You must change the checksum type of an array LUN if you want to add it to an aggregate that has a different checksum type than the checksum type of the LUN.
You should have reviewed the tradeoffs between performance in certain types of workloads and storage capacity utilization of each checksum type. The FlexArray Virtualization Installation Requirements and Reference Guide contains information about checksum use for array LUNs. You can also contact your Sales Engineer for details about using checksums.
You must assign a zoned checksum type to an array LUN that you plan to add to a zoned checksum aggregate or an advanced zoned checksum (AZCS) aggregate. When a zoned checksum array LUN is added to an AZCS aggregate, it becomes an advanced zoned checksum array LUN. Similarly, when a zoned checksum array LUN is added to a zoned aggregate, it is a zoned checksum type.