A. By default, if a client can't find a DC in its local site, then the client will search DNS for any DC that publishes generic service records, and this DC may be located on the other side of the world. Server 2008, Vista, and later clients can take advantage of the Try Next Closest Site feature, which allows the client to use site link information to find a DC in the closest site instead of at random. This feature is disabled by default to maintain default behavior with older clients, but you can enable it using Group Policy:

  1. Open a Group Policy Object (GPO) or create a new one that's linked to a domain, site, or organizational unit with clients you want to use Try Next Closest Site.
  2. Move to Computer Configuration\ Policies\Administrative Templates\System\Netlogon\DC Locator DNS Records.
  3. Double-click Try Next Closest Site in the dialog, shown here, and set it to Enabled. Click OK.

    Click to expand

  4. Close the GPO.

You can also enable Try Next Closest Site manually on specific computers via the registry by setting or creating the DWORD registry value HKLM\System\CurrentControlSet\Services\Netlogon\Parameters\Try Next Closest Site to 1. To disable, set the value to 0.

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