title: How to config transparent proxy on openwrt
body: <p>I have a squid3 proxy server with 2 squid process running on dfferent port, as following:</p>
  
  <ul>
  <li>one squid running on "http_port 808"</li>
  <li>another running on "http_port 809 transparent" and has an iptable rule running as <code>iptables -t nat -A PREROUTING -i eth0 -p tcp  --dport 80 -j REDIRECT --to-ports 809</code></li>
  </ul>
  
  <p>I use proxy in 2 way:</p>
  
  <ol>
  <li>set proxy ip:808 into Internet Explorer option</li>
  <li>set proxy server as gateway in Windows network settings</li>
  </ol>
  
  <p>These 2 mode works well.</p>
  
  <p>Now I have a Linksys 1900AC router and have flashed openwrt 15.05. I want it to work as a transparent proxy so that every computer connected to this router could surf the Internet without setting Internet Explorer option.</p>
  
  <p>After some search, I found this <a href="https://wiki.openwrt.org/doc/uci/firewall#transparent_proxy_rule_external" rel="nofollow noreferrer">Wiki link</a>, but it doesn't  work. </p>
  
  <p>If I set <code>option dest_port  809</code>, my chrome browser shows "access denied" or something like that. If I set <code>option dest_port  808</code>, the squid "cuts off" my website URL.  Say that I enter <a href="http://www.bing.com/images" rel="nofollow noreferrer">http://www.bing.com/images</a>, squid just tells me that it "cannot find URL '/images'".</p>
  
  <p>Has anyone succeeded on this transparent proxy stuff?</p>