I set up a Squid3 (Squid) proxy as part of my DansGuardian setup on Ubuntu to filter the kids’ web traffic. Â Overall, the proxy worked fine … but I was getting strange connection failures to some of the largest web properties, such as Yahoo, Google, YouTube and Facebook, whereas all smaller properties worked just fine.
The general error I was receiving was “The system returned: (110) Connection timed out”.
It turned out the problem was that Squid was using IPv6 to access any site that returned a legitimate IPv6 address. Â As my system wasn’t properly configured for IPv6, the request was failing.
The right answer, of course, is to get on board and configure properly for IPv6. Â It’s the future, it’s faster, etc.
The short answer is to add to your squid.conf file: Â dns_v4_first on
This will force Squid to check for a valid IPv4 DNS entry, and use that. Â fixed a day-long problem for me like … snap!