Re: [squid-users] Squid 3.1.12 - Parent Proxy and DNS queries

Amos Jeffries wrote:
> ...
> anything resolving to 127.0.0.1 on this host is not necessarily
> resolving to 127.0.0.1 on any other host (ie the parent proxy)
>
> NP: having a DNS server resolve 127.0.0.1 for anything public is very
> nasty.

Hi Amos,

Thank you for your help. Meanwhile i did some more testing and found
something strange. The test system cannot resolve any internet domains
itself so its nameserver uses a forwarder. If i silently drop the DNS
request packets through the packet filter, everything works fine. There
is no delay on any requests.
But, if i just remove the forwarder in DNS, so that every request for
external domains result in a NXDOMAIN DNS reply, a request takes about
90 seconds until it's finally processed.
The point i don't understand is, why Squid forwards the request without
any DNS reply but seems to do some timeout handling if NXDOMAIN is replied?
I also checked if there is any communcation between local squid and the
parent proxy but there isn't any in the latter test case.

Greetings,
Matthias
Received on Mon Sep 21 2009 - 08:49:39 MDT