What is the difference between a forward agent and a reverse proxy

The concept of forward agent

The forward agent, the legendary agent, works like a springboard,

To put it simply,

I'm a user, I can't access a website, but I can access a proxy server

This proxy server, he can access the site that I can not access

So I first connected to the proxy server and told him that I needed the content that could not access the site

Proxy server to fetch it back and then return to me

From the point of view of the website, there is only one record when the proxy server comes to fetch the content

Sometimes do not know is the user's request, also hides the user's information, depending on the agent does not tell the website

The conclusion is that the forward proxy is a server between the client and the original server (Origin server), in order to get content from the original server, the client sends a request to the agent and specifies the target (the original server), and then the agent forwards the request to the original server and returns the contents to the client. The client must make some special settings to use the forward proxy.

Enable Apache proxy module

A2enmod Proxy  
A2enmod proxy_http

Configuring forward proxies is simple, just add your Apache-configured Vhost host to the browser's proxy option

1.1 Apache Configuration httpd-vhosts.conf (for example, under Windows)

<virtualhost *:80>  
    ServerAdmin prograsliu@gmail.com  
    documentroot "D:/www/test"  
    ServerName www.test.com  
    serveralias test.com  
    ErrorLog "Logs/test.com-error.log"  
    Customlog Test.com-access.log "Common      
    alias/sublook" d:/www/test/look/sublook/  
    <directory "D:/www/test" >  
        Options followsymlinks  
        allowoverride all order  
        allow,deny  
        allow  
    </Directory>  
          
    #正向代理设置  
    Proxyrequests on  
    Proxyvia on  
      
    <proxy *> order  
        Deny,allow  
        deny to all  
        allow from 127.0.0.1  
    </Proxy>  
</VirtualHost>

Now look forward to the proxy set that section

Proxyrequests on: Open Apache forward Proxy

Proxyvia on: Controls the flow of proxy requests that reside in the chain of proxy servers

References to Proxyvia in the official Apache2.2 document are as follows:

1. If set to the default value off, special handling will not be taken. If a request or answer contains a "via:" header, it will be passed without any modification.

2. If set to on each request and answer will get a "Via:" header on the former host.

3. If set to full, each generated "via:" header will be added to the Apache server version, the "via:" annotation field appears.

4. If set to block, all the "Via:" header lines in each agent request will be deleted. and will not produce a new "Via:" header.

<proxy *>...</proxy>: To control who can access your agent

<proxy *> order  
     Deny,allow  
    deny to all  
     allow from 127.0.0.1  
</Proxy>

This is set to this machine can use the agent, when the real use of the set up their own

1.2 Browser settings (for example, Firefox)