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28 Dell PS Series Storage: Choosing a Member RAID Policy | TR1020 | v 4.7
C 16-Disk PS Series array RAID configurations
The following figures shows the response of a 16-disk, PS6000 Series array to failures in the same RAID
set, based on the member RAID policy.
The figures show a logical disk layout. The actual physical layout of disks can change due to administrative
actions. It is not possible to determine which disks are associated with each RAID set.
Note: Adhere to the recommendations in the main section of this document when choosing a member RAID
policy
RAID 10
The following figures shows that using RAID 10 can increase (but cannot guarantee) the chance of an array
surviving multiple disk failures in a 16-disk, PS6000 array. This RAID level is appropriate for mission critical
data with high write intensive random I/O requirements.
In Figure 16, the member RAID policy is RAID 10 with spares. Spares and RAID protect the data.
Surviving disk failures with RAID 10 as the member RAID policy
C.1 RAID 50
The following figures shows that RAID 50 provides more capacity than RAID 10 while continuing to provide
protection from disk failure and good performance and availability for a 16-disk, PS6000 array.
RAID 50 is not recommended for arrays with 1 TB or larger disks. The Dell Group Management GUI will not
allow for any members with 3 TB or higher to be configured with RAID 50 (firmware 7.0.0 and higher)
In Figure 17, the member RAID policy is RAID 50 with spares. Spares and RAID protect the data.