# 502 Bad Gateway when downloading file **URL:** \ **Category:** NGINX\ **Created:** [October 16, 2011, 1:52am UTC](https://www.ruby-forum.com/t/502-bad-gateway-when-downloading-file/212859 "2011-10-16T01:52:13Z")\ **Posts on this page:** 5\ **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:** [October 16, 2011, 1:52am UTC](https://www.ruby-forum.com/t/502-bad-gateway-when-downloading-file/212859/1 "2011-10-16T01:52:13Z")
Hello all. I have topology as follows: client-\>NGINX-\>haproxy-\> 4xapache servers. Problem is, that on one page, we have option to download file - it is done through changing header. Resulting header is as follows: Content-type: application/txt Content-Length: “xxxxx” Content-Disposition: attachment; filename=“aaa.txt” I’m getting 502 Bad Gateway, The server returned an invalid or incomplete response error everytime after clicking on link. In logs, there is nothing weird. When trying it directly through HAPROXY or directly through nginx (pointed to one of that apache servers) it is working correctly. Do you have any idea about how to resolve it? Have anybody experienced something like this? Many thanks for any reply concerning this. Posted at Nginx Forum: > **[502 Bad Gateway when downloading file](https://forum.nginx.org/read.php?2,216759,216759#msg-216759)** > > Hello all. I have topology as follows: client-\>NGINX-\>haproxy-\> 4xapache servers. Problem is, that on one page, we have option to download file - it is done through changing header. Resulting header is as follows: Content-type:... ---
**Author:** ![sogi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/838e76/32.png) [@sogi](https://www.ruby-forum.com/u/sogi)\ **Post date:** [October 16, 2011, 9:35am UTC](https://www.ruby-forum.com/t/502-bad-gateway-when-downloading-file/212859/2 "2011-10-16T09:35:43Z")
On Sat, Oct 15, 2011 at 7:51 PM, sogi [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Hello all. > I have topology as follows: > client-\>NGINX-\>haproxy-\> 4xapache servers. > > Problem is, that on one page, we have option to download file - it is > done through changing header. Resulting header is as follows: > Content-type: application/txt how do you change header, and can you please post complete headers from successful request[s] and from unsuccessful request? > Content-Length: “xxxxx” > > Content-Disposition: attachment; filename=“aaa.txt” > > I’m getting 502 Bad Gateway, The server returned an invalid or > incomplete response error everytime after clicking on link. In logs, > there is nothing weird. please post any relevant log entries When trying it directly through HAPROXY or > directly through nginx (pointed to one of that apache servers) it is > working correctly. we need to see the headers > Do you have any idea about how to resolve it? Have anybody experienced > something like this? > Many thanks for any reply concerning this. Stefan C. ---
**Author:** ![sogi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/838e76/32.png) [@sogi](https://www.ruby-forum.com/u/sogi)\ **Post date:** [October 16, 2011, 1:24pm UTC](https://www.ruby-forum.com/t/502-bad-gateway-when-downloading-file/212859/3 "2011-10-16T13:24:46Z")
Hello. Many thanks for your reply. We are changing headers through PHP header() function. Header is dispatching correctly from HAPROXY. It is as follows: HTTP/1.1 200 OK Date: Fri, 14 Oct 2011 01:18:08 GMT Server: Apache/2.2.16 (Debian) X-Powered-By: PHP/5.2.10 Expires: Thu, 19 Nov 1981 08:52:00 GMT Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0 Pragma: no-cache Content-Length: 77032; Content-Disposition: attachment; filename=“aaaa.txt” Connection: close Content-Type: application/txt Logs from nginx debug: [http://pastebin.com/UrMXgYyf](http://pastebin.com/UrMXgYyf) (I have more - all from logging into system to 502, but there are so large actually 🙂 ) Actually, I don’t have any successful header… Let me know if you want something, I can debug/prepare it if you need more informations. Many thanks for all the help. Posted at Nginx Forum: > **[Re: 502 Bad Gateway when downloading file](https://forum.nginx.org/read.php?2,216759,216774#msg-216774)** > > Hello all. I have topology as follows: client-\>NGINX-\>haproxy-\> 4xapache servers. Problem is, that on one page, we have option to download file - it is done through changing header. Resulting header is as follows: Content-type:... ---
**Author:** ![sogi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/838e76/32.png) [@sogi](https://www.ruby-forum.com/u/sogi)\ **Post date:** [October 16, 2011, 4:15pm UTC](https://www.ruby-forum.com/t/502-bad-gateway-when-downloading-file/212859/4 "2011-10-16T16:15:42Z")
mmm you are the man 🙂 Well, its confirmed now - it is working when I removed ; from header. I missed it before… Great - many thanks again - you made my day 🙂 Posted at Nginx Forum: > **[Re: 502 Bad Gateway when downloading file](https://forum.nginx.org/read.php?2,216759,216779#msg-216779)** > > Hello all. I have topology as follows: client-\>NGINX-\>haproxy-\> 4xapache servers. Problem is, that on one page, we have option to download file - it is done through changing header. Resulting header is as follows: Content-type:... ---
**Author:** ![sogi](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/838e76/32.png) [@sogi](https://www.ruby-forum.com/u/sogi)\ **Post date:** [October 16, 2011, 2:31pm UTC](https://www.ruby-forum.com/t/502-bad-gateway-when-downloading-file/212859/5 "2011-10-16T14:31:58Z")
Hello! On Sun, Oct 16, 2011 at 07:24:34AM -0400, sogi wrote: > pre-check=0 > > Pragma: no-cache > > Content-Length: 77032; The “;” is incorrect and shouldn’t be here. If it’s indeed present in headers returned by your backend - there is no surprise haproxy rejects such responses (see below). > Logs from nginx debug: > [http://pastebin.com/UrMXgYyf](http://pastebin.com/UrMXgYyf) > (I have more - all from logging into system to 502, but there are so > large actually 🙂 ) Debug log shows response from backend was already 502: 2011/10/13 21:47:05 [debug] 15881#0: \*33 http proxy status 502 “502 Bad Gateway” That is, most likely it’s haproxy who returned 502. See above for possible reason. Maxim D.