Dell 6 series User manual

www.dell.com | support.dell.com
Dell™ PowerEdge™ Expandable
RAID Controller (PERC) 6/i,
PERC 6/E and CERC 6/i
User’s Guide
Dell_PERC6.2_UG.book Page 1 Wednesday, June 24, 2009 6:08 PM

Notes, Cautions, and Warnings
NOTE: A NOTE indicates important information that helps you make better use of
your system.
CAUTION: A CAUTION indicates potential damage to hardware or loss of data if
instructions are not followed.
WARNING: A WARNING indicates a potential for property damage,
personal injury, or death.
____________________
Information in this document is subject to change without notice.
© 2007–2009 Dell Inc. All rights reserved.
Reproduction of these materials in any manner whatsoever without the written permission of Dell Inc.
is strictly forbidden.
Trademarks used in this text: Dell, the DELL logo, PowerEdge, PowerVault, Dell Precision, and
OpenManage are trademarks of Dell Inc.; MegaRAID is a registered trademark of LSI Corporation;
Microsoft,MS-DOS,WindowsServer,Windows,andWindowsVista areeithertrademarksorregistered
trademarks of Microsoft Corporation in the United States and/or other countries; Citrix XenServer is
a trademark of Citrix Systems Inc. and/or one or more of its subsidiaries, and may be registered in the
U.S.PatentandTrademarkOfficeandinothercountries;VMwareisaregisteredtrademarkofVMware,
Inc. in the United States and/or other jurisdictions; Solaris is a trademark of Sun Microsystems, Inc.;
Intel is a registered trademark of Intel Corporation or its subsidiaries in the United States or other
countries;NovellandNetWareareregisteredtrademarks,andSUSEisa registeredtrademarkofNovell,
Inc. in the United States and other countries; Red Hat and Red Hat Enterprise Linux are registered
trademarks of Red Hat, Inc.
Other trademarks and trade names may be used in this document to refer to either the entities claiming
the marks and names or their products. Dell Inc. disclaims any proprietary interest in trademarks and
trade names other than its own.
Models UCC-60, UCP-60, UCPM-60, and UCP-61
June 2009 Rev. A01
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Contents 3
Contents
1 WARNING: Safety Instructions . . . . . . . . 11
SAFETY: General . . . . . . . . . . . . . . . . . . 11
SAFETY: When Working Inside Your System . . . . . . 12
Protecting Against Electrostatic Discharge . . . . . . 13
SAFETY: Battery Disposal . . . . . . . . . . . . . . . . 14
2Overview. . . . . . . . . . . . . . . . . . . . . . . . . 15
PERC 6 and CERC 6/i Controller Descriptions . . . . . . 15
PCI Architecture . . . . . . . . . . . . . . . . . . 15
Operating System Support . . . . . . . . . . . . . . . . 16
RAID Description . . . . . . . . . . . . . . . . . . . . 16
Summary of RAID Levels . . . . . . . . . . . . . . 17
RAID Terminology. . . . . . . . . . . . . . . . . . 17
3 About PERC 6 and CERC
6/i Controllers . . . . . . . . . . . . . . . . . . . . . 21
PERC 6 and CERC 6 Controller Features . . . . . . . . . 21
Using the SMART Feature . . . . . . . . . . . . . . . . 24
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4Contents
Initializing Virtual Disks . . . . . . . . . . . . . . . . . 25
Background Initialization . . . . . . . . . . . . . . 25
Full Initialization of Virtual Disks . . . . . . . . . . 26
Fast Initialization of Virtual Disks . . . . . . . . . . 26
Consistency Checks . . . . . . . . . . . . . . . . . . . 26
Disk Roaming. . . . . . . . . . . . . . . . . . . . . . . 27
Disk Migration . . . . . . . . . . . . . . . . . . . . . . 27
Compatibility With Virtual Disks Created
on PERC 5 Controllers. . . . . . . . . . . . . . . . 28
Compatibility With Virtual Disks Created
on SAS 6/iR Controllers . . . . . . . . . . . . . . . 28
Migrating Virtual Disks from SAS 6/iR
to PERC 6 and CERC 6/i . . . . . . . . . . . . . . . 29
Battery Management. . . . . . . . . . . . . . . . . . . 30
Battery Warranty Information . . . . . . . . . . . 30
Battery Learn Cycle . . . . . . . . . . . . . . . . . 31
Virtual Disk Write Cache Policies . . . . . . . . . . . . 32
Write-Back and Write-Through. . . . . . . . . . . 32
Conditions Under Which Write-Back
