Route external web to internal in DNS

[Gatt]

OK finally convinced our lot to use Joomla for our School Website

We're hosting it internally and publishing it via our ISA server.
At moment its via IP Address - Moorside High School

Now my query is this..

How do I translate the above IP (and eventually DNS Name) to our internal address ?

EG - internal user types in Moorside High School but is redirected to http://<internal-server-name>/joomla

At moment if they type the external IP nothing happens...

[srochford]

Do you have split DNS (ie different DNS servers for outside and inside)?

If so, you can set it so that (eg) OpenDNS resolves to 77.89.142.244 from outside but to the internal IP of your server.

At the moment, I'd guess that things are getting tangled because when the internal machines try and connect to that IP, it gets passed to the ISA server's internal address which then tries to fetch it via its external address. I don't know that you can't do that but it seems like it could get tied in knots :-)