DNS server configuration Options

[linuxuser1]

Hi,

I'm using a DNS server under linux i.e. BIND 9.5.1-P2 and I'd like to configure it with the following manner :
-When a DNS request is received, it shall reply the sender with information located in internal zone file (which is OK for me) but also forward the same query outside the machine to ISP DNS servers (configured in forwarder clause).
The result is to have 2 different replies for the same request : 1reply from my local DNS server and the second one from the ISP DNS server.

The current behavior of my setup now : my DNS server always reply suing its own zone files and doesn't forward DNS query outside.

Could anyone please help me on this topic?

Thanks in advance