Please clarify if we would need additional license if tiering from on premise AFF system to Cloud volume Ontap . Kindly see the below note .
A FabricPool license is not required when using StorageGRID as the cloud tier or when using Amazon S3, google Cloud Storage, or Microsoft Azure Blob Storage as the cloud tier for Cloud Volumes for ONTAP.
How will this work , should we use the S3 bucket with Ontap. Is this supported with CVO .
You are correct that you do not need a FabricPool license when tiering from on-prem (AFF/FAS) to StorageGRID or if you tier from CVO to AWS S3, GCP Storage, Azure Blob. Currently you can't tier from on-prem to CVO but you can replicate (snapmirror) from on-prem to CVO then do tiering on the CVO side.
Note: The only time you would need a license is when you are using FabricPool with on-prem to tier directly to a Public Cloud or 3rd party object stores.
CVO has Fabric pool license for free which means every CVO can tier off data to the object storage of that cloud it is running in. While the license is free, the customer will pay the object storage costs.
Cloud Tiering is a totally different solution, also using Fabric pool, in which you tier off data from AFF/FAS to object storage in the cloud.
That one has a license you may need to purchase, though you can do it directly through Cloud Manager as well.
Storage costs are, again, are paid for by the customer.
AFF/FAS DO NOT tier data to CVO.
You can SnapMirror data to CVO who will in turn tier off that data of the secondary copy.
Primary tiering happens to the object storage in the cloud and the storage costs are for the customer.
All of the licenses you may need to buy (FabricPool for Cloud Tiering, and CVO) include support and do not cover the object storage costs.
Cloud Manager is free of license (But need to run 24/7) and includes support as well.