I have a CentOS 6 box running Squid and Privoxy to create a custom proxy setup. The server has several public IPv4 addresses configured on virtual eth0 interfaces.

My Goal:

I want to send all proxy traffic through a specific IPv4 address that is setup on the server, but is not the default IP.


All proxy traffic is being sent through the default IP of the eth0 interface. I don't want this IP to be used.


I am using both Squid and Privoxy in my proxy.


My squid install is configured on an external IPv4 address http_port x.x.x.x:8080and is what a client uses to connect to the proxy.

Squid is using cache_peer to connect to a local Privoxy server running on the same server.


Privoxy is setup as local only and has a listen-address of [::1]:8118 and (localhost only). Privoxy does further filtering, that Squid otherwise cannot do.

Privoxy does not do any additional forwarding but filters and modifies header information.

What I've tried:

I tried using tcp_outgoing_address x.x.x.x in Squid, however this causes a "Zero Sized Reply" error when applied in the config. This is because of Privoxy being involved in the chain. If I removed Privoxy from the chain it works. Similarly I used POSTROUTING with iptables and got the same error trying to change the source IP.

I would like assistance in finding a working solution to get my proxy traffic routed through a user specified IPv4 address, with Squid and Privoxy connected together. I am open to any setup changes required for this to work.


  • I found my proxy chain is the issue. I have added more information and revised my original question. – James White Jun 15 '15 at 20:18

I decided that Privoxy was the main issue and decided to use SquidGuard instead, by removing Privoxy from the chain I was able to use tcp_outgoing_address as required.

|improve this answer|||||

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.