is Employed . . . . . . . . . . . . . . . . . . . . . 32
Conditions Under Which Write-Through
is Employed . . . . . . . . . . . . . . . . . . . . . 33
Conditions Under Which Forced Write-Back
With No Battery is Employed . . . . . . . . . . . . 33
Virtual Disk Read Policies . . . . . . . . . . . . . . . . 33
Reconfiguring Virtual Disks . . . . . . . . . . . . . . . 33
Fault Tolerance Features. . . . . . . . . . . . . . . . . 36
Physical Disk Hot Swapping . . . . . . . . . . . . 36
Failed Physical Disk Detection . . . . . . . . . . . 37
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Contents 5
Redundant Path With Static Load
Balancing Support . . . . . . . . . . . . . . . . . 37
Using Replace Member and Revertible
Hot Spares . . . . . . . . . . . . . . . . . . . . . 37
Patrol Read. . . . . . . . . . . . . . . . . . . . . . . . 38
Patrol Read Feature . . . . . . . . . . . . . . . . 38
Patrol Read Modes . . . . . . . . . . . . . . . . . 39
4 Installing and Configuring Hardware . . . 41
Installing the PERC 6/E and PERC 6/i Adapters . . . . . 41
Installing the Transportable Battery Backup
Unit (TBBU) on PERC 6/E. . . . . . . . . . . . . . . . . 46
Installing the DIMM on a PERC 6/E Adapter . . . . . . 47
Transferring a TBBU Between Controllers . . . . . . . 48
Removing the PERC 6/E and PERC 6/i Adapters . . . . . 49
Removing the DIMM and Battery from a
PERC 6/E Adapter . . . . . . . . . . . . . . . . . . . . 52
Disconnecting the BBU from a PERC 6/i Adapter
or a PERC 6/i Integrated Controller . . . . . . . . . . . 54
Setting up Redundant Path Support on the
PERC 6/E Adapter . . . . . . . . . . . . . . . . . . . . 55
Reverting From Redundant Path Support to Single
Path Support on the PERC 6/E Adapter . . . . . . . . . 58
Removing and Installing the PERC 6/i and CERC 6/i
Integrated Storage Controller Cards in Dell
Modular Blade Systems (Service-Only Procedure) . . . 59
Installing the Storage Controller Card . . . . . . . 60
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6Contents
5 Driver Installation . . . . . . . . . . . . . . . . . 63
Installing Windows Drivers . . . . . . . . . . . . . . . 64
Creating the Driver Media . . . . . . . . . . . . . 64
Pre-Installation Requirements . . . . . . . . . . . 64
Installing the Driver During a Windows
Server 2003 or Windows XP
Operating System Installation. . . . . . . . . . . . 65
Installing the Driver During a Windows Server
2008 or Windows Vista Installation . . . . . . . . . 66
Installing a Windows Server 2003, Windows
Server 2008, Windows Vista, or Windows XP
Driver for a New RAID Controller. . . . . . . . . . 67
Updating an Existing Windows Server 2003,
Windows Server 2008, Windows XP,
or Windows Vista Driver . . . . . . . . . . . . . . 68
Installing Linux Driver . . . . . . . . . . . . . . . . . . 69
Installing Red Hat Enterprise Linux Operating
System Using the Driver Update Diskette . . . . . 71
Installing SUSE Linux Enterprise Server
Using the Driver Update Diskette . . . . . . . . . . 71
Installing the RPM Package With
DKMS Support . . . . . . . . . . . . . . . . . . . 72
Installing Solaris Driver . . . . . . . . . . . . . . . . . 74
Installing Solaris 10 on a PowerEdge System
Booting From a PERC 6 or CERC 6/i Controller . . . 74
Adding/Updating the Driver to an
Existing System . . . . . . . . . . . . . . . . . . . 75
Installing NetWare Drivers . . . . . . . . . . . . . . . 75
Installing the NetWare Driver in a New
NetWare System . . . . . . . . . . . . . . . . . . 75
Installing or Updating the NetWare Driver in
an Existing NetWare System . . . . . . . . . . . . 76
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Contents 7
6 Configuring and Managing RAID. . . . . . . 77
Dell OpenManage Storage Management . . . . . . . . 77
Dell SAS RAID Storage Manager . . . . . . . . . . . . 77
RAID Configuration Functions . . . . . . . . . . . . . . 78
BIOS Configuration Utility . . . . . . . . . . . . . . . . 79
Entering the BIOS Configuration Utility. . . . . . . 79
Exiting the Configuration Utility. . . . . . . . . . . 80
Menu Navigation Controls . . . . . . . . . . . . . 80
Setting Up Virtual Disks. . . . . . . . . . . . . . . 83
