I am getting wrong response from nginx

[Maxim Dounin]

Hello!

On Tue, Apr 17, 2012 at 02:43:27PM +0300, Pekka.Panula at sofor.fi wrote:

> I am wondering how does nginx returns wrong content, atleast it seems so. 
> I am terminating https addresses to nginx thru my firewall, what does nat 
> public ips to nginx to ports 901 and 902 in this case, where nginx is 
> configured to wait https connections. 
> 
> So when end user hits eg address: https://a.host.com/, firewall does nat 
> and sends it to nginx private ip port 901, and https://b.host.com/ goes to 
> nginx private ip port 902. 

[...]

> server {
>    listen               81.x.y.x:901;

[...]

>    server_name  a.host.com atest.host.com;

[...]

>    location / {
>       proxy_cache off;
>       proxy_cache_valid 200 302 0;
>       proxy_cache_valid 301 0;
>       proxy_cache_valid any 0;
>       proxy_set_header ClientProtocol HTTPS;
>       proxy_set_header  Accept-Encoding  "";
>       proxy_pass http://1.1.1.131;

This will result in a request with "Host: 1.1.1.131" to a backend 
server, see http://nginx.org/r/proxy_set_header.

[...]

> server {
>    listen               81.x.y.x:902;

[...]

>    server_name  b.host.com btest.host.com;

[...]

>    location / {
>       proxy_cache off;
>       proxy_cache_valid 200 302 0;
>       proxy_cache_valid 301 0;
>       proxy_cache_valid any 0;
>       proxy_set_header ClientProtocol HTTPS;
>       proxy_set_header  Accept-Encoding  "";
>       proxy_pass http://1.1.1.131;

Same here.

[...]

> Now when i do go to address https://b.host.com/, i am getting response 
> from a.host.com.
> 
>  I am pretty if correct Host header goes to 1.1.1.131 server, it should 
> return different content, i have tested it manually using curl, eg:
> " curl --verbose --header 'Host: b.host.com' http://1.1.1.131" from nginx 
> machine, i will get correct content, but not thru nginx. 
> So i am assuming that somehow i am getting wrong content from a.host.com 
> or does nginx somehow leave Host header off? 

By default nginx uses the name you wrote in a proxy_pass directive 
for the Host header.  You probably want to use

    proxy_set_header Host $host;

or something similar in the locations above.

[...]

Maxim Dounin