already spent some good 12 hours on this weird issue, but still we can't figure out what's the problem.