Analysis of information sources in references of the Wikipedia article "Active Directory" in English language version.
examples of how multiple AD objects can be created with the same sAMAccountName
An organizational unit in Active Directory is analogous to a directory in the file system
However, service administrators have abilities that cross domain boundaries. For this reason, the forest is the ultimate security boundary, not the domain.
The Active Directory is made up of one or more naming contexts or partitions.
A site is a set of well-connected subnets.
[...] member servers, [...] belong to a domain but do not contain a copy of the Active Directory data.
[...] a domain controller can locate only the objects in its domain. [...] The global catalog provides the ability to locate objects from any domain [...]
Active Directory uses four distinct directory partition types to store [...] data. Directory partitions contain domain, configuration, schema, and application data.
Domain controllers request (pull) changes rather than send (push) changes that might not be needed.
SMTP can be used to transport nondomain replication [...]
After SQL Server is installed on a computer, you cannot change the computer from a domain controller to a domain member. You must uninstall SQL Server before you change the host computer to a domain member.
Running SQL Server on the same computer as a production Exchange mailbox server is not recommended.
You should attempt to avoid creating potential single points of failure when you plan your virtual domain controller deployment.frank
Trusts enable [...] authentication and [...] sharing resources across domains or forests
Defines several kinds of trusts. (automatic, shortcut, forest, realm, external)
The isMemberOfPartialAttributeSet attribute of an attributeSchema object is set to TRUE if the attribute is replicated to the global catalog. [...] When deciding whether or not to place an attribute in the global catalog remember that you are trading increased replication and increased disk storage on global catalog servers for, potentially, faster query performance.
For security and performance reasons, we recommend that you do not install a standalone SQL Server on a domain controller.
Whenever possible, your domain controllers should run on dedicated servers (physical or virtual).