White Papers
Table Of Contents
- 1 Introduction to member RAID policies
- 2 RAID policy availability and performance comparisons
- 3 Setting the member RAID policy
- 4 Displaying the RAID level space distribution
- 5 PS Series array disk layout
- 6 Converting or migrating from a member RAID policy
- 7 Summary
- A 12-Disk PS Series array RAID configurations
- B 14-Disk PS Series array RAID configurations
- C 16-Disk PS Series array RAID configurations
- D 48-Disk PS Series array RAID configurations
- E 42 or 84-disk PS Series RAID configurations
- F Technical support and resources
15 Dell PS Series Storage: Choosing a Member RAID Policy | TR1020 | v 4.7
Surviving disk failures with RAID 10 as the member RAID policy
2.4.3 RAID 50
The following figures show how RAID 50 provides more capacity than RAID 10 while continuing to provide
protection from disk failure and good performance and availability for a 24-disk, PS6210 Series array. RAID
50 has less availability than RAID 10 due to fewer RAID sets that make up the overall RAID 50 policy. RAID
50 can survive only one simultaneous disk failure per RAID 5 set but allows multiple disk failures in a single
array as long as the failed disks fall in different RAID 5 sets.
In the following image, the member RAID policy is RAID 50 with spares. The first image shows no disk
failures. The second image shows two disk failures in different RAID 5 sets, and failures handled in the spare
disks. Spare disks protect the RAID sets up to two disk failures.
Surviving disk failures with RAID 50 as the member RAID policy
Note: RAID 50 is not recommended for HDD larger than 1 TB.