DNS internal domain has same name as external website. How can I get to my external website from inside my network?

Thanks to: https://serverfault.com/q

Problem:

Our internal domain name is called "abc.com"  and our company website is called "abc.com".  I have created an "A" record that points to www.abc.com so staff can browse the website from within the office.  The problem is that if people enter "abc.com" from a web browser with the office it does not resolve in an efficient manner. 

Solution:

If you are running Exchange on the DC, do not set up a PortProxy - it may go without saying but it will break Exchange services hosted on port 80.

I realize this post is quite old, but you can still do this without installing IIS on the DC's. On every DC, run the following command to portproxy port 80 to the external web server.

netsh interface portproxy add v4tov4 listenport=80 listenaddress={Static IP v4 address of DC) connectport=80 connectaddress={IP Address of public Web Server}

Example:

netsh interface portproxy add v4tov4 listenport=80 listenaddress=DC1.abc.com connectport=80 connectaddress=www.abc.com

netsh interface portproxy add v4tov4 listenport=80 listenaddress=DC1.abc.com connectport=80 connectaddress=200.44.158.10

Show Results:

netsh interface portproxy show all

Delete Entry

netsh interface portproxy delete v4tov4 listenport=80 listenaddress=DC1.abc.com