In a storage area network having a host device and a consolidated storage array
(CSA), one of the storage arrays of the CSA acts as a primary device of the CSA
to form logical data volumes across one or more of the total storage arrays of
the CSA. The logical data volumes typically have performance requirements that
cannot be met by a single storage array. Upon receipt of a command from the host
device to create one of the logical data volumes, the CSA primary device analyzes
the storage arrays to determine a combination thereof, across which the logical
data volume will be striped, that best satisfies the performance requirements.
The CSA primary device configures these storage arrays to form the logical data
volume and sends striping information, which defines the logical data volume, to
the host device. Striping software based on the host device responds to the striping
information to access the logical data volume. The CSA primary device also manages
the storage arrays and the logical data volume by monitoring the storage arrays
to determine whether any of the storage arrays is about to reach its saturation
point, typically due to changing performance requirements of all of the logical
data volumes on the storage arrays. The CSA primary device then migrates a portion
of one of the logical data volumes from one storage array to another to balance
the data transfer loads on the storage arrays.
