NGINX: upstream timed out (110: Connection timed out) while reading response header from upstream

Question

I have Puma running as the upstream app server and Riak as my background db cluster. When I send a request that map-reduces a chunk of data for about 25K users and returns i

Answer 1

In your case it helps a little optimization in proxy, or you can use "# time out settings"

location / 
{        

  # time out settings
  proxy_connect_timeout 159s;
  proxy_send_timeout   600;
  proxy_read_timeout   600;
  proxy_buffer_size    64k;
  proxy_buffers     16 32k;
  proxy_busy_buffers_size 64k;
  proxy_temp_file_write_size 64k;
  proxy_pass_header Set-Cookie;
  proxy_redirect     off;
  proxy_hide_header  Vary;
  proxy_set_header   Accept-Encoding '';
  proxy_ignore_headers Cache-Control Expires;
  proxy_set_header   Referer $http_referer;
  proxy_set_header   Host   $host;
  proxy_set_header   Cookie $http_cookie;
  proxy_set_header   X-Real-IP  $remote_addr;
  proxy_set_header X-Forwarded-Host $host;
  proxy_set_header X-Forwarded-Server $host;
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}

Answer 2

As many others have pointed out here, increasing the timeout settings for NGINX can solve your issue.

However, increasing your timeout settings might not be as straightforward as many of these answers suggest. I myself faced this issue and tried to change my timeout settings in the /etc/nginx/nginx.conf file, as almost everyone in these threads suggest. This did not help me a single bit; there was no apparent change in NGINX' timeout settings. Now, many hours later, I finally managed to fix this problem.

The solution lies in this forum thread, and what it says is that you should put your timeout settings in /etc/nginx/conf.d/timeout.conf (and if this file doesn't exist, you should create it). I used the same settings as suggested in the thread:

proxy_connect_timeout 600;
proxy_send_timeout 600;
proxy_read_timeout 600;
send_timeout 600;

Answer 3

I had the same problem and resulted that was an "every day" error in the rails controller. I don't know why, but on production, puma runs the error again and again causing the message:

upstream timed out (110: Connection timed out) while reading response header from upstream

Probably because Nginx tries to get the data from puma again and again.The funny thing is that the error caused the timeout message even if I'm calling a different action in the controller, so, a single typo blocks all the app.

Check your log/puma.stderr.log file to see if that is the situation.

Answer 4

From our side it was using spdy with proxy cache. When the cache expires we get this error till the cache has been updated.

Answer 5

I would recommend to look at the error_logs, specifically at the upstream part where it shows specific upstream that is timing out.

Then based on that you can adjust proxy_read_timeout, fastcgi_read_timeout or uwsgi_read_timeout.

Also make sure your config is loaded.

More details here Nginx upstream timed out (why and how to fix)