Broadcom RAIDCore BC4000 Series User manual

BC4000-UM100-R

16215 Alton Parkway • P.O. Box 57013 • Irvine, CA 92619-7013 • Phone: 949-450-8700 • Fax: 949-450-8710 02/13/06

User Manual

BC4000

RAIDCore™ BC4000 Series RAID

Controllers

Broadcom

®

, the pulse logo, Connecting everything

®

, and the Connecting everything logo are among the trademarks of

Broadcom Corporation and/or its affiliates in the United States, certain other countries and/or the EU. Any other

trademarks or trade names mentioned are the property of their respective owners.

This user guide (including, without limitation, the Broadcom component(s) identified herein) is not designed, intended,

or certified for use in any military, nuclear, medical, mass transportation, aviation, navigations, pollution control,

hazardous substances management, or other high risk application. BROADCOM PROVIDES THIS USER GUIDE "AS-

IS", WITHOUT WARRANTY OF ANY KIND. BROADCOM DISCLAIMS ALL WARRANTIES, EXPRESSED AND

IMPLIED, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS

FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT.

Broadcom Corporation

P.O. Box 57013

16215 Alton Parkway

Irvine, CA 92619-7013

Printed in the U.S.A.

REVISION HISTORY

Revision Date Change Description

BC4000-UM100-R 02/13/06 Initial release; describes version 2.1 of XelCore™ software and the

BC4000 Series of hardware controllers (which includes HT-1000

controllers).

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TABLE OF CONTENTS

Section 1: Introduction........................................................................................................1

Audience ....................................................................................................................................................... 1

Obtaining Acrobat ........................................................................................................................................ 1

Contacting Broadcom.................................................................................................................................. 1

Section 2: Overview of RAID Concepts .............................................................................2

Understanding Arrays ................................................................................................................................. 2

Overview of Array Types ............................................................................................................................. 2

Expanding Disk Capacity Online ................................................................................................................ 3

Migrating RAID Levels Online ..................................................................................................................... 3

Performance Considerations ...................................................................................................................... 4

Reliability Considerations ........................................................................................................................... 4

Flexibility and Expansion Considerations................................................................................................. 5

Multiple Types......................................................................................................................................... 5

Future Expansion .................................................................................................................................... 5

Operating System Considerations ............................................................................................................. 5

Section 3: General Product Information............................................................................6

Overview of Features ................................................................................................................................... 6

BC4000 Series Model Numbers .................................................................................................................. 7

BC485x and BC445x Controllers ............................................................................................................ 7

BC4810 and BC4410 Controllers............................................................................................................ 8

HT-1000 Controllers................................................................................................................................ 9

Licensing Level Differences........................................................................................................................ 9

Detailed Feature List.................................................................................................................................. 10

Section 4: Installing BC4000 Series Controllers.............................................................12

Overview of the Installation Process ....................................................................................................... 12

System Requirements........................................................................................................................... 12

BC4000 Series Kit Contents ................................................................................................................. 13

Installation Steps................................................................................................................................... 13

Installing and Cabling BC4000 Hardware ................................................................................................ 15

Installing the BC4000 Controller ........................................................................................................... 15

Installing Hard Disk Drives and Cables (BC4000) ................................................................................ 17

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Preparing Disks and Arrays for New OS Installs.....................................................................................19

Initializing Disks from the BIOS .............................................................................................................19

Creating Arrays from the BIOS..............................................................................................................20

Windows: Installing Drivers and Applications.........................................................................................22

Transferring Drivers to Floppy Disk (Windows) .....................................................................................22

Installing the BC4000 Series Drivers (Windows)...................................................................................22

New Installation of Windows 2000, XP, or 2003 ...........................................................................23

Existing Installation of Windows 2000, XP, or 2003.......................................................................24

Installing the Management Suite ...........................................................................................................27

Linux: Installing Drivers and Applications...............................................................................................28