Virtual Disk Management . . . . . . . . . . . . . . . . 85
Creating Virtual Disks. . . . . . . . . . . . . . . . 85
Initializing Virtual Disks. . . . . . . . . . . . . . . 88
Checking Data Consistency . . . . . . . . . . . . 88
Importing or Clearing Foreign Configurations
Using the VD Mgmt Menu . . . . . . . . . . . . . 89
Importing or Clearing Foreign
Configurations Using the Foreign
Configuration View Screen . . . . . . . . . . . . . 90
Managing Preserved Cache . . . . . . . . . . . . 93
Managing Dedicated Hot Spares. . . . . . . . . . 94
Deleting Virtual Disks. . . . . . . . . . . . . . . . 95
Deleting Disk Groups . . . . . . . . . . . . . . . . 95
Resetting the Configuration . . . . . . . . . . . . 96
BIOS Configuration Utility Menu Options. . . . . . 96
Physical Disk Management . . . . . . . . . . . . . . . 105
Setting LED Blinking . . . . . . . . . . . . . . . . 105
Creating Global Hot Spares. . . . . . . . . . . . . 105
Removing Global or Dedicated Hot Spares . . . . 106
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8Contents
Replacing an Online Physical Disk . . . . . . . . 107
Stopping Background Initialization . . . . . . . . 108
Performing a Manual Rebuild of an
Individual Physical Disk . . . . . . . . . . . . . . 108
Controller Management . . . . . . . . . . . . . . . . 109
Enabling Boot Support . . . . . . . . . . . . . . 109
Enabling BIOS Stop on Error . . . . . . . . . . . 110
Restoring Factory Default Settings . . . . . . . . 111
7 Troubleshooting . . . . . . . . . . . . . . . . . . . 113
Post Error Messages . . . . . . . . . . . . . . . . . . 113
Virtual Disks Degraded . . . . . . . . . . . . . . . . 119
Memory Errors . . . . . . . . . . . . . . . . . . . . . 120
Pinned Cache State . . . . . . . . . . . . . . . . . . 120
General Problems . . . . . . . . . . . . . . . . . . . 121
Physical Disk Related Issues . . . . . . . . . . . . . 122
Physical Disk Failures and Rebuilds . . . . . . . . . 123
SMART Errors . . . . . . . . . . . . . . . . . . . . . 125
Replace Member Errors . . . . . . . . . . . . . . . . 126
Linux Operating System Errors. . . . . . . . . . . . . 127
Controller LED Indicators . . . . . . . . . . . . . . . 129
Drive Carrier LED Indicators . . . . . . . . . . . . . . 130
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Contents 9
A Regulatory Notices . . . . . . . . . . . . . . . . 133
B Corporate Contact Details (Taiwan Only) 135
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
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10 Contents
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WARNING: Safety Instructions 11
WARNING: Safety Instructions
Use the following safety guidelines to help ensure your own personal safety
and to help protect your system and working environment from potential
damage.
WARNING: There is a danger of a new battery exploding if it is incorrectly
installed. Replace the battery only with the same or equivalent type recommended
by the manufacturer. See "SAFETY: Battery Disposal" on page 14.
NOTE: For complete information about U.S. Terms and Conditions of Sale, Limited
Warranties, and Returns, Export Regulations, Software License Agreement, Safety,
Environmental and Ergonomic Instructions, Regulatory Notices, and Recycling
Information, see the documentation that was shipped with your system.
SAFETY: General
• Observe and follow service markings. Do not service any product except as
explained in your user documentation. Opening or removing covers that
are marked with the triangular symbol with a lightning bolt may expose
you to electrical shock. Components inside these compartments must be
serviced only by a trained service technician.
• If any of the following conditions occur, unplug the product from the
electrical outlet, and replace the part or contact your trained service
provider:
– The power cable, extension cable, or plug is damaged.
– An object has fallen in the product.
– The product has been exposed to water.
– The product has been dropped or damaged.
– The product does not operate correctly when you follow the operating
instructions.
• Use the product only with approved equipment.
