Under Monitored FRS replica sets, choose the replica set
for which you want to change the reference domain controller.
If you have recently made changes to the FRS topology and those
changes don’t appear in this dialog box, click the Sync
Topology button to force a manual poll of Active Directory
information for the selected replica sets
Under Ultrasound Reference Sources, next to Reference
DC, click the Change DC button.
Under Change Ultrasound reference DC to, click the
domain controller to act as the reference domain controller.
Under Apply change to, click one of the following:
Current selected replica set to change the reference
domain controller for only the selected replica set
All replica sets referring to the current DC to select a
new reference domain controller for all replica sets that use the
server shown in Current DC as a reference domain controller.
Choosing this setting is useful if you are decommissioning the
current domain controller and want a number of replica sets to use
another reference domain controller that is common to those replica
sets.
All replica sets in the current domain to use the newly
selected reference domain controller for all replica sets in the
domain.