You cannot revert ONTAP in a MetroCluster configuration running ONTAP 9.12.1 with IPsec enabled. A check is performed before revert to ensure there are no IPsec configurations within the MetroCluster configuration. You must remove any IPsec configurations present and disable IPsec before continuing with the revert. Reverting ONTAP is blocked if IPsec is enabled, even when you have not configured any user policies.