Replication and Sites

Active Directory Replication

Replication ensures all domain controllers maintain synchronized copies of the Active Directory database.

Replication Types:

Intra-Site Replication:

• Fast, uncompressed replication within a site

• Uses RPC (Remote Procedure Call) over IP

• Occurs automatically every 15 seconds for urgent changes

• Change notification triggers immediate replication

Inter-Site Replication:

• Slower, compressed replication between sites

• Uses configurable schedules and intervals

• Can use IP or SMTP transport protocols

• Optimized for WAN connections

Global Catalog Replication:

• Replicates partial attribute set from all domains

• Enables forest-wide searches

• Critical for user logon in multi-domain environments

Replication Topology

Connection Objects:

• Define replication paths between domain controllers

• Created automatically by Knowledge Consistency Checker (KCC)

• Can be manually created for specific requirements

Bridgehead Servers:

• Domain controllers responsible for inter-site replication

• Automatically selected by KCC

• Can be manually designated for specific sites

Replication Partners:

• Domain controllers that replicate directly with each other

• Form replication topology within and between sites

• Maintain up-to-date vectors to track replication state

Site Management

Sites and Subnets:

• Sites represent locations with fast, reliable connections

• Subnets define IP address ranges associated with sites

• Clients automatically discover their site based on IP address

Site Links:

• Define connections between sites for replication

• Include cost values to influence replication paths

• Specify replication schedules and intervals

Site Link Bridges:

• Enable transitive replication between sites

• All site links are bridged by default

• Can be disabled for manual replication control