Transferring Drivers to Floppy Disk (Linux) ...........................................................................................28

Installing the BC4000 Series Drivers (Linux).........................................................................................29

New Install of Red Hat and Fedora Core 1 Linux...........................................................................29

New Install of Fedora Core 2, 3, and 4 Linux .................................................................................30

New Install of SuSE Linux..............................................................................................................30

Existing Install of Red Hat or Fedora Core 1, 2, 3, or 4 Linux........................................................31

Existing Install of SuSE Linux.........................................................................................................32

Installing the bcadm Application............................................................................................................33

Installing the Online Help.......................................................................................................................33

Installing the bc_winraid Application......................................................................................................34

Booting from a Legacy Disk ......................................................................................................................35

Section 5: Updating the Drivers, Firmware, and Applications...................................... 36

Updating Components for the BC4000 Series .........................................................................................36

Updating the BC4000 Series Components for Windows.......................................................................37

Updating the BC4000 Series Driver for Linux........................................................................................39

Updating the BC4000 Series BIOS Image (Linux) ................................................................................40

Updating the BC4000 Driver for a Linux Errata Kernel..........................................................................41

Creating a Bootable Floppy Disk ..............................................................................................................42

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Section 6: General Concepts for Managing Arrays and Disks ......................................43

RAID Minimum Disk Requirements .......................................................................................................... 43

Using Legacy Disks ................................................................................................................................... 43

Understanding Array and Disk States...................................................................................................... 44

Array States .......................................................................................................................................... 44

Disk States............................................................................................................................................ 45

Rescanning for Changes in State ......................................................................................................... 45

Starting and Stopping Tasks .................................................................................................................... 46

Working with Spares.................................................................................................................................. 47

About Sparing Options .......................................................................................................................... 47

Using Distributed Sparing ..................................................................................................................... 47

Using Dedicated Sparing ...................................................................................................................... 49

Using Global Sparing ............................................................................................................................ 49

Section 7: Using the BIOS Configuration Utility.............................................................50

When to Use the BIOS Configuration Utility............................................................................................ 50

Understanding the Color Code in the BIOS............................................................................................. 50

Initializing Disks from the BIOS................................................................................................................ 51

Creating Arrays from the BIOS ................................................................................................................. 52

Deleting Arrays from the BIOS ................................................................................................................. 54

Swapping Arrays from the BIOS............................................................................................................... 55

Hiding or Unhiding Arrays from the BIOS ............................................................................................... 56

Viewing Disk Details from the BIOS ......................................................................................................... 56

Viewing Array Details from the BIOS ....................................................................................................... 57

Rescanning All Channels from the BIOS ................................................................................................. 57

Changing Controller Options From the BIOS.......................................................................................... 58

Continue Booting from the BIOS .............................................................................................................. 59

Section 8: Using RAIDConsole.........................................................................................60

Starting the RAIDConsole Management Application.............................................................................. 60

Using Password Protection ...................................................................................................................... 62

Using the Help Menu.................................................................................................................................. 64

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Reviewing the Interface..............................................................................................................................65

The Array Status Window......................................................................................................................65

Array View Elements .............................................................................................................................66

Disk List Elements .................................................................................................................................67

Array List Elements ...............................................................................................................................67

I/O Status Bar Elements ........................................................................................................................68

Working with Disks.....................................................................................................................................69

Initializing Disks .....................................................................................................................................69

Rescanning Disks..................................................................................................................................69

Changing Cache Settings for Disks.......................................................................................................69

Changing Disk View Settings ................................................................................................................70

Using LEDs to Identify Disks .................................................................................................................72

Working with Arrays...................................................................................................................................72

Creating and Formatting Arrays ............................................................................................................72

Creating Arrays Larger Than 2 TB ........................................................................................................75

Naming Arrays.......................................................................................................................................83

Using LEDs to Identify Arrays................................................................................................................83