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12 WARNING: Safety Instructions
• Operate the product only from the type of external power source indicated
on the electrical ratings label. If you are not sure of the type of power
source required, consult your service provider or local power company.
• Handle batteries carefully. Do not disassemble, crush, puncture, short
external contacts, dispose of in fire or water, or expose batteries to
temperatures higher than 60° Celsius (140° Fahrenheit). Do not attempt
to open or service batteries; replace batteries only with batteries designated
for the product.
SAFETY: When Working Inside Your System
Before you remove the system covers, perform the following steps in the
sequence indicated.
WARNING: Except as expressly otherwise instructed in Dell documentation, only
trained service technicians are authorized to remove the system cover and access
any of the components inside the system.
WARNING: To help avoid possible damage to the system board, wait 5 seconds
after turning off the system before removing a component from the system board or
disconnecting a peripheral device.
1 Turn off the system and any connected devices.
2 Disconnect your system and devices from their power sources. To reduce
the potential of personal injury or shock, disconnect any
telecommunication lines from the system.
3 Ground yourself by touching an unpainted metal surface on the chassis
before touching anything inside the system.
4 While you work, periodically touch an unpainted metal surface on the
chassis to dissipate any static electricity that might harm internal
components.
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WARNING: Safety Instructions 13
In addition, note these safety guidelines when appropriate:
• When you disconnect a cable, pull on its connector or on its strain-relief
loop, not on the cable itself. Some cables have a connector with locking
tabs. If you are disconnecting this type of cable, press in on the locking
tabs before disconnecting the cable. As you pull connectors apart, keep
them evenly aligned to avoid bending any connector pins. Also, when you
connect a cable, make sure both connectors are correctly oriented and
aligned.
• Handle components and cards with care. Do not touch the components or
contacts on a card. Hold a card by its edges or by its metal mounting
bracket. Hold a component such as a microprocessor chip by its edges, not
by its pins.
Protecting Against Electrostatic Discharge
Electrostatic discharge (ESD) events can harm electronic components inside
your system. Under certain conditions, ESD may build up on your body or an
object, such as a peripheral, and then discharge insto another object, such as
your system. To prevent ESD damage, you must discharge static electricity from
your body before you interact with any of your system’s internal electronic
components, such as a memory module. You can protect against ESD by
touching a metal grounded object (such as an unpainted metal surface on
your system’s I/O panel) before you interact with anything electronic. When
connecting a peripheral (including handheld digital assistants) to your system,
you should always ground both yourself and the peripheral before connecting
it to the system. Additionally, as you work inside the system, periodically
touch an I/O connector to remove any static charge your body may have
accumulated.
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14 WARNING: Safety Instructions
You can also take the following steps to prevent damage from electrostatic
discharge:
• When unpacking a static-sensitive component from its shipping carton, do
not remove the component from the antistatic packing material until you
are ready to install the component. Just before unwrapping the antistatic
package, be sure to discharge static electricity from your body.
• When transporting a sensitive component, first place it in an antistatic
container or packaging.
• Handle all electrostatic sensitive components in a static-safe area. If
possible, use antistatic floor pads and work bench pads.
SAFETY: Battery Disposal
Your system may use a nickel-metal hydride (NiMH), lithium
coin-cell, and/or a lithium-ion battery. The NiMH, lithium coin-
cell, and lithium-ion batteries are long-life batteries, and it is
possible that you will never need to replace them. However, should
you need to replace them, see the instructions included in the
section "Configuring and Managing RAID" on page 77.
NOTE: Do not dispose of the battery along with household waste. Contact your
local waste disposal agency for the address of the nearest battery deposit site.
NOTE: Your system may also include circuit cards or other components that
contain batteries. These batteries too must be disposed of in a battery deposit site.
For information about such batteries, see the documentation for the specific card or
component.
Taiwan Battery Recycling Mark
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Overview 15
Overview
The Dell™ PowerEdge™ Expandable RAID Controller (PERC) 6 family of
controllers and the Dell Cost-Effective RAID Controller (CERC) 6/i offer
redundant array of independent disks (RAID) control capabilities. The PERC 6
and CERC 6/i Serial Attached SCSI (SAS) RAID controllers only support
Dell-qualified SAS and SATA hard disk drives (HDD) and solid-state
drives (SSD). The controllers are designed to provide reliability, high
performance, and fault-tolerant disk subsystem management.
