Hi Amos, thank you for the reply. I don't have IPV6 on my network and i've disabled CentOS IPv6 : cat /etc/sysconfig/network: NETWORKING_IPV6=no I'm using CentOS 5.8 and the last squid i can find using yum is this one i'm using: squid-3.1.0.16-7 - although yum (when trying to upgrade) says i've installed squid-2.6.STABLE21-6.el6. I'm going to further study and try to solve this issues with yum and squid. In my DNS (bind-9.3.6) i've disabled IPv6 name resolution... (i was getting a lot of errors in /var/log/messages). Can this have something to do? Should i enable IPv6 in bind ? Thank you Cheers, Bruno Santos ----- Original Message ----- From: "Amos Jeffries" <squid3@xxxxxxxxxxxxx> To: squid-users@xxxxxxxxxxxxxxx Sent: Saturday, 30 June, 2012 9:17:45 AM Subject: Re: TCP_MISS/503 0 CONNECT errors On 30/06/2012 1:30 a.m., Bruno Santos wrote: > Hi all. > > > I've search in the internet and i've done some experiences with some solutions i found on the internet, but still no luck. First hint: you are still using a *beta* release of Squid-3.1. That series has been in stable releases for over 2 years. NP: I advise using no release older than 3.1.15. There are major security vulnerabilities in all older releases. Second hint: that 503 status generated by Squid means no destination could be contacted. ie the TCP connection setup failed. "Error 111 (net::ERR_TUNNEL_CONNECTION_FAILED): Unknown error." is Chrome "user-friendly" display the 503 failure status. Guesses: DNS resolution of AAAA and A records failed (no destination able to be found). TCP connection to some found IPv6 address(es) failed TCP connection to some found IPv4 address(es) failed NP: the problem is very likely to be your IPv6 connectivity or some IPv6 issue in that 3.1 beta release. Google services are mostly IPv6-enabled and using HTTPS (via CONNECT) since earlier this month. Squid-3.1 will try very hard to connect using IPv6 whenever possible. Amos -- Use Open Source Software Human knowledge belongs to the world Bruno Santos bvsantos@xxxxxxxxxxxxxxxxxx http://www.twitter.com/feiticeir0 Tel: +351 962 753 053 Divisão de Informática informatica@xxxxxxxxxxxxxxxxxx Tel: +351 272 000 155 Fax: +351 272 000 257 Unidade Local de Saúde de Castelo Branco, E.P.E. geral@xxxxxxxxxxxxxxxxxx Tel: +351 272 000 272 Fax: +351 272 000 257 Linux registered user #349448 LPIC-1 Certification
