Internal and External DNS

Yan Seiner yan at
Tue Nov 30 13:45:45 UTC 1999

We're running someithing similar - we have an internal DNS and an
external DNS.  The external is maintained by our ISP; the internal is
purely internal.  The machines that are accessible from the inside and
outside have two interfaces, so have two different IP numbers (and

We have an internal bogus domain for which our internal name server is
authoritative; and forwards all other inquires to our ISP.

so a machine that is seen both from the inside and outside would be seen

Not quite the same names, but it gets around the mess of having two name
servers to maintain with similar, but slightly different, data.

We tried it the other way with all machines on the real domain, but the
coordination hassles outweighed the benefits of having a bogus domain
for our internal hosts.

Since all inquiries outside the bogus domain are forwarded to the
external name server, an internal user can still refer to
and have it resolved.


Kevin Darcy wrote:
> Shannon Rush wrote:
> > I would like to move my companies Internet DNS service in-house.  We have a
> > registered domain with a /26 public IP block.  We currently use the class A
> > network 10.x for our internal IP addressing, and have a firewall that does
> > NAT for all the addresses that need to be seen from outside our intranet.  I
> > need to find the most elegant way to set up my DNS servers for our public
> > and private networks.  I would like to use the same names in both our
> > private and public name space for the several machines that are publicly
> > accessible from the Internet.  Can this be done, and if so how?
> >
> > Shannon Rush
> > rushs at
> > Network Administrator
> > Lexicon

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"The older I get, the faster I was."

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