Creating a DNS Server Configuration
Updated: March 28, 2003
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2
When integrating Active Directory with an existing DNS namespace, it is recommended that you do the following:
Install the DNS Server service on every domain controller in the forest. This provides fault tolerance in the event that one of the DNS servers is unavailable. In this way, domain controllers do not need to rely on other DNS servers for name resolution. This also simplifies the management environment because all domain controllers have a uniform configuration.
Configure the Active Directory forest root domain controller to host the DNS zone for the Active Directory forest.
Configure the domain controllers for each regional domain to host the DNS zones that correspond to their Active Directory domains.
Configure the zone containing the Active Directory forest-wide locator records (_msdcs.forestname zone) to replicate to every DNS server in the forest by using the forest-wide DNS application directory partition.
Active Directory uses forest-wide locator records to enable replication partners find each other and to enable clients to find global catalog servers. Active Directory stores the forest-wide locator records in the _msdcs.forest_name zone. Because the information in the zone must be widely available, this zone is replicated to all DNS servers in the forest by means of the forest-wide DNS application directory partition.
The existing DNS structure remains intact. You do not need to migrate any servers or zones. You simply need to create a delegation to your Active Directory zones from your existing DNS hierarchy.
Configuration When Using Root Hints
Figure 2.32 illustrates the server configuration model for a network that uses root hints. The DNS root zone is hosted on a DNS server at the root of the existing internal DNS infrastructure.
Figure 2.32 Existing DNS Service Configured to Use Root Hints
In this configuration, the DNS servers are configured with root hints that indicate the location of the DNS root servers. When a DNS server needs to resolve a query and cannot resolve it from its cache or zone data, the DNS server queries the DNS servers listed in the root hints.
Configuration When Using Forwarding
Figure 2.33 illustrates the server configuration model for a network that uses forwarding.
Figure 2.33 Existing DNS Service Configured to Use Forwarding
In this configuration, the regional DNS servers that are used to support Active Directory forward queries to the nearest DNS server for the Active Directory forest root, which in turn forwards queries to the standard DNS forwarder that is used by the existing DNS infrastructure.