HTTPS, DNS and dynamically updating DNS records

Question

Hello to you all, if you are able to help with a DNS problem that I'm having then please accept my thanks and appreciation in advance.
First some background information, I recently  moved my server from my studio to my house where a new purpose built studio will soon be erected. At my old studio any requests for myurl.com came in via the IP (whether that be http, https, ftp etc) from the domain registrar and the router would send the request to the relevant port number whether that be 80 for http or 443 for https etc and all was well as this location had a fixed IP address. Unfortunately at my new location whilst I have a much faster connection I do not have a fixed IP. To get around this I have the following set up (not ideal for a business I know but perfectly OK for home hosting); I set up two psuedo nameservers at no-ip.com (ns1myurl.com and ns2myurl.com) which tracks the changes in my IP address and updates its records accordingly, my registrar then sends any requests to these 'nameservers' and no-ip then forwards it on to my server. So far so good.
The problem arises once the requests get to my server, whilst I have DNS set up, I can only recieve requests from a straight request to the server ie myurl.com will display the site without any problem, but if I then put a www in front of that or try to access the https part of my site (which is set up as a seperate site on the same server) then the server throws an error. I have tried to put an alias (CNAME) into the zone but it does not want to resolve the request. I have searched around but to no avail, I am totally new to DNS so am currently on a steep learning curve and fumbling around in the dark.
The first thing that I need to get working is the request to be resolved correctly and then (and this is where the real fun starts!) is to dynamically update the IP in the DNS records as the IP changes. I will probably have to get help in on this as I understand that this requires BIND of which I know nothing about, first though I'd like to get the pages to be served up correctly. Advice, hints, tips or links to tutorials all greatly appreciated. Full set up listed below.
Many thanks, David.
Xserve PPC G5 running 10.5.8 unlimited set up as standalone OD master
Xraid
APC UPS
CradlePoint MBR1200 Gateway router which acts as the DHCP
http://myurl.com and https://myurl.com set up as 2 seperate sites and located on the Xraid
Current DNS setup:
Primary Zone name: myurl.com with nameservers ns1myurl.no-ip.info and ns2myurl.no-ip.info and allow zone transfers in checked
Then
Name
Type
Value
myurl.com
Primary Zone
        ns1myurl.no-ip.info
        Machine
12.34.56.78 (external IP)
        ns2myurl.no-ip.info
        Machine
12.34.56.78 (external IP)
        myurl.com.
        Machine
12.34.56.78 (external IP)
        www.myurl.com.
        Alias
myurl.com.
With the reverse zone looking thus with allow zone transfers being checked
Name
Type
Value
56.34.12.in-addr.arpa.
Reverse Zone
        12.34.56.78
        Reverse mapping
        myurl.com.

Answer 1

Thanks for the reply Camelot, that part though I had already figured out. I now have this working, all I did was change the external IP to the internal one of the server with resolves with the .local machine name and all is working just fine (for now!). As long as I have primary zones set for each site and any alias or services set up on them then everything works well.. The real test will be when my ISP changes the IP, whilst my tests have proved successful the proof will be when they update the address.
Thanks anyway. David.