Transforming Arrays ..............................................................................................................................84

Copying Arrays......................................................................................................................................85

Using the Un-Link Command .........................................................................................................89

Accessing Additional Space ..................................................................................................................90

Hiding and Unhiding Arrays...................................................................................................................90

Preparing to Physically Remove an Array ............................................................................................. 91

Deleting Arrays......................................................................................................................................91

Recovering Arrays.................................................................................................................................92

Changing Cache Settings for Arrays .....................................................................................................92

Changing the Priority Level of a Task....................................................................................................93

Interrupting or Cancelling a Task...........................................................................................................93

Checking for Consistency......................................................................................................................94

Scheduling a Consistency Check..........................................................................................................95

Scanning an Array in the Background ...................................................................................................95

Splitting Mirrored Arrays........................................................................................................................96

Split a Mirror Using the Default Settings ........................................................................................96

Split a Mirror Using the Advanced Split Option ..............................................................................96

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Adding or Removing Distributed Spares............................................................................................... 97

Adding or Removing Dedicated Spares................................................................................................ 97

Adding or Removing Global Spares...................................................................................................... 98

Removing Spares ................................................................................................................................. 98

Working with Options ................................................................................................................................99

Viewing or Changing the License Level................................................................................................ 99

Changing Your Password Settings ..................................................................................................... 102

Changing the Interface View............................................................................................................... 103

Setting Small Icons ...................................................................................................................... 103

Using Expand On Click................................................................................................................ 103

Editing Text Columns in the Disk List .......................................................................................... 104

Editing the Physical View of the Disks ................................................................................................ 104

Viewing Logs....................................................................................................................................... 105

Setting Event Notifications .................................................................................................................. 106

Setting up Remote Management ........................................................................................................ 108

Adding a Remote System ................................................................................................................... 109

Updating the Controller Firmware ....................................................................................................... 110

Reading SMART Information from Disks ............................................................................................111

Turning on Advanced Options ............................................................................................................ 113

Stopping and Restarting the RAIDCore Service ................................................................................. 113

Section 9: Using bcadm ..................................................................................................114

What is bcadm?........................................................................................................................................ 114

Understanding Query Output.................................................................................................................. 115

bcadm Controller List Elements .......................................................................................................... 115

bcadm Disk List Elements................................................................................................................... 115

bcadm Array List Elements ................................................................................................................. 116

Viewing Help from the Command Line................................................................................................... 117

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Managing Controllers, Arrays, and Disks: bcadm --manage................................................................118

Options ................................................................................................................................................118

--query, -q.....................................................................................................................................118

--query-all, -qa..............................................................................................................................118

--add-spare, -as............................................................................................................................119

--remove-spare, -rs.......................................................................................................................119

--remove-all-spares, -ras..............................................................................................................119

--add-global-spare, -ags...............................................................................................................119

--remove-global-spare, -rgs..........................................................................................................120

--cache-array, -ca .........................................................................................................................120

--cache-disk, -cd...........................................................................................................................121

--check-start, -cs...........................................................................................................................121

--check-end, -ce ...........................................................................................................................122

--check-bitmap-start, -cbs.............................................................................................................122

--check-bitmap-end, -cbe .............................................................................................................122

--scan-array, -sa...........................................................................................................................123

--task, -t ........................................................................................................................................123

--priority, -p...................................................................................................................................124

--initialize disk, -id.........................................................................................................................124

--blink, -b ......................................................................................................................................125

--prepare-to-remove, -ptr..............................................................................................................125

--recover-array, -rcv......................................................................................................................126

--rescan, -rsc ................................................................................................................................126

--hide, -h.......................................................................................................................................126

--unhide, -uh.................................................................................................................................127

--unlink, -ul....................................................................................................................................127

--name, -n.....................................................................................................................................127

--smart-get, -sg.............................................................................................................................128

--flash, -f .......................................................................................................................................128

