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Yes thank you. But...
I guess the question should have been: How do you configure two HFS behind one IP address using different DynDNS host names?
I have my second HFS on a second PC with a different port selected.
I have both machines set up with a different static IP address.
In my router I have each PC's HFS port forwarded to that PC's static IP address.
I have a second host name set up with DynDNS.
I have the apropriate host name selected in the DynDNS Updater configuration on each PC.
An HFS self test on the second PC shows successful.
Connecting to it from an outside source using the numerical IP address in the HFS address bar also works fine.
But when the second host name set up at DynDNS is used from an outside source, it takes you to the first HFS in the first PC, not the second.
I scoured the DynDNS site knowledge base and finally found the answer.
I will put it here for others who have the same problem.
After you have set your static ports in your PCs,
and forwarded them in your router,
and set the new port in HFS,
and configured your DynDNS Updater,
Login at DynDNS.
Select the Hostname you want changed.
Change your Service Type to WebHop Redirect.
Copy and past the URL of the second HFS, which includes the alternate port, into the next box down.
And Save Changes.
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