How to Stop bypassing Proxy server?

i am using a similar setup on my network. what i did was this. (squid is
using port 3128).

1) created a bridge with 2 network cards.
2) configured the router to pass all traffic to this proxy
3) iptables -t nat -A PREROUTING -p tcp --dport 80 -j REDIRECT --to-port
3128.
4) configured squid to do transparent proxy.

All the users dont even know they are behind the squid proxy.

Andrew

"ssp2000" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> Some of the users at my location are accessing the Internet by
> bypassing the in-house proxy server. They are just typing the upstream
> proxy server IP address and port number in browser and accessing the
> Internet. How can I prohibit such activities? My network is on
> 192.168.7.0 and IP address of upstream proxy server is 195.2.104.7
> (take these IP addresses as an example). I can access 195.2.104.0
> network from my location. I am using Squid Proxy server on Linux
> RH8.Can anyone suggests use of IPTABLES to achieve this?

Some of the users at my location are accessing the Internet by
bypassing the in-house proxy server. They are just typing the upstream
proxy server IP address and port number in browser and accessing the
Internet. How can I prohibit such activities? My network is on
192.168.7.0 and IP address of upstream proxy server is 195.2.104.7
(take these IP addresses as an example). I can access 195.2.104.0
network from my location. I am using Squid Proxy server on Linux
RH8.Can anyone suggests use of IPTABLES to achieve this?

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In comp.os.linux.networking ssp2000 <(E-Mail Removed)> suggested:
> Some of the users at my location are accessing the Internet by
> bypassing the in-house proxy server. They are just typing the upstream
> proxy server IP address and port number in browser and accessing the
> Internet. How can I prohibit such activities? My network is on
> 192.168.7.0 and IP address of upstream proxy server is 195.2.104.7
> (take these IP addresses as an example). I can access 195.2.104.0
> network from my location. I am using Squid Proxy server on Linux
> RH8.Can anyone suggests use of IPTABLES to achieve this?

Sounds like FAQ:

[http://www.squid-cache.org/Doc/FAQ/FAQ.html]

17. Interception Caching/Proxying

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Michael Heiming (GPG-Key ID: 0xEDD27B94)
mail: echo (E-Mail Removed) | perl -pe 'y/a-z/n-za-m/'
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