Overview#Directory Partition Hierarchy, in Microsoft Active Directory, determines the Hierarchy or the Directory Partition Subtrees
There is an important distinction between the physical storage of a directory partition and its logical position in the directory tree.
Physically, all objects are stored in a single database table, regardless of the directory partition to which they are assigned by virtue of their object names.
Logically, the head of a Domain Directory Partition appears in the naming Hierarchy as the topmost object — that is, the < domain > container, the Configuration container, and the Schema container each has a distinguished name that identifies its position in the hierarchy.
The respective directory partitions contain those objects, which are called "heads"
- the Domain Directory Partition contains an object named dc= domainName
- the Configuration Directory Partition contains an object named cn=configuration,dc=Forest Root Domain
- the Schema Directory Partition contains an object named cn=schema,cn=configuration,dc=Forest Root Domain
- Application Directory Partitions - contain any type of object except for Security Principal Objects.
Figure above shows a conceptual diagram of the directory tree hierarchy, including the directory root (rootDSE) and the default directory partitions below the directory root. In any Active Directory forest, the Configuration Directory Partition and Schema Directory Partition are always in these locations.
Each Domain Controller in the AD Forest holds a master copy (replica) of the Configuration Directory Partition and Schema Directory Partition, which are copied to a Domain Controller during domain controller promotion. All updates to Configuration Directory Partition and Schema Directory Partition are replicated to every Domain Controller in the AD Forest. In this way, site, service, AD DOMAIN, and schema information is kept consistent throughout the AD Forest.
Global Catalog Directory Partition#A Domain Controller that is a Global Catalog server stores one writable Domain Directory Partition and a Partial Attribute Set, read-only replica of every other AD DOMAIN in the AD Forest. Global Catalog ReadOnly replicas contain a Partial Attribute Set of attributes for every object in the AD DOMAIN. It Replicates GC data with all GC’s in the forest. The Global Catalog Partition is created automatically by software on the Domain Controller. This software copies some of the attributes for each object in the Global Catalog Partition. This information is replicated to other Domain Controllers inside and outside the domain. This is how, given enough time, all Global Catalog servers will have a partial replicate of all objects in the domain.
More Information#There might be more information for this subject on one of the following:
- Application Directory Partitions
- Directory Partition Subtrees
- Domain Directory Partition
- Forest Root Domain
- Schema Directory Partition