Active Directory Cookbook, 3rd Edition

Chapter 12. Replication

12.0. Introduction

Replication is one of the most important and perhaps complex components of Active Directory. The infrastructure behind Active Directory replication, including the site topology, connection objects, and the KCC, was covered in Chapter 11. This chapter focuses strictly on some of the tasks and processes associated with replicating data and checking replication health. For an in-depth overview of how replication works in Active Directory, we suggest reading Active Directory, Fourth Edition, Brian Desmond et al. (O’Reilly).

12.1. Determining Whether Two Domain Controllers Are in Sync

Problem

You want to determine whether two domain controllers are in sync and have no objects to replicate to each other.

Solution

Using a command-line interface

By running the following command you can compare the up-to-dateness vector on the two DCs:

> repadmin /showchanges <DestinationDC's FQDN> <SourceDCGUID> <NamingContext>

For example, the following illustrates the syntax needed to compare the up-to-dateness vectors using dc2.adatumadatum.com as the destination DC and the GUID of dc1.adatum.com as the source, checking replication on the Domain NC:

> repadmin /showchanges dc1.adatum.com 5f09d979-1795-4ca1-9fc3-04efd 2bb721 dc=adatum,dc=com Building starting position from destination server dc1.adatum.com Source Neighbor: dc=adatum,dc=com ==== INBOUND NEIGHBORS ====================================== dc=adatum,dc=com Default-First-Site-Name\DC2 via RPC DC object GUID: ...