Timeout on DNS Request with Bind

[Olivier BONHOMME]

Hello,

I am writing here because I have a strange problem with a BIND 9.2.4
installed on a Sarge Box. In my previous LAN architecture, this box was
directely connected to internet via a PPPoE connection. In that
configuration, there was no problem : The BIND resolved quickly the
requests.

Then I changed my architecture and installed a Speedtouch Router between
the Debian and the Internet and since this moment some outgoing requests
 time out.

Here is an example :

C:\Documents and Settings\ptitoliv>nslookup
Serveur par dÚfaut :  gatekeeper.ptitoliv.lan
Address:  192.168.1.2

> host google.com
DNS request timed out.
    timeout was 2 seconds.
DNS request timed out.
    timeout was 2 seconds.
*** Impossible de trouver l'adresse pour le serveur google.com : Timed out
> host google.com
Serveur :  google.com
Addresses:  64.233.187.99, 72.14.207.99, 64.233.167.99
>

I tried to tcpdump and I saw that my bind server wait a little moment
before connecting to the root servers in order to make the resolution.

So in a temporary way, I put my ISP Dns as a forwarder and in that case,
I have no time out problem.

Does anybody knows why bind can have this behaviour ?

Thanks for your answers

Regards,
Olivier BONHOMME