--array, -a......................................................................................................................................128

--controller, -ct .............................................................................................................................129

--disk, -d .......................................................................................................................................129

--verbose, -v .................................................................................................................................129

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Creating New Arrays: bcadm --create .................................................................................................... 130

Syntax ................................................................................................................................................. 130

Options................................................................................................................................................ 131

--sub-member <num>, -sub <num>............................................................................................. 131

--spare-disk <list>, -sp <list>........................................................................................................ 131

--size <size_mb>, -s <size_mb>..................................................................................................131

--no-sync, -ns............................................................................................................................... 131

--d-spare, -ds ............................................................................................................................... 131

--cache <r, rw, w, nc>, -ca <r, rw, w, nc>..................................................................................... 131

--max-size, -ms ............................................................................................................................ 131

--name "name", -n "name" ........................................................................................................... 131

--priority <1...10>, -p <1...10>...................................................................................................... 132

--preferred-id <64bit_hex>, -pid <64bit_hex> .............................................................................. 132

--scan-array, -sa .......................................................................................................................... 132

--leave-existing-data, -led ............................................................................................................ 132

--disk, -d....................................................................................................................................... 132

Examples ............................................................................................................................................ 132

Deleting Arrays: bcadm --delete ............................................................................................................. 133

Syntax ................................................................................................................................................. 133

Options................................................................................................................................................ 133

Examples ............................................................................................................................................ 133

Transforming Arrays: bcadm --transform.............................................................................................. 134

Syntax ................................................................................................................................................. 134

Options................................................................................................................................................ 135

--sub-member <num>, -sub <num>............................................................................................. 135

--size <size_mb>, -s <size_mb>..................................................................................................135

--same-size, -ss ........................................................................................................................... 135

--d-spare, -ds ............................................................................................................................... 135

--max-size, -ms ............................................................................................................................ 135

--priority <1…10>, -p <1…10>..................................................................................................... 135

--array, -a ..................................................................................................................................... 135

--disk, -d....................................................................................................................................... 135

Examples ............................................................................................................................................ 136

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Copying Arrays: bcadm --create-copy....................................................................................................136

Syntax..................................................................................................................................................136

Options ................................................................................................................................................137

--sub-member, -sub......................................................................................................................137

--spare-disk, -sp ...........................................................................................................................137

--size, -s........................................................................................................................................137

--d-spare, -ds................................................................................................................................137

--unlink, -ul....................................................................................................................................137

--cache, -ca ..................................................................................................................................137

--max-size, -ms.............................................................................................................................138

--name, -n.....................................................................................................................................138

--priority, -p...................................................................................................................................138

--scan-array, -sa...........................................................................................................................138

--array, -a......................................................................................................................................138

--disk, -d .......................................................................................................................................138

Examples.............................................................................................................................................138

Splitting Mirrored Arrays: bcadm --split.................................................................................................139

Syntax..................................................................................................................................................139

Options ................................................................................................................................................139

--no-hide, -nh................................................................................................................................139

--default, -def................................................................................................................................140

--array, -a......................................................................................................................................140

--disk, -d .......................................................................................................................................140

Examples.............................................................................................................................................140

Following or Monitoring Arrays and Disks: bcadm --follow.................................................................141

Linux Syntax and Options....................................................................................................................141

--test-mail, -tm ..............................................................................................................................141

--mail-address <to_email_address>, -ma <to_email_address> ...................................................141

--from_user <from_email_address>, -fu <from_email_address> .................................................142

--program <program>, -p <program> ..........................................................................................142

--delay <seconds>, -d <seconds> ................................................................................................142

--scan, -s ......................................................................................................................................142

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Windows Syntax and Options ............................................................................................................. 142

--test-mail, -tm.............................................................................................................................. 143

--mail-address <to_email_address>, -ma <to_email_address>................................................... 143

--mail-server <email_server>, -ms <email_server> ..................................................................... 143

