HWN024084W Because the destination storage pools contain one or more copies of the mirrored volumes, the number of volumes that could not be moved from tier source_tier to tier target_tier is number_of_volumes.
Explanation
The primary volume and the secondary volume of a volume in a mirrored volume relationship cannot be placed in the same storage pool.
Action
Ensure that one or more of the destination storage pools that are selected do not contain copies of the mirrored volumes.