Upstream Keepalive connection close

[Maxim Dounin]

Hello!

On Tue, Jan 06, 2015 at 06:06:18AM -0500, Gona wrote:

> I have Nginx server configured with couple of backend servers with keepalive
> connections enabled.
> 
> I am trying to understand what will be the Nginx's behaviour in case the
> connection is closed by an upstream server legitimately when Nginx is trying
> to send a new request exactly at the same time. In this race condition, does
> Nginx re-try the request internally or does it return an error code?
> 
> In case Nginx needs to be forced to retry, should I be using
> proxy_next_upstream? My understanding is that this setting will make the
> request re-tried on the next server in the upstream block. On the same note,
> how do I force the retry on the failed server first to avoid cache misses.

As of now, nginx will only retry the request to the next server, if 
any (as soon as "proxy_next_upstream" includes "error", which is 
the default).

-- 
Maxim Dounin
http://nginx.org/