Dell PS Series StorageChoosing a Member RAID Policy Owner's Manual
Summary
This best practices paper provides detailed guidance on choosing RAID policies for Dell PS Series storage arrays. It covers supported RAID levels including RAID 0, 1, 5, 6, and 10, explaining their behavior under normal and failure conditions. The document includes recommendations based on disk sizes, chassis types, and reliability scoring metrics available in SAN HeadQuarters (SANHQ). It addresses large disk considerations and RAID 6 enforcement policies for specific models. Intended for storage administrators and engineers designing or maintaining Dell PS Series SAN environments.
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Dell PS Series Storage: Choosing a Member RAID Policy This paper describes the supported RAID policies for Dell PS Series arrays and provides information on the RAID policies under normal and failure conditions to help administrators choose the appropriate RAID policy. Dell Storage Engineering February 2017
Dell EMC Best Practices
Page Summary Contents For Dell PS Series StorageChoosing a Member RAID Policy Owner's Manual
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Dell PS Series Storage: Choosing a Member RAID Policy This paper describes the supported RAID policies for Dell PS Series arrays and provides information on the RAID policies under normal and failure ...
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Revisions Version Date Description 1.0 2007 Initial Release 4.1 2009 Added RAID 6 4.2 June 2012 Added large disk recommendations and RAID information for 24 disk chassis 4.3 August 2012 Added RAID con...
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Table of Contents 1 Introduction to member RAID policies .......................................................................................................................... 4 1.1 RAID policy de...
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Executive summary One of the most important decisions to make when deploying a new storage solution is which RAID type(s) to use. Each RAID type has its advantages and disadvantages in terms of protec...
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1 Introduction to member RAID policies PS Series arrays include redundant, hot-swappable components- for example physical disks, control modules, fans, and power supplies - for a no-single-point-of-fa...
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1.1 RAID policy descriptions The following RAID policies are available using the PS Series Group Manager GUI or the CLI: RAID 6 – One or more RAID 6 sets, with one or two spare disks. RAID 6 deliver...
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2 RAID policy availability and performance comparisons Although all RAID levels provide good performance and data protection, there are some differences. When choosing a member RAID policy, the perfor...
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0.0 400 GB 800 GB 600 GB 1.2 TB 1 TB 3 TB 4 TB 6 TB SSD SSD 15K 10K 7.2K 7.2K 7.2K 7.2K RAID 6 RAID 10 RAID 50 RAID reliability scores for different PS Series disk types NOTE: The y-axis is the relati...
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Excellent = 1.19 or greater Fair = 0.x to 1.18 Poor = 0 and below SANHQ representation of array reliability SAN Headquarters RAID Policy Reliability Score The RAID policy reliability score in SA...
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2.2 RAID policy impact on performance A PS Series group provides storage to a broad range of environments and delivers good performance for a variety of workloads and applications, regardless of the R...
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Corner testing results Key Observation: As depicted by Figure 3, PS Series had considerable variation in performance amongst the RAID levels for random write I/O, as compared to the other three corner...
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RAID 6 RAID 10 RAID 50 RAID 5 50/50 Random 81% 151% 100% 106% 50/50 Seq 82% 99% 100% 92% Relative performance by RAID policy Key Observation: RAID 10 still offers the best random performance. Another ...
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With RAID 10, data reconstruction involves only two disks (one active and one spare) out of the total number of disks in the array, so the overall performance impact is minimal. With RAID 5 and RA...
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If a set is degraded: Data is reconstructed on the new disk and after reconstruction, performance returns to normal. 2.4 Examples of data protection with different RAID policies The following table an...
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Surviving disk failures with RAID 6 as the member RAID level Example of RAID 6 surviving a double disk failure in each RAID set 2.4.2 RAID 10 The following figures show how using RAID 10 can increase ...
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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...
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2.5 Relative capacity utilization by RAID policy Selection of the RAID policy impacts the capacity utilization of the RAID set in the array. Some RAID levels are more efficient and provide greater usa...
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3 Setting the member RAID policy When a new group is created, or a new member is added to an existing group, the RAID policy must be selected before the space on the member is available. Once the RAID...
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4 Displaying the RAID level space distribution To display the RAID level distribution for PS Series group members, open the Group Manager GUI. In the Group Disk Space panel, select the RAID level spac...
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5 PS Series array disk layout To display the disks in a PS Series array, click: Members > member_name > Disks tab The Member Disks window displays a graphical representation of the disks in an a...
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6 Converting or migrating from a member RAID policy There are different methods available to convert or migrate from one RAID policy to another with PS Series arrays. These options can include: Onli...
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Migration using Group Manager To convert the member RAID policy, open the Group Manager GUI and click: Members > member_name > Modify RAID configuration The Modify RAID Configuration wizard disp...
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Selecting RAID policy 6.3 Array evacuation If the current RAID policy does not support an online conversion and the group has other members with sufficient free space, a member can be converted to any...
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Once those criteria have been met, the volume can be migrated to another storage pool by choosing Move volume option in the Group Manager GUI and selecting the desired storage pool. Move volume window...
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Modify volume settings window 6.4.3 PS Series replication PS Series replication can be used to migrate volume data. Volumes can be migrated using either standard asynchronous replication or in firmwar...
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7 Summary Understanding and using proper RAID levels can be beneficial from a performance perspective and crucial for protection against failures in business critical environments. Dell recommends cho...
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A 12-Disk PS Series array RAID configurations PS4210, PS4100 and PS4110 12-disk RAID Set Relationship RAID Policy Spare Disks RAID Set Relationship Best Practice RAID 6 1 Spare Disk (9+2) Yes RAID 10 ...
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B 14-Disk PS Series array RAID configurations The following table shows the blade version of the PS Series arrays. PS-M4100 and PS-M4110 14-disk RAID Set Relationship RAID Policy Spare Disks RAID Set ...
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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 ...
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Surviving disk failures with RAID 50 as the member RAID policy C.2 RAID 5 Figure 18 shows that RAID 5 provides capacity and protection from disk failure but less availability for a 16- disk, PS6000 ar...
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Surviving disk failures with RAID 6 as the member RAID level 30 Dell PS Series Storage: Choosing a Member RAID Policy | TR1020 | v 4.7
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D 48-Disk PS Series array RAID configurations RAID set relationships for a 48 disk PS Series 65xx array RAID Policy Spare Disks RAID Set Relationship Best Practice RAID 6 1 Spare Disk (12+2) (12+2) (1...
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E 42 or 84-disk PS Series RAID configurations Dell Storage PS6610 arrays are offered in 84 or 42 drive configurations. The hybrid version of the PS6610 is only available in the 84 drive configuration....
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F Technical support and resources Dell.com/support is focused on meeting customer needs with proven services and support. Dell Tech Center is an online technical community where IT professionals have ...
Manual Details
| Brand | Dell |
|---|---|
| Pages | 34 |
| File Size | 1.32 MB |
| Published | June 25, 2026 |
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Frequently Asked Questions
Is RAID 10 recommended for drives larger than 6 TB?
No, RAID 10 is not recommended for HDD or SSD drives greater than 6 TB.
Which RAID policy is available for hybrid arrays?
RAID 6 Accelerated is the only available option for hybrid (mix of HDD and SSD) arrays.
Are RAID 5 and RAID 50 supported on PS6610 arrays?
No, these policies are not available via the Group Manager UI on PS6610 arrays.
What is the recommended RAID policy for a 12-disk PS6610 array?
RAID 6 is recommended, using 2 spare disks in configurations like (12+2).