Nginx two servers were invoked when processing 1 request
<p>Seeing this in nginx logs:</p>

<pre><code>"upstream": "52.86.112.192:443, 52.86.78.197:443",
"upstream_response_time": "7.005, 7.016",
</code></pre>

<p>The documentation of nginx says:</p>

<pre><code>If several servers were contacted during request processing, 
their addresses are separated by commas, 
e.g. “192.168.1.1:80, 192.168.1.2:80, unix:/tmp/sock”.
</code></pre>

<p>Unfortunately it is not clear to me how can two servers be invoked when processing 1 request? This is w/o internal redirects? Was it a retry after the first attempt failed?</p>

<p>The DNS query returns two A records:</p>

<pre><code>xxx.us-east-1.elb.amazonaws.com. 60 IN A 54.84.139.107
xxx.us-east-1.elb.amazonaws.com. 60 IN A 52.71.207.21
</code></pre>

<p>Does it mean, than nginx does a retry for every failed request automatically? Or can it be configured? (this is AWS so the IP's of the load balancers are changing constantly)</p>