I'm running some Rails servers behind unicorn, which is behind nginx.
I can see a handful of POST requests with a status of 408 in nginx's access.log
.
123.45.67.890 - - [17/Mar/2016:01:23:45 +1100] "POST /collections/ABC/items/DEFGH HTTP/1.1" 408 0 "http://catalog.paradisec.org.au/collections/ABC/items/DEFGH/edit" "MY FAVOURITE BROWSER"
But I can't see anything from the same time in unicorn.log
(which doesn't log an awful lot of stuff) or production.log
(which logs a fair amount of stuff).
Should Rails be logging anything in a HTTP 408 scenario?
production.log only logs requests which actually reach rails. It seems to me, that a 408 is caused by nginx. This can happen if your unicorn workers are busy. So in this case the request neither reached unicorn nor rails.