What are the correct domain settings @ Go Daddy?

Question

I will set up a Mac Mini Lion Server using server assistant.  I bought a domain name from Go Daddy. What are the correct domain (DNS, host) settings @ Go Daddy - need step by step guide; thanks in advance.

Answer 1

I do not fully understand how the PTR pointer works
PTRs map IP addresses back to hostnames - also known as 'reverse DNS'.
The way it works is that when you (or any client) looks up an IP address they first query the root servers that maintain a map of the main IP address allocations. You then query the server that's authoritative for the IP address in question. That server may respond, or may further delegate responsibility to another server.
As an illustration, imagine a company - MegaISP - who's been allocated a large block of IP addresses - say 1.0.0.0 through 1.255.255.255. As an ISP they provide access service in all 50 states so they may further subdivide their network into chunks and delegate control of each chunk to a different server, e.g. 1.1.0.0 - 1.1.255.255 -> CA, 1.2.0.0 - 1.2.255.255 -> NY, etc.
Now you, as a customer of MegaISP, connect to their server and are allocated a dynamic address from the 1.2.0.0 - 1.2.255.255 subnet - let's say 1.2.3.4
When you perform a reverse lookup on 1.2.3.4 your query first goes to the root servers which say something like 'hey, those IPs are owned by MegaISP's DNS servers, so go ask them'. You then query MegaISP's main servers which then say 'hey, that IP is somewhere in the New York subnet, so go query the New York DNS server. Your query then goes to MegaISP's New York server that replies something like 'host-1-2-3-4.ny.megaisp.net' and that' your reverse lookup.
(of course, this is greatly simplified, and the whole process takes a fraction of a second, but hopefully you get the idea).
The problem you now have is that MegaISP have no idea what services you're running on your connection, so they just return a generic response (e.g. host-1-2-3-4.ny.megaisp.net) and not something that relates to your domain (e.g. www.yourdomain.net). Nobody knows to ask your DNS server what hostname your IP address should map to.
In order for that last step, MegaISP either have to change their DNS servers to map your IP address to your domain name rather than the generic hostname, or they have to further delegate your IP address's lookup to your own server (i.e. add another link in the chain - like 'hey, that IP address is delegated to yourdomain.net, so go ask their server').
Most ISPs are happy to either delegate or have a custom entry for your domain, but not on dynamic or residential-grade connections - it's not worth the time and effort to keep it up to date as your IP address changes, which is why it's typically only something that comes with business-grade services.
and what limitations this will lead to
Any service that relies on valid reverse DNS is doomed to fail. For the most part, http doesn't matter/care, but don't expect to run a mail server or certain other services.