--from_user <from_email_address>, -fu <from_email_address>................................................. 143

--program, <program>, -p <program>.......................................................................................... 143

--delay <seconds>, -d <seconds> ............................................................................................... 143

--scan, -s...................................................................................................................................... 143

Examples ............................................................................................................................................ 144

Viewing or Changing License Levels: bcadm --license........................................................................ 145

Syntax ................................................................................................................................................. 145

Options................................................................................................................................................ 145

--display, -d.................................................................................................................................. 145

--update <license_key>, -u <license_key> .................................................................................. 145

Example .............................................................................................................................................. 145

Retrieving and Updating the License Key........................................................................................... 146

Example bcadm Usage with Output ....................................................................................................... 147

Section 10: Compliance Information..............................................................................158

FCC Compliance Statement .................................................................................................................... 158

Industry Canada Compliance Statement ............................................................................................... 158

CE Compliance Information .................................................................................................................... 159

L'Information de Conformite de la CE ................................................................................................. 159

CE-befolgungInformationen ................................................................................................................ 159

Index..................................................................................................................................161

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LIST OF FIGURES

Figure 1: RAIDCore Hardware and Software Installation Process Flow......................................................... 14

Figure 2: BC4000 Series Controller Showing LED Connectors and Port Locations....................................... 15

Figure 3: BC4000 Series Controller Ports....................................................................................................... 16

Figure 4: LED Connector Pinout ..................................................................................................................... 17

Figure 5: BC4000 Series Cable Connection Between Controller and Hard Disk............................................ 18

Figure 6: The Array Status Window................................................................................................................ 65

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LIST OF TABLES

Table 1: Key to Number of Channels and Supported Functionality Level

Indicated by the BC4000 Series Model Number................................................................................ 7

Table 2: BC4000 Series License Levels.......................................................................................................... 9

Table 3: Feature List for Different License Levels of the BC4000 Series ...................................................... 10

Table 4: System Requirements ..................................................................................................................... 12

Table 5: Minimum Disks Required for Each RAID Level ............................................................................... 43

Table 6: Event Priority Levels ...................................................................................................................... 106

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Document BC4000-UM100-R Introduction Page 1

Section 1: Introduction

This manual describes the installation and operation of Broadcom’s RAIDCore™ BC4000 Series RAID

controllers, which includes HT-1000 controllers, as well as the use of RAIDCore XelCore™ RAID management

software.

AUDIENCE

The intended audience is system administrators and experienced users who are familiar with RAID and

storage configuration, and who also have a general understanding of one of the following operating systems:

• Microsoft Windows

®

• Linux

®

For specific supported versions of each operating system, see the list given on the Broadcom website at the

following web address:

http://www.broadcom.com/storage

.

OBTAINING ACROBAT

The documentation provided for the BC4000 Series RAID controllers is in the *.pdf Acrobat reader format. To

obtain the latest version of Acrobat from Adobe Systems, Inc., use the following web address:

http://www.adobe.com/products/acrobat/readermain.html

CONTACTING BROADCOM

You can contact Broadcom by phone, e-mail, or regular mail.

• Phone: 603-324-1555

• Web Address:

For more information about RAIDCore BC4000 Series RAID controllers:

http://www.broadcom.com/storage

• E-mail:

For service and support assistance: support@raidcore.com

For sales questions: sales@raidcore.com

For documentation feedback: documentation@raidcore.com

• Postal Address:

Broadcom Corporation, Inc.

71 Spit Brook Road, Suite 304

Nashua, NH 03060

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Page 2 Overview of RAID Concepts Document BC4000-UM100-R

Section 2: Overview of RAID Concepts

UNDERSTANDING ARRAYS

Disk arrays are several disks that are grouped together in various organizations to improve either the

performance or the reliability of a computer’s storage system. Because some array types enhance

performance while others improve reliability, and because some array types enhance both, it is important to

consider your needs when planning an array configuration.

