Can I log HTTP 400s to a different log file instead of my default access logs

[António P. P. Almeida]

On 7 Nov 2011 11h21 WET, nginx-forum at nginx.us wrote:

> Hello
>
> I'd like to know if its possible for me to log HTTP 400 errors to a
> different log file. Right now they go in the access log. 
>
> To give some background, we've got this problem where if a single
> resource is requested from chrome, after the resource request is
> served, a http 400 error is logged in the access logs. This I've
> understood to be is due to the nature of connections opened by
> Chrome (2 for every request) and one of the connections not been
> used before its closed. And nginx reports a 400 in this
> instance. I've gathered this based on a different forum entry. And
> when this 400 is logged, the $request_filename is /etc/nginx//html

Try (untested):

at the http level:

map $request_filename $is_400 {
   default 0;
   /etc/nginx/html 1; 
}

on the vhost config:

error_page 400 @log-400;

location @log-400 {

   access_log /path/to/400.log;

}

Caveat emptor: I've never played with the access_log directive that
much. 

--- appa