Promise Technology VTrack M-Class M200i - Manual (Page 267)

Chapter 7: Technology Background
259
Example
Following is an example to explain the Transition function.
In the example above, there is a four-drive RAID 5 disk array and a global spare
drive. Physical drives 1, 2, 3, and 4 belong to the disk array. Physical drive 5
remains unconfigured. Physical drive 6 is a revertible spare drive.
If a physical drive fails in a disk array and there is a spare drive of adequate
capacity available, the controller automatically rebuilds the array using the spare
drive. In this example, physical drive 3 failed and the array is rebuilt using
physical drive 6, the revertible spare drive.
When the rebuild is complete, the spare drive has replaced the failed drive. In this
example, failed drive 3 was replaced by spare drive 6. The disk array now
consists of physical drives 1, 2, 4, and 6.