3.Hot spare rebuild is done by using PD4 to create a logical drive having PD1, PD3 and PD4 as configured HDDs.

4.Replace the defected physical drive with a new physical drive having a capacity equal to or larger than the capacity of the defected drive.

5.Transition is automatically started to move data from the spare drive to the new physical drive.

6.When the transition is completed, the new physical drive becomes a member of the original logical drive. The spare drive having saved the data temporarily returns to the original spare drive.

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