Configuring Name Resolution for Disjointed Namespaces
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2
If you need to create or merge two DNS namespaces when you deploy Windows Server 2003 DNS, this can result in disjointed namespaces — a DNS infrastructure that includes two or more top-level DNS domain names. To configure internal name resolution for multiple DNS top-level domains, you must do one of the following:
If you have an internal DNS root, add delegations for each top-level DNS zone to the internal DNS root zone.
If you want to reduce cross-domain DNS query traffic, configure the DNS servers that host the DNS zones in the first and second namespaces to host secondary zones for the DNS zones in each other’s namespaces. In this configuration, the DNS servers that host the DNS zones in each namespace are aware of the DNS servers in the other namespace. This solution requires increased storage space for hosting secondary copies of zones in different namespaces, and generates increased zone transfer traffic.
If storage capacity on DNS servers is a consideration, configure the DNS servers that host the DNS zones in one namespace to forward name resolution queries in a second namespace to the DNS servers that are hosting the DNS zones for the second namespace. Then configure the DNS servers that host the DNS zones in the second namespace to forward name resolution queries in the first namespace to the DNS servers that are hosting the DNS zones for the first namespace. You can use Windows Server 2003 DNS conditional forwarders for this configuration.
You can also use Windows Server 2003 DNS stub zones to facilitate DNS data distribution between separate namespaces. For more information about conditional forwarders and stub zones, see Help and Support Center for Windows Server 2003 and the Networking Collection of the Windows Server 2003 Technical Reference (or see the Networking Collection on the Web at https://www.microsoft.com/reskit).