Custom ENUM/NAPTR DNS Server

Question

I need to configure custom DNS server to handle ENUM requests for VoIP calls

I have custom built DNS server in Java that handles ENUM requests for my company's VoIP services.

ENUM is used to dynamically route the calls and it uses own routing logic, so that's the reason for custom DNS server rather than standard one like BIND.

When I connect this server directly using dig @my.enum.server.ip everything works OK

The question is how to configure that custom server to be used to handle ENUM requests for my domain, instead of standard DNS server from our hosting provider?

Full query example:

9.8.7.6.5.4.3.2.1.enum.mydomain.com TYPE: NAPTR, class: IN

DNS A record for enum.mydomain.com points to my.enum.server.ip but all DNS queries from the clients are directed to DNS server of our hosting provider, not to my.enum.server.ip causing error response

How to configure enum.mydomain.com itself as responsible for handling that type of queries?

Answer 1

You need to delegate a subdomain (possibly the name(s) of your VOIP servers) to the enum.mydomain.com server. In your parent DNS, assuming voip is the subdomain you want to create, you'd put

 voip IN NS enum.mydomain.com
 enum IN A  A.B.C.D

then on enum put what you need to respond to that (or those) subdomain(s).