squid3 is denying all http sites
 

Hi All,
I had set up trasparent squid proxy using Ubuntu. Everything was working fine but suddenly everyone is getting access deny error since yesterday even I have neither done any changes in squid.conf file nor updated anything and nor blocked any sites. And also replaced squid.conf file from backup which was older than couple of weeks back but still everyone is denying for all http sites including me. But no problem for https and mails, so problem may be from squid. I stoped, started, restarted, reloaded squid service with no errors, though the problem couldn't get rid. I couldn't not find out the reasons why. So begging your kind help in this. Right now I have removed the entry which was redirecting http request to squid port 3128 in PREROUTING table of NAT to be working as only router and could solved http issues. So should I uninstall and reinstall squid3 again?
I am stuck for what next? so please help.

Thanks in advance for your kind help.

Hi post:

Your squid.conf

Your Iptables rules:

We cannot be of any help unless you give us more to work with.

Sorry, that's wrong. If everything was working fine, then it STOPPED working, then SOMETHING CHANGED. If you didn't change it, someone else did.
Then you can determine from those symptoms that port 80 is somehow getting blocked. Have you checked port 80? Any firewall/router/switch updates further upstream? Have you looked at iptables on that system?
Well, have you LOOKED for any reasons?? If all you did was stop/restart the service, that's nothing in the way of looking for a problem. Start with doing basic diagnostics. If you disable squid, can you then get out to the Internet? Have you checked any log files? Gotten with your networking folks to see what (if anything) has changed? Have them help you trace the traffic? [/QUOTE]
Why would removing the redirect rule for http make it work, when it WAS working with the rule in place before??? All signs point to SOMETHING changing. Again, basic diagnostics and thought about the problem will give you clues. If you KNOW nothing changed on your proxy server (meaning Ubuntu updates, squid changes or network changes), then the problem is very obviously further upstream in your network.
Why would re-installing something you've already got working make things better?? It'll use the same configuration as before, and STILL not work.

Thanks for the reply gdizzle and TB0ne Guru.
Your explanations are obsolutely right. But I can't troubleshoot live by disturbing the users for http sites, so first I need to take the proxy server offline by providing direct internet access to the users and then I can troubleshoot it. So waiting for that time when my seniors says. Though I will be following the ways whichever you have explained and come back with as what was the problem if I could fixed it or come back even if I can't.

Once again thanks for your kind guidance.

Thanks TB0ne Guru.
You are absolutely right, the problem was not in the squid.conf file instead in another file(wrong ACL entry) which was defined in the ACL list in squid.conf file.

Thanks a lot.