The BC4000 Series RAID controller supports various array types. For small systems with four or less drives,

RAID1 and RAID5 are appropriate choices. For larger systems with more drives available, RAID10 and

RAID50 may be the appropriate choices. The unique ability of the RAIDCore controller to provide online

expansion to other array types such as RAID10 and RAID50 across multiple drives and controllers becomes

extremely valuable when expanding storage is a requirement.

OVERVIEW OF ARRAY TYPES

The BC4000 Series RAID controller supports the following Redundant Array of Independent Disk (RAID) array

types. Note that the list of supported array types is affected by a controller’s license level.

• Vol u me: The controller treats one or more disks or unused space on a disk as a single array. Volume

provides the ability to concatenate storage from various drives regardless of the size of the space on

those drives. Volume is useful in scavenging space on drives unused by other arrays. Volume does not

provide any performance or data redundancy benefit.

• RAID0: RAID0, or striping, provides the highest performance but no data redundancy. Data in the array is

striped (distributed) across several physical drives. RAID0 arrays are useful for holding information such

as the operating system paging file, where performance is extremely important but redundancy is not.

• RAID1: RAID1, or mirroring, mirrors data on a partition of one disk to another. RAID1 is useful when there

are only two disks available and data integrity is more important than storage capacity.

• RAID1n: RAID1n, or n-way mirroring, mirrors the data stored in one hard drive to several hard drives. This

array type provides superior data redundancy because there are three or more copies of the data, and is

useful for creating exact copies of an array for backup purposes. However, this array type is expensive, in

both performance and the amount of disk space necessary to create the array type.

• RAID10: RAID10 is also known as RAID(0+1) or striped mirror sets. This array type combines mirrors and

stripe sets. RAID10 allows multiple drive failures, up to 1 failure in each mirror that has been striped. This

array type offers better performance than a simple mirror because of the extra drives. RAID10 requires

twice the disk space of RAID0 to offer redundancy.

• RAID10n: RAID10n stripes multiple n-way mirror sets. RAID10n allows multiple drive failures per mirror

set, up to n-1 failures in each mirror set that has been striped, where n is the number of drives in each

mirror set. This array type is useful in creating exact copies of an array's data using the split command.

This array type offers better random read performance than a RAID10 array, but uses more disk space.

Note: It is highly recommended that you review this documentation in its entirety before configuring

arrays. Some of the advanced features of this controller (such as Online Capacity Expansion,

Online RAID Level Migration, sparing options) need to be understood by the user before arrays are

created.

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• RAID5: RAID5, also known as a stripe with parity, stripes data as well as parity across all drives in the

array. Parity information is interspersed across the drive array. In the event of a failure, the controller can

restore the lost data of the failed drive from the other surviving drives. This array type offers exceptional

read performance as well as redundancy. In general, write performance is not an issue due to the

tendency of operating systems to perform many more reads than writes. This array type requires only one

extra disk to offer redundancy. For most systems with four or more disks, this is the correct choice as array

type.

• RAID50: RAID50, also known as striped RAID5 sets, intersperses parity information across each RAID5

set in the array. This array type offers good read performance as well as redundancy. A 6-drive array

provides two striped 3-drive RAID5 sets. Generally, RAID50 is useful in very large arrays, arrays with 10 or

more disks. Like the RAID1n and RAID10n array types, RAID50 can handle multiple disk failures.

For the minimum disk requirements for each type of array, see “Expanding Disk Capacity Online” on page 3.

See also “Performance Considerations” on page 4 to learn how to maximize the performance of your arrays.

EXPANDING DISK CAPACITY ONLINE

Online capacity expansion (OCE) allows you to add any number of disks to an array at any time and continue

to access the array data while it is being redistributed.

