Redirection of web content from linux router to separate web proxy

Question

Here's a good one: while I like the reporting features and https filtering of the up-and-coming Sphirewall firewall/router distribution, it is not quite up to speed on the things that I require in order to run it as the default gateway on my networks (notably Strongswan VPN and 64 bit support). However, if I configure it as a standalone server that isn't the default gateway, then I must use a proxy server config on each PC, phone, tablet or toaster, as I understand. I don't use Cisco so I don't have WCCP available but, assuming that my default gateway was just linux, would it be possible to transparently redirect web traffic through the sphirewall proxy such that I do not have to configure proxy servers on my devices?

Answer 1

There are several possible approaches to this which are best used combined:

• announce the proxy presence via WPAD - http://en.wikipedia.org/wiki/Web_Proxy_Autodiscovery_Protocol , http://techlib.barracuda.com/display/WSFLEXV41/How+to+Configure+Proxy+Settings+Using+PAC+Files+and+WPAD
• configure the so called transparent proxy - http://www.cyberciti.biz/tips/linux-setup-transparent-proxy-squid-howto.html

This approach helps with the fact that most clients will autodiscover the proxy via the WPAD mechanism and use your configuration. For the rest they will be transparently natted to the proxy and their traffic handled