Questions about proxy logging and a sanity check

[mike]

On 4/20/08, Igor Sysoev <is at rambler-co.ru> wrote:

> nginx tries them sequentially. As to 404, it seemd that you set
>
>     proxy_next_upstream  ...  http_404 ...;

Correct:

proxy_next_upstream error timeout http_500 http_503 http_404 invalid_header;

(I figure this will allow for any machines that are out of date,
throwing bad gateways, or anything else invalid to be passed on)

log_format proxy '[$time_local] $remote_addr - "$request" - $status -
"$upstream_addr" - "$upstream_response_time" - "$upstream_status"';

If I use this format, will the first server in $upstream_addr be the
one that actually replied? Is there any logic to it?

Thanks!