Enabling and Disabling Replication
You want to enable or disable inbound or outbound replication on a domain controller.
Using a command-line interface
To disable outbound replication on a domain controller, use the following syntax:
> repadmin /options +DISABLE_OUTBOUND_REPL
To re-enable outbound replication, enter the following:
> repamin /options DISABLE_OUTBOUND_REPL
To disable inbound replication, use the following syntax:
> repadmin /options +DISABLE_INBOUND_REPL
To re-enable inbound replication, use the following:
> repadmin /options DISABLE_INBOUND_REPL
When you are making major changes to Active Directory, particularly in cases where you are extending the schema, it is recommended that you disable outbound replication on the DC that you're modifying. This will allow you to test any changes that you've made on a single DC without propagating those changes to the remainder of your directory. If you make a mistake or find that the changes you've made are otherwise unacceptable, you can restore a single DC rather than being faced with the prospect of performing a disaster recovery operation on your entire domain.
It's important to note that disabling outbound replication on a domain controller will not have any effect on inbound replication; the DC in question will still receive updates from its other replication partners unless you disable inbound replication on them as well.
In a worst-case scenario, you can disable replication for an entire forest by issuing the following command:
> repadmin /options * +DISABLE_INBOUND_REPL
MS KB 321153 (How to Disable or Enable Active Directory Replication in Windows 2000)