Re: [squid-users] Re: Happy eyeballs and https

On 17/04/2014 2:30 a.m., Rob van der Putten wrote:
> Hi there
>
>
> Rob van der Putten wrote:
>
>> This morning my isp's tunnelserver (6in4) failed. This happened after
>> replacing a router. I don't know if this is an IPv4 router, IPv6 or both.
>> I couldn't ping the remote IPv6 address of the tunnel, or the IPv4
>> address of the tunnel server. Things returned to normal after they
>> rebooted the tunnel server.
>>
>> This is a log entry;
>> 1397639045.383 1940 pc6.ip6.sput.nl TCP_MISS/503 0 CONNECT
>> www.xs4all.nl:443 - HIER_NONE/- -
>>
>> My connect_timeout is 2 seconds which works fine for http. But https
>> pages just wouldn't load.
>
> Blocking IPv6 connections to port 443 in my firewall has exactly the
> same effect: The browser reports an error. There is no fallback to IPv4.
>

If you have time to dig into it the logics or CONNECT are in src/tunnel.cc.

NP: The peerSelect logics produce a list of potential destinations which
are supposed to be walked through and attempted until one succeeds.
Failure sent to the client only when there are none left to try or
connection timeout aborts the overall process.

For a cache.log trace of the tunnel operations use debug_options 26,4
Look for "comm failure recovery." for when failover is attempted.

HTH
Amos
Received on Wed Apr 16 2014 - 16:26:48 MDT