Nginx.conf

1) Add to /etc/nginx/nginx.conf

log_format timed_combined '$remote_addr - $remote_user [$time_local] '
    '"$request" $status $body_bytes_sent '
    '"$http_referer" "$http_user_agent" '
    '$request_time $upstream_response_time $pipe';

2) Modify access_log directive to use new format:

access_log /var/log/nginx/yourdomain.com.access.log timed_combined;