What are DNS Server Requirements for Exchange Server 2013?

          The Exchange Server must use DNS to locate AD DS and the global catalog servers. As a site-aware application, Exchange Server 2013 prefers to communicate with domain controllers that are located in the same site as the computer that is running Exchange Server.
          Exchange Server services use DNS to locate a valid domain controller or global catalog. By default, each time a domain controller starts the Netlogon service, it updates Domain Name System (DNS) with service (SRV) records that describe the server as a domain controller and global catalog server, if applicable.
          For make sure the domain controller updates DNS records properly, it is essential that all domain controllers we use an internal DNS server that supports dynamic updates. After DNS records are registered, computers that are running Exchange Server can use DNS to find domain controllers and global catalog servers.