nginx.conf

```nginx
http {
  ...
  log_format  main '$remote_addr - $remote_user [$time_local] $status '
        '"$request" $body_bytes_sent "$http_referer" '
        '"$http_user_agent" "$http_x_forwarded_for" "$http_x_fasten_backend" "$ssl_client_s_dn"';

  log_format upstream_log '$remote_addr - $remote_user [$time_local] '
        '"$request" $status $body_bytes_sent '
        '"$http_referer" "$http_user_agent"'
        'rt=$request_time uct="$upstream_connect_time" uht="$upstream_header_time" urt="$upstream_response_time"';
...

upstream consul { server 127.0.0.1:8500; }

server {
  ...
  underscores_in_headers on;
  log_not_found on;
  access_log /var/log/nginx/access.log main;
  ...
  location @consul {
    access_log  /var/log/nginx/consul.log upstream_log;
    proxy_pass http://consul;
    ...
  }
}
```