How to Force Replication Between Domain Controllers

In this article, I’ll show you how to force replication between all domain controllers and specific domain controllers.

You can force replication using the command line or by using Active Directory Sites and Services, I’ll provide examples of using both methods.

Contents

Example 1. Force Domain Controller Replication Across All Sites
Example 2. Push Replication Changes to other Domain Controllers
Example 3. Force Sync a Specific Domain Controller
Example 4. Force Replication using Active Directory Sites and Services

Example 1. Force Domain Controller Replication Across All Sites

In this example, I’ll force replication to all domain controllers across all sites. This will perform a pull replication, meaning it will request changes from other DCs.

Step 1. Log into a domain controller

Step 2. Open the command line as administrator

Step 3. Run the following command

repadmin /syncall /A /e

In the screenshot below, I’m logged into my DC1. When I run the command, it will pull replication from the other DCs.

Step 4. Verify replication

repadmin /showrepl

Flags:

/A – All partitions
/e – Synchronizes domain controllers across all sites in the enterprise. By default, this command does not synchronize domain controllers in other sites.

Example 2. Push Replication Changes to other Domain Controllers

If you want to push change from a source DC to all other domain controllers use this command.

Log into the source DC
Open command prompt as administrator
use the following command.

repadmin /syncall /A /e / P

Flags:

/A – All partitions
/e – Synchronizes domain controllers across all sites in the enterprise. By default, this command does not synchronize domain controllers in other sites.
/P – Pushes changes outward from the specified domain controller.

In this example, I’ll log into DC1, and the replication will be pushed from this DC to my other DCs. I can confirm this by looking at the From and To section of the command output. In the below output the from is my DC1 and the To is my DC2, this confirms it pushing the changes to the other DCs.

Example 3. Force Sync a Specific Domain Controller

To sync a specific domain controller from another DC use this command.

repadmin /syncall DC2 /A

This will pull all changes from the domain controller DC1. For example. I’m logged into DC1 and when I run the command it will pull all changes from DC2 only.

If you want to push all changes from a source DC to a destination DC use the same command just add the /P flag.

repadmin /syncall DC2 /A /P

The above command will push all changes from the DC you are logged into to DC2. This is done by using the /P flag.

Repadmin /syncall Flags

Here is a list of all the flags that can be used with the repadmin /syncall command.

/a – Aborts, if any server is unavailable.
/A – Synchronizes all naming contexts that are held on the home server.
/d – Identifies servers by distinguished name in messages.
/e – Synchronizes domain controllers across all sites in the enterprise. By default, this command does not synchronize domain controllers in other sites.
/h – Displays Help.
/i – Iterates indefinitely.
/I – Runs the repadmin /showrepl command on each server pair in the path instead of synchronizing.
/j – Synchronizes adjacent servers only.
/p – Pauses after every message to allow the user to abort the command.
/P – Pushes changes outward from the specified domain controller.
/q – Runs in quiet mode, which suppresses call back messages.
/Q – Runs in very quiet mode, which reports fatal errors only.
/s – Does not synchronize.
/S – Skips the initial server response check.

Example 4. Force Replication using Active Directory Sites and Services

If you don’t want to use the command line, you can use Active Directory Sites and Services to force replication.

Open Active Directory Sites and Service
Expand Servers
Expand the DC you want to replicate changes to
Click on NTFS Settings
Right click and select “Replicate Now”

This would sync changes to DC1 from DC2. You would need to repeat these steps on the other DCs.

Conclusion

Forcing a DC replication is not something you need to do on a regular basis. If your domain controllers are healthy, they should be replicating every 15 seconds for urgent events and every 3 minutes for non-urgent events. If you are required to frequently force a DC replication then you should troubleshoot the replication issues on your DC. Forcing replication between domain controllers is useful for testing and verification and in situations when a DC might be out of sync.