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Re: Strange dns results from dig +trace

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On 17.09.2011 08:29, David W. Hodgins wrote:
> 
> Regardless of what I have installed, shouldn't dig +trace show what
> the actual nameserver is showing?
> 
> What do you see for the A record from "dig +trace hodgins.homeip.net".

I know that some routers, in particular the Cisco firewalls, mangle DNS
resposes that resolve to an external IP address on which port forwarding
is performed, and replaces the address with the local NATed IP address
to avoid hairpin NAT issues.

From where I sit, hodgins.homeip.net seems to resolve properly to a
public IP address:

hodgins.homeip.net.     60      IN      A       216.240.4.31
homeip.net.             86400   IN      NS      ns1.dyndns.org.
homeip.net.             86400   IN      NS      ns2.dyndns.org.
homeip.net.             86400   IN      NS      ns3.dyndns.org.
homeip.net.             86400   IN      NS      ns5.dyndns.org.
homeip.net.             86400   IN      NS      ns4.dyndns.org.
;; Received 372 bytes from 2600:2003::75#53(ns3.dyndns.org) in 206 ms

I strongly suspect this is caused by a meddling DNS proxy service in
your router. What does tcpdump show if you do "nslookup -q=a
hodgins.homeip.net 8.8.8.8" or similar? Can you temporarily disconnect
the router and try dig/nslookup/host while directly connected to the
ADSL modem?

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Thread

Strange dns results from dig +trace "David W. Hodgins" <dwhodgins@nomail.afraid.org> - 2011-09-16 18:37 -0400
  Re: Strange dns results from dig +trace KR <kristian.rasmussen@broadpark.no.spam.com> - 2011-09-17 01:24 +0200
    Re: Strange dns results from dig +trace "David W. Hodgins" <dwhodgins@nomail.afraid.org> - 2011-09-17 02:29 -0400
      Re: Strange dns results from dig +trace KR <kristian.rasmussen@broadpark.no.spam.com> - 2011-09-17 13:28 +0200
        Re: Strange dns results from dig +trace "David W. Hodgins" <dwhodgins@nomail.afraid.org> - 2011-09-17 18:33 -0400
      Re: Strange dns results from dig +trace GangGreene <GangGreene@invalid.com> - 2011-09-17 07:40 -0400

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