How to properly configure DNS?

Question

Domain Name System

Good gentlemen and ladies. I inherited a domain of the site.ru type, a domain controller with 3 domains (site.ru, domain, domain.local) (I would have killed the one who did this) in addition to this exch2013 and a bunch of balls tied to the server. There is no possibility to demolish. On the Internet, an external hoster has a website on the site.ru domain, mail and other services on our network. The problem is that not all services that are tied to subdomain.site.ru are available internally from the local network. How can this be corrected?

Answer 1

Split DNS should be done if your exchange is available on private addresses. That is, create a subdomain.site.ru zone on the internal DNS, put all records from the public zone there, but with the addresses that should be accessible from the inside.