To answer your questions, we deploy the unified mangers accross the globe to allign with cdot filers located at these data centers. So yes, a federatated approach would be what we are looking for. Single entry point to find filer capacity and performance statistics unrelated to location of the storage devices.
Currently we try to stay within the max node count per OCUM, so roughly 75. with 140 cDot filers that resulted in 12 installations to date.
As to the archiving, goal is to get all netapp filer capacity and performanced data into our splunk metrics datastore.
Users then can create their own dashboards using netapp metrics but also other metrics already in splunk today,
also, thanks for the link to the oum schemas.