<Example of manual transition>

1. Original state: RAID1

Create spare drives of revertible type. (See "3.15 Creating or Deleting Spare Drives" for details.)

Revertible

2. Occurrence of a fault in PD2

A fault occurs in a physical drive among those configuring a disk array. The disk array is entered into the degraded state (logical drives are entered into the critical state).

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