I am currently running an authorative Bind9 DNS server for a bunch of domains. This authorative server currently replicates to a couple of slaves which are then used to meet the subnet requirement for DNS. The server is currently installed on a bare metal machine with a static WAN IP for itself.
I'd like to move this this server behind a NAT into a virtual machine. Since I don't know all that much about DNS I was wandering: are there any special constraints I need to be aware of when running an authorative DNS behind a NAT? Can I share an IP and route just bind specific ports or do I need to reserve and route a full IP for the DNS services?