"record has zero TTL" on resolving IN A

[Brian Salomaki]

On Wednesday 17 October 2001 02:38 pm, René Knudsen wrote:
> ... Removing  the comments didn't work :-((
>
> BUT, I found something very strange.....
> When resolving from my LAN-network to the nameservers
> local IP, the resolving works perfectly ....
>
> Example...
>
> Resolving: fj.b.dyndns.dk
>
> Answer using NS lan IP:  (10.0.0.2)
>             FJ.B.DYNDNS.DK      IN A      86400        80.62.189.193
>
> Answer using NS wan IP:  (212.242.188.77)
>             FJ.B.DYNDNS.DK      IN A              0         212.242.188.77
>
> Maybe a routing problem ???
> Router (Cisco) NAT from *.*.*.* > 10.0.0.2 port 53  TCP/UDP
>

Heh, most likely that's it.  Cisco's do very nasty (and unpredictable?) 
things to DNS packets when doing NAT.  We get this issue on the list a lot, 
but I've never seen a good solution other than to get rid of the Cisco router 
in that location, and replace it with a different NAT machine/router.

-- 
Brian Salomaki
Gambit Design Internet Services
110 E. State St., Suite 18, Kennett Square, PA 19348
DNSbox: http://gambitdesign.com