To increase the size and organization of an array, transform the array. You can also use the transform function

as an integral part of the system backup and recover strategy through the use of the RAID1, RAID10, RAID1n,

and RAID10n array types. For more information on transforming arrays from RAIDConsole, see “Transforming

Arrays” on page 84. For more information on transforming arrays from bcadm, see “Transforming Arrays:

bcadm --transform” on page 134.

MIGRATING RAID LEVELS ONLINE

With Online RAID Level Migration (ORLM), you can easily move from one RAID level to another. While the

migration is taking place, the data is accessible and protected to the lowest protection of either the source RAID

level or the destination RAID level.

The transform feature can be used to increase the size and organization of an array. It can also be used as an

integral part of the system backup and recover strategy through the use of the RAID1, RAID10, RAID1n, and

RAID10n array types. To do this from RAIDConsole, see “Transforming Arrays” on page 84, and from bcadm,

see “Transforming Arrays: bcadm --transform” on page 134.

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Page 4 Performance Considerations Document BC4000-UM100-R

PERFORMANCE CONSIDERATIONS

One of the main advantages of using RAID is increased performance. With RAID, performance is based on

four elements: the number and organization of disks in an array, the caching attributes being used for the array,

the application workload, and the PCI bus speed.

• Spindles: RAID increases performance by putting more disks to work and by buffering data for the host.

Many disks can transfer data at greater than 50 MegaBytes per second, and the BC4000 Series RAID

controllers can aggregate this bandwidth in an almost linear fashion as more of the same drives are

included in an array.

• Caching: The BC4000 Series RAID controller software can also be configured to provide read- and write-

back caching, if desired. Write-back caching has a large effect on most workloads, but should be used

with caution.

• Workload: When configuring an array, workload is probably the most important performance variable.

Most applications do many more reads than writes, so the best performance will be obtained with array

types like RAID0, RAID10, and RAID5.

• PCI Bus Speed: Performance bottlenecks can be caused by the type of PCI bus you are using. The

maximum theoretical performance of a PCI 32-bit 33-MHz bus is 132 MegaBytes per second.

Performance increases to 512 MegaBytes per second with a PCI 64-bit 66-MHz bus.

The best possible performance with the fewest bottlenecks on PCI-X systems can be obtained by using a

PCI-X 64-bit 133-MHz bus, which offers 1024 MegaBytes per second.

RELIABILITY CONSIDERATIONS

Improved reliability is the other main argument for using RAID. Reliability is enhanced through data

redundancy and backup.

• Redundancy. RAID1, RAID10, RAID1n, RAID 10n. RAID5, or RAID50 are necessary for redundancy.

With redundancy, both capacity and performance are sacrificed for reliability. It should be noted, however,

that with the BC4000 Series RAID controllers, extremely high performance is obtained even with

redundant type arrays.

• Backup. The controller’s ability to transform arrays and split mirrors can be used as part of your backup

strategy. For example, you may want to create a RAID1 or RAID10 array and periodically transform these

into RAID1n and RAID10n arrays. These RAID1n and RAID10n arrays can then be split into the original

array and a backup array. As part of a hot fallback strategy, the backup array can be kept online and

hidden from the OS or remain visible, or it can be removed and stored as a backup device.

When a boot array is split, the original and the copy are exact copies with the same labels. This means that

when using the Linux operating system, Broadcom recommends that you keep the split copy hidden during

boot time to avoid boot-time issues with duplicate labels.

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Document BC4000-UM100-R Flexibility and Expansion Considerations Page 5

FLEXIBILITY AND EXPANSION CONSIDERATIONS

Before configuring an array, consider the following points to enhance the flexibility of your RAID system.

MULTIPLE TYPES

Most RAID controllers do not allow you to change a chosen array type, create more than one type of array for

each controller, or to create more than one array per physical disk. With the BC4000 Series RAID controller,

you can create different types of arrays on the same disk to adapt each array to the I/O that it processes.

