While double-checking a regular OPC-DA Interface Failover (UniInt Interface-failover) i found the LiveLibrary and the Manuals are incomplete. Both do not indicate the configuration of the Failover settings on the second/backup interface.
See the missing items e.g. here: https://livelibrary.osisoft.com/LiveLibrary/content/en/uni-int-v2/GUID-9ED704DF-0699-408F-91DA-E62AB6A4C949 where the manual stops after the configuration of the first node.
it refers to the UFO point creation on both nodes while these only need to be created on 1 of the failover nodes.
And checking the UnitInt user guide https://customers.osisoft.com/s/productcontent?id=a7R1I000000TTlpUAG , page 36 also does not indicate this should be done on both interfaces.
The YouTube videos are correct though:
OSIsoft: Upgrade to UFO Failover Interfaces Full Walk-through - YouTube (older but better explanation)