# 502 & 504 error, again **URL:** \ **Category:** NGINX\ **Created:** [January 2, 2012, 5:38am UTC](https://www.ruby-forum.com/t/502-504-error-again/215370 "2012-01-02T05:38:21Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![dubstep](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/cdc98d/32.png) [@dubstep](https://www.ruby-forum.com/u/dubstep)\ **Post date:** [January 2, 2012, 5:38am UTC](https://www.ruby-forum.com/t/502-504-error-again/215370/1 "2012-01-02T05:38:21Z")
I know it should be a well-known issue. I searched and try to find out what on earth it is, but I failed. Step: 1. nginx works as reverse proxy and the version is V1.0.5, OS: Debian 5.0.3, Kernel Version 2.6.32 2. Enabled http 1.1, 504 error is popup in client; the error log indicates: * * * ## 2011/12/30 09:40:06 [error] 11013#0: \*1 upstream timed out (110: Connection timed out) while reading response header from upstream, client: 10.208.127.142, server: 1.1.1.1, request: “POST /QueryStatManage/StatStudentAction.aspx HTTP/1.1”, upstream: " [http://1.1.1.1:80/QueryStatManage/StatStudentAction.aspx](http://1.1.1.1:80/QueryStatManage/StatStudentAction.aspx)", host: “1.1.1.1”, referrer: “[http://1.1.1.1/QueryStatManage/StatStudentAction.aspx](http://1.1.1.1/QueryStatManage/StatStudentAction.aspx)” 1. increase the vaule * * * 2011/12/30 09:53:54 [error] 11173#0: \*1 upstream prematurely closed connection while reading response header from upstream, client: 10.208.127.142, server: 1.1.1.1, request: “POST /QueryStatManage/StatStudentAction.aspx HTTP/1.1”, upstream: " [http://1.1.1.1:80/QueryStatManage/StatStudentAction.aspx](http://1.1.1.1:80/QueryStatManage/StatStudentAction.aspx)", host: “1.1.1.1”, referrer: “[http://1.1.1.1/QueryStatManage/StatStudentAction.aspx](http://1.1.1.1/QueryStatManage/StatStudentAction.aspx)” 1. Someone told me that there is a kernel bug in linux, I am not sure, can someone see the same issue ? thanks George ---
**Author:** ![Geoge.Q](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/e9c0ed/32.png) [@Geoge.Q](https://www.ruby-forum.com/u/Geoge.Q)\ **Post date:** [January 3, 2012, 12:55am UTC](https://www.ruby-forum.com/t/502-504-error-again/215370/2 "2012-01-03T00:55:05Z")
Hello! On Mon, Jan 02, 2012 at 12:37:36PM +0800, Geoge.Q wrote: > ## 2011/12/30 09:40:06 [error] 11013#0: \*1 upstream timed out (110: Connection timed out) while reading response header from upstream, client: 10.208.127.142, server: 1.1.1.1, request: “POST /QueryStatManage/StatStudentAction.aspx HTTP/1.1”, upstream: " [http://1.1.1.1:80/QueryStatManage/StatStudentAction.aspx](http://1.1.1.1:80/QueryStatManage/StatStudentAction.aspx)", host: “1.1.1.1”, referrer: “[http://1.1.1.1/QueryStatManage/StatStudentAction.aspx](http://1.1.1.1/QueryStatManage/StatStudentAction.aspx)” The “upstream” and “server” seems to be the same, so it looks like you’ve created an infinite proxy loop. Maxim D. ---
**Author:** ![Geoge.Q](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/e9c0ed/32.png) [@Geoge.Q](https://www.ruby-forum.com/u/Geoge.Q)\ **Post date:** [January 3, 2012, 1:38pm UTC](https://www.ruby-forum.com/t/502-504-error-again/215370/3 "2012-01-03T13:38:07Z")
thanks Max. I will check and update you. George ---
**Author:** ![Geoge.Q](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/e9c0ed/32.png) [@Geoge.Q](https://www.ruby-forum.com/u/Geoge.Q)\ **Post date:** [January 3, 2012, 3:45pm UTC](https://www.ruby-forum.com/t/502-504-error-again/215370/4 "2012-01-03T15:45:59Z")
On Sun, Jan 1, 2012 at 11:37 PM, Geoge.Q [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > I know it should be a well-known issue. > I searched and try to find out what on earth it is, but I failed. > > Step: > > 1. nginx works as reverse proxy and the version is V1.0.5, > OS: Debian 5.0.3, Kernel Version 2.6.32 > > 2. Enabled http 1.1, 504 error is popup in client; You enabled the HTTP/1.1 protocol? Where? What were you doing before? > ## the error log indicates: > > ## 2011/12/30 09:40:06 [error] 11013#0: \*1 upstream timed out (110: Connection timed out) while reading response header from upstream, client: 10.208.127.142, server: 1.1.1.1, request: “POST /QueryStatManage/StatStudentAction.aspx HTTP/1.1”, upstream: “[http://1.1.1.1:80/QueryStatManage/StatStudentAction.aspx](http://1.1.1.1:80/QueryStatManage/StatStudentAction.aspx)”, host: “1.1.1.1”, referrer: “[http://1.1.1.1/QueryStatManage/StatStudentAction.aspx](http://1.1.1.1/QueryStatManage/StatStudentAction.aspx)” How large is the POST? > /QueryStatManage/StatStudentAction.aspx HTTP/1.1", upstream: > “[http://1.1.1.1:80/QueryStatManage/StatStudentAction.aspx](http://1.1.1.1:80/QueryStatManage/StatStudentAction.aspx)”, host: “1.1.1.1”, > referrer: “[http://1.1.1.1/QueryStatManage/StatStudentAction.aspx](http://1.1.1.1/QueryStatManage/StatStudentAction.aspx)” Does the back end application work without nginx as proxy? What is the nginx configuration? We need details to help you. > 1. Someone told me that there is a kernel bug in linux, I am not sure, can > someone see the same issue ? Irrelevant. These are HTTP errors, with HTTP logging. If you have kernel errors, send your logs to the appropriate maintainers 🙂 You are running an [ASP.NET](http://ASP.NET) application. You have to correctly set proxy timeouts and buffer sizes to proxy to ASP applications, assuming the application works. Stefan C. > **[ScaleEngine is the Technical Video Streaming CDN Delivering Perfect Streams...](https://www.scaleengine.com/contact)** > > Video CDN, streaming live and on demand securely and reliably. Perfect streams to the world with our developer API, exact usage billing, and direct support