Furthermore, depending on the array capacity and redundancy level, you can then transform an existing array

to another RAID type if the type of array you are using is not the optimal type for your application. You can also

build different arrays with different characteristics for different applications.

FUTURE EXPANSION

When creating arrays, consider whether you will need to expand your disk capacity in the future. If you

anticipate the need to expand a file system:

• On Windows, format your arrays with NTFS. Microsoft provides a utility (diskpart.exe) that will dynamically

extend an NTFS file system onto any unused adjacent space. Note also that using a single partition per

array will make expansion much easier. The diskpart.exe utility version you need depends on which

version of Windows you are running. The diskpart.exe utility can be found on the CD for some versions of

Windows or on the Microsoft website (www.microsoft.com) for others. Use the correct version for your

operating system.

• On Linux operating systems, be sure to use an expandable file system. Because the BC4000 Series

RAID controller is limited to eight arrays, if you need a large number of logical volumes, you may want to

use a logical volume manager, such as LVM.

OPERATING SYSTEM CONSIDERATIONS

One final and important array planning consideration is whether to extend the RAID benefits to your system

disk and operating system, as well as to your data disks. For example, if you install the operating system on a

RAID1 array (mirror), split the array into two volumes and then hide one of the resulting volumes, you can easily

recover your operating system should your system disk fail. Alternatively, you can improve operating system

performance by installing the OS on a RAID10 array and then splitting it and hiding one of the RAID0 arrays

(like a hot spare).

To install the operating system on an array and then boot from that array, see “Initializing Disks from the BIOS”

on page 51.

BC4000 Series RAID Controllers User Manual

02/13/06

Broadcom Corporation

Page 6 General Product Information Document BC4000-UM100-R

Section 3: General Product Information

OVERVIEW OF FEATURES

The RAIDCore BC4000 Series RAID controllers and XelCore™ software support various array types. For small

systems with four or less drives, RAID1 and RAID5 are appropriate choices. For larger systems with more

drives available, RAID10 and RAID50 may be the appropriate choices. The unique ability of the controller to

provide online expansion to other array types such as RAID10 and RAID50 across multiple drives and

controllers becomes extremely valuable when expanding storage is a requirement.

The licensing level that you purchase determines which set of features you receive.The list of enterprise-class

RAIDCore features available with the BC4000 Series RAID Controller includes:

• Online RAID Level Migration (ORLM): With online RAID level migration, users can easily move from one

RAID level to another. While the migration is taking place, the data is accessible and protected to the

lowest protection of either the source RAID level or the destination RAID level.

• Online Capacity Expansion (OCE): With online capacity expansion, users can have a maximum of 32

disks in an array at any time and continue to access their data while it is being redistributed.

• Controller Spanning: A unique feature that allows arrays to be created across controllers so that very

wide arrays can be created.

• Array Hiding: An array can be hidden from the operating system so neither software nor users can see or

access it. This is a key element in creating secure data backups.

• Mirror Splitting: A user can split a mirrored array so that the volumes can be worked with independently.

• Drive Roaming: With drive roaming, SATA cables can be disconnected from their drives and shuffled

without confusing the controller (this is performed offline). The controller detects which disks belong to

which arrays.

• Cache Support for Arrays: Various array-caching options are supported: read, read with write-back,

write-back, and no cache.

• Cache Support for Disks: Various disk-caching options are supported: no cache, disk read ahead +

write-back, disk read ahead, and disk write-back.

• Background Array Initialization: Background initialization allows a redundant array to be used

immediately. If a disk is lost prior to completion of the create, no data is lost.

• Sparing Support: For enhanced data integrity, several types of disk sparing are supported: distributed,

dedicated, and global sparing.

• Multiple Array Types Per Drive: Support for multiple array types per drive allows the administrator to

create different array types using the same disks.

• SMART: Self-Monitoring Analysis and Reporting Technology is a set of advanced diagnostics that monitor

the internal operations of disk drives and provide early warning of any potential problems.

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