Hi,
The best practice is to align the active directory topology with your network topology. I recommend you to to perform the following actions through the console "sites and services active directory":
- Create a active directory site for each remote site
- Move the closest domain controller on active directory site
- Create a subnet for each remote physical site and assign it to the active directory site where there is the closest domain controller
Once you complete those steps, the client will find the closest domain controller based on active directory topology via dclocator process.
active-directory-replication-concepts
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