Fairly noobish question, kind of ashamed to be asking ;-)
At any rate, I'm using a commercial control panel (similar to Plesk) that I use to manage DNS. I have ns1.example.com setup with the registrar, and a secondary ns with zoneedit -- both point to a public ip in my /27.
The name server lives behind a Cisco ASA; transferred the example.com site to the new server, everything works fine; however, it occurred to me just now: I need to get the colo facility to provide reverse DNS on example.com, and I have the example.com site on a different public ip than ns1.example.com
Have I screwed the pooch or is this in fact the correct approach? i.e. name server listens on its own dedicated ip with just port 53 udp traffic open, and then all domains handled by the name server live on different public ips?
Would appreciate a good word here before I blindly try to fix what may not be broken ;-)
Thanks
Reverse DNS is not required for anything but mail servers, due to spam checking there. However it does help identify what a IP is used for. Name servers and Web servers may live on different IP's. it seems your setup is fine.
Domain can't "live on IP" - domain is a family of hosts, which can live on different and even unrelated IPs.
DNS and reverse-DNS are the areas of unrelated (in common) responsibility:
You must find owner of of ip-block and ask IN PTR records for used by you IPs