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ONTAP Hardware
Can you upgrade only the controller heads from a FAS2020 to a FAS2040?
Or do you need to purchase a full FAS2040 chassis and move the disks from the FAS2020 to the FAS2040?
Yes. They use the same chassis, so it is a controller swap. Work with your netapp team/var on a quote for new controllers and trade-in on the 2020 controller (if possible to trade-in) then you can have a short outage for the controller swap.