nginx log http status what is 404 187

Question

Hi I got nginx access log file like the follows:

192.168.1.1 - - [06/Nov/2012:22:13:46 +1100] "GET /?i=a HTTP/1.1" 404 187 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:14.0) Gecko/20100101 Firefox/14.0.1"
192.168.1.2 - - [06/Nov/2012:22:13:50 +1100] "GET /?i=b HTTP/1.1" 200 0 "http://abc.com/545512565475443/" "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.4 (KHTML, like Gecko) Chrome/22.0.1229.94 Safari/537.4"

So that 404 in the first line should be not found and 200 in the second line means success. That's okay, but what is the 187 behind 404 in the first line and 0 behind 200 in the second line?

thanks, Green

Answer 1

according to this default log format is:

log_format combined '$remote_addr - $remote_user [$time_local]  '
                    '"$request" $status $body_bytes_sent '
                    '"$http_referer" "$http_user_agent"';

so 187 or 0 after the response code is number of bytes sent to client