Hi people I am hoping someone can help with with a small problem I seem to be having with squid.

I run a linux gateway to the internet running squid (transparent proxy), dansguardian and gshield firewall.

OK, problem is the kids found out that if they entered no port numbers (ie blank) in the browser proxy settings they not only bypass dansguardian but direct connect to squid and can basically download to their hearts content ... well 1.1gb in just over an hour yesterday, to be exact. I dont have any filtering rules in squid, its a web-cache proxy and works with adzap to cull ad's on webpages - so anyone direct connecting has the world at their feet, so to speak.

Transparent proxy works and works well - there is no direct connection to the internet from the network at all.

I thought it might be some quirky thing with IE Explorer on their XP boxes, but alas, Opera 7.5 on my linux workstation does the same thing when you take out the port number and just leave in the IP of the squid box in the proxy settings.

I googled and googled until the fingers bled .... and couldn't find an acceptable answer. Some suggested that there is another proxy running on the machine ... nope, not that I can see, stopped apache just in case - but no wasn't that ... netstat didn't throw up any clues either.

I finally ended up setting up an acl in squid that stops my darling teenage sons getting access to the squid box without passing through dansguardian (which I use to block downloads mp3, avi etc - my RIAA MPAA insurance so to speak) - but this does not solve the mystery as to why they could connect to the proxy server in the first place without entering a port number in the browser settings.

I am just wondering if anyone has experienced this or knows anything about it ? and is prepared to shed a little light on the subect for me.

Thanks in advance.

PP