Repadmin helps administrators diagnose Active Directory replication problems between domain controllers running Microsoft Windows operation systems.
You can use Repadmin to view the replication topology, as seen from the perspective of each domain controller.
In addition, you can use Repadmin to manually create the replication topology, to force replication events between domain controllers. You can also use Repadmin to monitor the relative health of an Active Directory Domain Services (AD DS) forest.
- On a domain controller, log in as Domain Administrator.
- Launch “Command Prompt“.
- Enter “repadmin /replsummary“.
The Active Directory replication information was displayed.
By default, the replication model is pull-based in Active Directory, so you should focus on the destination domain controller first.
In the above picture, each dot after the first three represents a domain controller. it isn’t more than 50 dots per line.
Largest delta denotes the longest replication gap amongst all replication links for a particular domain controller.
Total is the replica links for a particular domain controller (one for each naming context on each domain controller). Please note that this is not the connection objects or replication partners per domain controller. I will enter the other command to show it.
Fail is the total number of replica links failing to replicate for one reason or the other. This will never be greater than the Total field.
Percentage is the percentage of failures in relation to the total replica links on the domain controller.
Now, we don’t know the replication information of the current domain controller. I have to enter the following command:
- Enter “repadmin /replsummary %computername%“.
Now, the current domain controller is DC11 and it pulls the replication information from other source DCs.
- I want to get the replication information of DC04, enter “repadmin /replsummary dc04“.
The replication information of dc04 pulls from DC11.
- Enter “repadmin /showrepl dc04” to show the total replication link.
There are 5 replica links for replication. In DC11, there are 45 replica links because it needs to pull all other domain controllers.
To use “repadmin /showrepl“, you can verify the largest delta.
The time replsummary taken was 22:08:33. Now, if you look at the schema naming context replication time, 22:00:44 , the difference is about 7m:, which relates to the largest delta.