DNS is working but unresolved DNS issue remains

Question

Perhaps someone can help me with a DNS issue.
I have DNS working fine on a my Mac server.
I take responsibility for the domain (example.com) and establish the primary zone with the nameserver as server.example.com.
I also setup a A record for the phrase www.example.com to point to the externally hosted website.
That all works fine inside the network.
sudo changeip -checkhostname resolves just fine.
The problem is that I need to establish a reference for a test website : www.example.com/wp-admin so that it works inside the network.
That URL has a different IP address than the www record.
A) I'm not sure how to add the part of the URL past example.com
B) I cannot add a / as part of the machine name - the server software forbids it.
Can anyone clue me into how to do this?

Answer 1

DNS is not the tool you need here.
DNS translates host names and (for some protocols) IP ports, but doesn't translate file paths.
In the classic URL scheme (and simplifying things), the DNS translation deals with getting an IP host address for the string that's between the first double // and the subsequent / in the URL, and nothing else.
To differentiate further, you can either use a virtual host (what Apple calls a "Site" in Server Admin) on the target server, or can configure the web server (usually via a rewrite rule) to redirect the incoming HTTP request to the path you want.
Depending on exactly what you're up to here, sometimes a reverse web proxy can be used. A reverse web proxy is where you're forwarding an incoming HTTP request from one server along to another web server, either on the same or another IP host.
[Here|http://labs.hoffmanlabs.com/node/1329] is a write-up on virtual hosts on Mac OS X Server.