PERC 6 and CERC 6/i Controller Descriptions
The following list describes each type of controller:
• The PERC 6/E Adapter with two external x4 SAS ports and a transportable
battery backup unit (TBBU)
• The PERC 6/i Adapter with two internal x4 SAS ports, with or without a
battery backup unit, depending on the system
• The PERC 6/i Integrated controller with two internal x4 SAS ports and a
battery backup unit
• The CERC 6/i Integrated controller with one internal x4 SAS port and no
battery backup unit
Each controller supports up to 64 virtual disks.
NOTE: The number of virtual disks supported by the PERC 6/i and the CERC 6/i
cards is limited by the configuration supported by the system.
PCI Architecture
• PERC 6 controllers support a Peripheral Component Interconnect
Express (PCI-E) x8 host interface.
• CERC 6/i Modular controllers support a PCI-E x4 host interface.
NOTE: PCI-E is a high-performance input/output (I/O) bus architecture designed to
increase data transfers without slowing down the Central Processing Unit (CPU).
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16 Overview
Operating System Support
The PERC 6 and CERC 6/i controllers support the following operating systems:
• Citrix
®
XenServer
®
Dell Edition
• Microsoft
®
Windows Server
®
2003
• Microsoft Windows
®
XP
• Microsoft Windows Vista
®
• Microsoft Windows Server 2008 (including Hyper-V™ virtualization)
•Novell
®
NetWare
®
6.5
•RedHat
®
Enterprise Linux
®
Version 4 and Red Hat Enterprise
Linux Version 5
• Solaris™ 10 (64-bit)
•SUSE
®
Linux Enterprise Server Version 9 (64-bit), Version 10 (64-bit),
and Version 11 (64-bit)
•VMware
®
ESX 3.5 and 3.5i
NOTE: Windows XP and Windows Vista operating systems are supported with a
PERC 6 controller only when the controller is installed in a Dell Precision™
workstation.
NOTE: For the latest list of supported operating systems and driver installation
instructions, see the system documentation on the Dell Support website
at support.dell.com. For specific operating system service pack requirements,
see the Drivers and Downloads section on the Dell Support site at support.dell.com.
RAID Description
RAID is a group of independent physical disks that provides high performance by
increasing the number of drives used for saving and accessing data. A RAID disk
subsystem improves I/O performance and data availability. The physical disk
group appears to the host system either as a single storage unit or multiple
logical units. Data throughput improves because several disks are accessed
simultaneously. RAID systems also improve data storage availability and fault
tolerance. Data loss caused by a physical disk failure can be recovered by rebuilding
missing data from the remaining physical disks containing data or parity.
CAUTION: In the event of a physical disk failure, a RAID 0 virtual disk fails,
resulting in data loss.
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Overview 17
Summary of RAID Levels
• RAID 0 uses disk striping to provide high data throughput, especially for
large files in an environment that requires no data redundancy.
• RAID 1 uses disk mirroring so that data written to one physical disk is
simultaneously written to another physical disk. RAID 1 is good for small
databases or other applications that require small capacity, but also require
complete data redundancy.
• RAID 5 uses disk striping and parity data across all physical disks
(distributed parity) to provide high data throughput and data redundancy,
especially for small random access.
• RAID 6 is an extension of RAID 5 and uses an additional parity block.
RAID 6 uses block-level striping with two parity blocks distributed across
all member disks. RAID 6 provides protection against double disk failures,
and failures while a single disk is rebuilding. If you are using only one array,
deploying RAID 6 is more effective than deploying a hot spare disk.
• RAID 10, a combination of RAID 0 and RAID 1, uses disk striping across
mirrored disks. It provides high data throughput and complete data
redundancy. RAID 10 can support up to eight spans, and up to 32 physical
disks per span.
• RAID 50, a combination of RAID 0 and RAID 5, uses distributed data
parity and disk striping and works best with data that requires high system
availability, high request rates, high data transfers, and medium to large
capacity.
• RAID 60 is a combination of RAID 6 and RAID 0, a RAID 0 array is striped
across RAID 6 elements. RAID 60 requires at least 8 disks.
RAID Terminology
Disk Striping
Disk striping allows you to write data across multiple physical disks instead of
just one physical disk. Disk striping involves partitioning each physical disk
storage space in stripes of the following sizes: 8 KB, 16 KB, 32 KB, 64 KB,
128 KB, 256 KB, 512 KB, and 1024 KB. These stripes are interleaved in a
repeated sequential manner. The part of the stripe on a single physical disk is
called a stripe element.
