i have installed and configured squid 2.6.
i made the transparent proxy configuration:
"http_port 8080 transparent"
"always_direct allow all"
and set the route:
"iptables -t nat -A PREROUTING -i eth1 -p tcp --dport 80 -j REDIRECT --to-port 8080"

i put the ip of the lan interface of the server in the gateway of another machine, and the internet does not work until i set the proxy in the browser connection configuration.

then i installed firestarter and enable the sharing internet connection option and the internet works without the proxy configuration in the browser.

the question is:
how do i know if the clients having this server as their gateway are using the squid cache or going straight to the internet??

Thanks in Advance