Gateway with 2 ip#: resolve external dns name to internal ip in local network

[Kevin Darcy]

hbrucky wrote:

> hi,
>
> please have a look at this config and suggest your opinion:
>
> i've got a small lan with three pcs, one of them acting as a gateway to
> the internet (using nat) and as a local dns server (no dns queries from
> outside). it's equipped with two nics:
>
>         internet
>             |
>      +-eth1 / ppp0-+
>      |             |
>      |   gateway   |
>      |             |
>      +-----eth0----+
>             |
>       local network
>
> - eth0 to the local network with a fixed private ip# and dns name
> server.mylocaldomain
> - eth1 to the internet (using adsl) with dynamic ip# and external dns
> name resolved (externally) by dyndns.org
>
> the issue: when a host of the local network tries to resolve the external
> dns name of the gateway, it gets the external ip# of the gateway and
> therefore tries to connect the external nic of the gateway (which fails
> because of firewall rules).
>
> the question: is it possible to configure bind (v8 at the moment) on the
> gateway to resolve the external dns name of the gateway to its internal ip#?
> (the internal domain is not the same as the external domain)

You need "split DNS". Set up a "mirror" copy of your domain on your gateway
box, with all of the external addresses replaced with their internal
counterparts.


- Kevin