Nginx 反向代理上的连接被拒绝

Question

I have a server machine where I have configured a reverse proxy using Nginx. It is configured to cache the files it get from a CDN and server them. There is a firewall and a forward-proxy server configured in the network which the server belongs to. When I tried to connect to the server machine, it was returning 502. When I checked the nginx error logs, it was saying it could not connect to the upstream (which is the CDN). I want nginx to forward the request it gets, to the CDN through the forward-proxy(which is already configured in the network). What change do I need to make?

Here is my nginx.conf

worker_processes 1;
daemon on;
error_log /var/log/error.log;
pid /var/run/nginx.pid;
events
{
 worker_connections 1024;
}
http
{
 proxy_cache_path /path/to/the/cache/folder/1 levels=1:2 keys_zone=cache_common:512m max_size=128g inactive=7d use_temp_path=off;
 proxy_cache_path /path/to/the/cache/folder/2 levels=1 keys_zone=cache_version:1m max_size=128M inactive=60s use_temp_path=off;
 server
 {
 listen 8000 default;
 access_log /var/log/access.log;

 location /url1/ {
 proxy_cache cache_version;

 proxy_pass http://this-is-my-cdn-url.com; 
 }

 location /
 {
 proxy_cache cache_common;
 proxy_cache_use_stale error timeout http_500 http_502 http_503 http_504;
 proxy_cache_valid 404 1d;
 proxy_pass http://this-is-my-cdn-url.com;
 }
 }
}

Answer 1

I had got the solution to my issue. What I wanted to setup was an nginx reverse proxy, so that:

• it will receive requests from the client
• replace the host part in that URL with another CDN I wanted to access
• forward this request to the CDN, through a forward proxy.

I had to access the CDN through the nginx server, because I wanted to cache the contents served, and thus reduce the number of hits to CDN.

Well, the solution I got is this:

myconfig.conf

server {
listen 8000;
server_name my-domain-name.com;

location / {

rewrite ^(.*)$ "://the-cdn-domain-name.com$1";
rewrite ^(.*)$ "https$1" break;
proxy_pass http://X.X.X.X:1234; # this is my forward proxy IP
}
}

This is what you have to include in the conf.d directory. I have skipped the contents we have to give by default in nginx.conf