[svlug] DNS behind a NAT firewall

[J C Lawrence]

On Mon, 02 Jul 2001 22:52:03 -0700 
Steve Hill <steveh at iname.com> wrote:

> I am running a multi-unit LAN behind a firewall, connected to a
> "single" static IP address issued by my DSL provider.  I am having
> a "thinko" trying to figure out how I can name a unit behind the
> firewall, such that it can be seen by the internet.  i.e., how do
> I get a name line system.dsl.com or how do I link my domainname to
> my IP address?  I don't need a cookie-cutter solution, but I need
> a couple of pointers that I can follow to solve my problem.

Briefly:

  You don't and you can't.  

DNS handles name<->IP mappings.  You only have one IP address
therefore all mappings share one end-point.  

  Caveat: You can do HTTP-based virtual hosting on multiple CNAMES
  or IN records assigned to the same IP.  

> Ultimately, I'd like to maintain my own mail and web servers
> behind the firewall.

Then just put port forwarding rules on your firewall such that port
80 on the firewall is forwarded to your web server and port 25 to
your mail server.

-- 
J C Lawrence                                             claw at kanga.nu
---------(*)                                http://www.kanga.nu/~claw/
I never claimed to be human.