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Cluster-Mode System Manager Help : Cluster-Mode : Cluster > Storage > Aggregates : Understanding aggregates : Rules for mixing disk types in aggregates

Rules for mixing disk types in aggregates
You can mix disks from different loops or stacks within the same aggregate. Depending on the value of the raid.disktype.enable option, you might be able to mix certain types of disks within the same aggregate.
The following table shows what types of disks can be mixed within an aggregate when the raid.disktype.enable option is set to off:
SAS disks in DS4243 disk shelves
SATA disks in DS4243 disk shelves
FC disks in DS14mk2 FC or DS14mk4 FC disk shelves
ATA disks in DS14mk2 FC or DS14mk4 FC disk shelves
SAS disks in DS4243 disk shelves
SATA disks in DS4243 disk shelves
FC disks in DS14mk2 FC or DS14mk4 FC disk shelves
ATA disks in DS14mk2 FC or DS14mk4 FC disk shelves
*Data ONTAP does not prevent these combinations. However, due to the large difference in performance between the two disk types, you should avoid these combinations.
BSAS disks are considered to be the same as SATA disks in this table.
SAS and SATA disks are not allowed in the same aggregate.
If the raid.disktype.enable option is set to on, all aggregates must contain disks of a single type.
Note: If you set the raid.disktype.enable option to on for a system that already contains aggregates with disks of mixed type, those mixed aggregates continue to function normally and accept both types of disks. However, no other aggregates will accept mixed disk types as long as the raid.disktype.enable option is set to on.
For information about best practices for working with different types of disks, see Technical Report 3437: Storage Best Practices and Resiliency Guide.