6.1.2.1 DC Existence
For any DC in the forest, the following objects MUST exist:
nTDSDSA object: See section 6.1.1.
server object: See section 6.1.1.
Domain Controller object (in AD DS, not AD LDS): See section 6.1.1.
For the purposes of this section, an RODC object is a Domain Controller object.
Any one of these objects can be said to "represent" the DC.
Relationships:
The server object is the parent of the nTDSDSA object. On AD DS, the name of the server object is the computer name of the DC; on AD LDS, the name of the server object is the computer name, followed by "$", followed by the instance name of the DC.
On AD DS, the attribute on the server object MUST reference the domain controller object.
On AD DS, the dNSHostName attribute of the domain controller object MUST equal the dNSHostName attribute of the server object.
The dNSHostName attribute of the server object MUST equal the DNS hostname of the computer that is physically the DC.
On AD DS, every value of the servicePrincipalName attribute of the domain controller object, which has a DNS hostname as the instance name (see section 5.1.1.4, "Mutual Authentication", for SPN (2) construction), MUST have an instance name equal to the dNSHostName of the domain controller object.