IBM N Series - Chapter 10. Data Protection with RAID Double Parity

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Chapter 10. Data protection with RAID
Double Parity
This chapter provides an overview of RAID Double Parity (RAID-DP) and describes how it
dramatically increases the data fault tolerance of various disk failure scenarios. Other key
areas that are covered include cost information, special hardware requirements, creating
RAID groups, and converting from RAID 4 to RAID-DP.
This chapter includes a double-disk failure recovery scenario. This scenario shows how
RAID-DP allows the RAID group to continue serving data and re-create the data on the two
failed disks.
This chapter includes the following sections:
򐂰 Background
򐂰 Why use RAID-DP
򐂰 RAID-DP overview
򐂰 RAID-DP and double parity
򐂰 Hot spare disks
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