Part 1. Starting with the basics.... (it does get more complex, a lot more complex, I assure you). In this blogcast, you see an overview of the infrastructure and browse the "emulated" Internet using a client machine connected directly to the Internet. This client is move back to the corporate network and discover that Internet browsing no longer works. ISA Server monitoring is used to diagnose the cause, and find, at least in the first instance, that DNS queries to the Internet are failing. A new rule is created in ISA to allow these DNS queries to be made. Part 2 will solve Internet browsing....
Here's the network diagram as published in yesterday's post where you can also find out more about this blogcast series
If you're interested, here's the real quick and dirty ASP page I used for emulating microsoft.com
<%@ Language=VBScript %>
Demonstration INTERNET Web Site.<BR>
<I>(In reality, it exists on the Virtual Machine, "INET")</I><BR>
<B><font color=red size=4 face=arial>Welcome to Microsoft (www.microsoft.com)</B>
<% response.write "<BR>The time is " & now() & "<BR>" %>
<font face=arial size=4>
response.write "You requested this page from " & request.servervariables("REMOTE_ADDR") & "<BR>"
if request.servervariables("REMOTE_ADDR") <> "22.214.171.124" then
response.write "<BR>You are directly connected to the INTERNET"
response.write "<BR>You are connected to the Corporate LAN"