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18 Overview
For example, in a four-disk system using only disk striping (used in RAID 0),
segment 1 is written to disk 1, segment 2 is written to disk 2, and so on. Disk
striping enhances performance because multiple physical disks are accessed
simultaneously, but disk striping does not provide data redundancy.
Figure 2-1 shows an example of disk striping.
Figure 2-1. Example of Disk Striping (RAID 0)
Disk Mirroring
With mirroring (used in RAID 1), data written to one disk is simultaneously
written to another disk. If one disk fails, the contents of the other disk can be
used to run the system and rebuild the failed physical disk. The primary
advantage of disk mirroring is that it provides complete data redundancy.
Because the contents of the disk are completely written to a second disk, it
does not matter if one of the disks fails. Both disks contain the same data at
all times. Either of the physical disks can act as the operational physical disk.
Disk mirroring provides complete redundancy, but is expensive because each
physical disk in the system must be duplicated.
NOTE: Mirrored physical disks improve read performance by read load balance.
Stripe element 1
Stripe element 5
Stripe element 9
Stripe element 2
Stripe element 6
Stripe element 10
Stripe element 3
Stripe element 7
Stripe element 11
Stripe element 4
Stripe element 8
Stripe element 12
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Overview 19
Figure 2-2 shows an example of disk mirroring.
Figure 2-2. Example of Disk Mirroring (RAID 1)
Spanned RAID Levels
Spanning is a term used to describe the way in which RAID levels 10, 50,
and 60 are constructed from multiple sets of basic, or simple RAID levels.
For example, a RAID 10 has multiple sets of RAID 1 arrays where each RAID 1
set is considered a span. Data is then striped (RAID 0) across the RAID 1
spans to create a RAID 10 virtual disk. If you are using RAID 50 or RAID 60,
you can combine multiple sets of RAID 5 and RAID 6 together with striping.
Parity Data
Parity data is redundant data that is generated to provide fault tolerance
within certain RAID levels. In the event of a drive failure the parity data can
be used by the controller to regenerate user data. Parity data is present for
RAID 5, 6, 50, and 60.
The parity data is distributed across all the physical disks in the system. If a
single physical disk fails, it can be rebuilt from the parity and the data on the
remaining physical disks. RAID level 5 combines distributed parity with disk
striping, as shown in Figure 2-3. Parity provides redundancy for one physical
disk failure without duplicating the contents of entire physical disks.
RAID 6 combines dual distributed parity with disk striping. This level of
parity allows for two disk failures without duplicating the contents of entire
physical disks.
Stripe element 1
Stripe element 2
Stripe element 3
Stripe element 1 Duplicated
Stripe element 2 Duplicated
Stripe element 3 Duplicated
Stripe element 4 Stripe element 4 Duplicated
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20 Overview
Figure 2-3. Example of Distributed Parity (RAID 5)
NOTE: Parity is distributed across multiple physical disks in the disk group.
Figure 2-4. Example of Dual Distributed Parity (RAID 6)
NOTE: Parity is distributed across all drives in the array.
Stripe element 1
Stripe element 7 Stripe element 2 Stripe element 8 Stripe element 3 Stripe element 9 Stripe element 4 Stripe element 10 Stripe element 5 Parity (6–10)
Parity (11–15)
Parity (1–5)
Stripe element 6
Stripe element 12
Stripe element 15 Stripe element 11Stripe element 14 Stripe element 13
Stripe element 19
Stripe element 25 Stripe element 20 Stripe element 23 Stripe element 18 Stripe element 21 Stripe element 16 Stripe element 22 Stripe element 17
Parity (21–25)
Parity (26–30)
Parity (16–20) Stripe element 24
Stripe element 30
Stripe element 27 Stripe element 29
Stripe element 26 Stripe element 28
Stripe element 1
Stripe element 5 Stripe element 2 Stripe element 6 Stripe element 3 Parity (5–8) Stripe element 4 Parity (5–8) Parity (1–4)
Stripe element 7
Stripe element 10
Parity (1–4)
Stripe element 8
Stripe element 12
Stripe element 9 Stripe element 11
Parity (9–12)
Parity (9–12)
Stripe element 13 Stripe element 14 Stripe element 16Parity (13–16) Stripe element 15
Parity (13–16)
Dell_PERC6.2_UG.book Page 20 Wednesday, June 24, 2009 6:08 PM