DNS resolution and default SMTP route

[Barry Margolin]

In article <dqmf9q$22rf$1 at sf1.isc.org>,
 "et.favre at free.fr" <et.favre at free.fr> wrote:

> Hi,
> 
> I want to deploy a DNS solution using BIND on a private WAN network not
> connected to the Internet. The network is composed of several domains,
> but each domain can talk to each other only through specific and
> limited gateways (SMTP MTA, HTTP proxy ...).
> How could I configure BIND on a domain to resolve every SMTP domains of
> the zone with their real IP address, and for all other SMTP domains,
> the resolution should not give me the real IP address but the IP
> address of the gateway ?
> In other words, I would like the DNS to resolve every known name and to
> give me a default value if the name could not be resolved instead of an
> error message. And it's the gateway which will be able to forward the
> SMTP message either to the correct recipient, either to another gateway
> dependaing of the DNS resolution.
> I don't want to get the correct IP address from the first MTA because
> the topology of the network won't let me join the destination address.
> 
> Thanks for your responses.

Make your server authoritative for the root zone (named ".") and put a 
wildcard record that resolves to the address of the gateway:

* IN A <gateway>

The specific addresses of the other domains will override this default 
entry.

-- 
Barry Margolin, barmar at alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***
*** PLEASE don't copy me on replies, I'll read them in the group ***