Setting Forward Lookup Zones in DNS based on the port queried

Question

I have the following problem.
We are using Dynamic DNS to access our site and the modem/router differentiates via port forwarding what server the query goes to based on the port number ie all request go to abc.dyndns.org:port number.
Based on the port eg. port 3389 goes to server1 (192.168.0.1), port 8080 goes to server 2(192.168.0.2), port 80 goes to server 3 (192.168.0.3). This all works well if you are entering from OUTSIDE the local network.
INSIDE the local network, I have setup a Forward Lookup Zone on a Domain server using DNS where the Host A resolves abc.dyndns.org to the local IP address of server 1 (192.168.0.1). This works fine.
How do I get the abc.dyndns.org:other ports to go to the other servers IP addresses as you can only setup one Host A record of  abc.dyndns.org to one address 192.168.0.1, if someone queries from INSIDE the local network as the modem/router does not
come into play?

Answer 1

As I said before, DNS doesn't do this. DNS has nothing to do with ports resolution. It's purely a name to IP or IP to name resolution. THAT'S IT!
But you can port translate each individual port from the WAN IP to different IPs  internally. I thought I said that earlier? Maybe I wasn't clear. I apologize for not fully explaining it, for I thought you understood that part.
Revisiting the bottom of your original post:
INSIDE the local network, I have setup a Forward Lookup Zone on a Domain server using DNS where the Host A resolves abc.dyndns.org to the local IP address of server 1 (192.168.0.1). This works fine.
How do I get the abc.dyndns.org:other ports to go to the other servers IP addresses as you can only setup one Host A record of  abc.dyndns.org to one address 192.168.0.1, if someone queries from INSIDE the local network as the modem/router does not
come into play?
You still have to specify the port internally. Assuming mail.domain.com is server4 (since you didn't specify that port in your original post), you simply create a mail.domain.com zone and give it a blank IP for (making this up) 192.168.0.3, then type in
the same exact thing you would do from the outside:
http://mail.domain.com:8083/folder  
Like I said, it's in the application. DNS just resolve to an IP. There are 65,536 port numbers, and DNS does not deal with resolving any of them. That's the responsibility of the application or service and the client (such as a browser) connecting to
it.
Ace Fekay
MVP, MCT, MCITP/EA, MCTS Windows 2008/R2 & Exchange 2007, Exchange 2010 EA, MCSE & MCSA 2003/2000, MCSA Messaging 2003
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