in /logs/access
there is always stored all access requests of website, i.e.
2017/02/03 17:51:22 HTTP 200 http://yoursite.com/url/ ............
2017/02/03 17:51:27 HTTP 200 http://yoursite.com/smth/ ............
and so on.
Does server also store $_POST data somewhere? at least, for the last day?