EMC FC5300 User's Manual

EMC Enterprise Storage

EMC Fibre Channel Storage Systems

Models FC4500, FC5300, and FC5700

CONFIGURATION PLANNING GUIDE

P/N 014003039-02

EMC Corporation

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ii

EMC Fibre Channel Storage Systems Configuration Planning Guide

Contents

Preface

..............................................................................................................................xi

Chapter 1 About Fibre Channel Storage Systems and Networks

(SANs)

Introducing EMC Fibre Channel Storage Systems.......................1-2

Fibre Channel Background..............................................................1-3

Fibre Channel Storage Components ..............................................1-4

Server Component (Host-Bus Adapter Driver Package with

Software) .....................................................................................1-4

Interconnect Components ........................................................1-4

Storage Component (Storage Systems, Storage Processors

(SPs), and Other Hardware).....................................................1-9

Types of Storage System Installations..........................................1-10

About Switched Shared Storage and SANs (Storage Area

Networks) ........................................................................................1-11

Storage Groups.........................................................................1-12

Storage System Hardware for Shared Storage ....................1-15

About Unshared Storage ...............................................................1-16

Storage System Hardware for Unshared Storage ...............1-16

Chapter 2 RAID Types and Tradeoffs

Introducing RAID .............................................................................2-2

Disk Striping...............................................................................2-2

Mirroring.....................................................................................2-2

RAID Groups and LUNs ..........................................................2-3

RAID Types........................................................................................2-4

RAID 5 Group (Individual Access Array) .............................2-4

RAID 3 Group (Parallel Access Array)...................................2-5


iii

Contents

Chapter 3

Chapter 4

Chapter 5

RAID 1 Mirrored Pair ...............................................................2-7

RAID 0 Group (Nonredundant Array) ..................................2-8

RAID 1/0 Group (Mirrored RAID 0 Group) .........................2-8

Individual Disk Unit .................................................................2-9

Hot Spare ....................................................................................2-9

RAID Benefits and Tradeoffs.........................................................2-12

Performance .............................................................................2-13

Storage Flexibility ....................................................................2-14

Data Availability and Disk Space Usage..............................2-14

Guidelines for RAID Types ...........................................................2-17

Sample Applications for RAID Types..........................................2-19

Planning File Systems and LUNs with Shared Switched

Storage

Dual Paths to LUNs..........................................................................3-2

Sample Shared Switched Installation ............................................3-3

Planning Applications, LUNs, and Storage Groups....................3-6

Application and LUN Planning ..............................................3-6

Application and LUN Planning Worksheet ..........................3-7

LUN and Storage Group Planning Worksheet .....................3-8

LUN Details Worksheet..........................................................3-11

Planning LUNs and File Systems with Unshared Direct

Storage

Dual SPs and Paths to LUNs...........................................................4-2

Unshared Direct and Shared-or-Clustered Direct Storage .........4-2

Sample Unshared Direct Installation......................................4-2

Sample Shared-or-Clustered Direct Installation ...................4-3

Planning Applications and LUNs ..................................................4-4

Application and LUN Planning ..............................................4-4

Application and LUN Planning Worksheet ..........................4-5

LUN Planning Worksheet ........................................................4-6

Completing the LUN Details Worksheet .............................4-12

Storage System Hardware

Hardware for Shared Storage .........................................................5-3

Storage Hardware — Rackmount DPE-Based Storage

Systems .......................................................................................5-3

Disks ............................................................................................5-4

Storage Processor (SP) ..............................................................5-5

iv


Contents

Chapter 6

Hardware for Unshared Storage.................................................... 5-6

Types of Storage System for Unshared Storage ................... 5-6

Disks............................................................................................ 5-8

Storage Processor (SP) .............................................................. 5-9

Planning Your Hardware Components ...................................... 5-11

Configuration Tradeoffs - Shared Storage .......................... 5-11

Configuration Tradeoffs - Unshared Storage ..................... 5-12

Hardware Data Sheets ................................................................... 5-14

DPE Data Sheet........................................................................ 5-14

iDAE Data Sheet...................................................................... 5-16

DAE Data Sheet....................................................................... 5-18

Cabinets for Rackmount Enclosures............................................ 5-20

Cable and Configuration Guidelines .......................................... 5-21

Hardware Planning Worksheets .................................................. 5-24

Hardware for Shared Storage ............................................... 5-24

Hardware Component Worksheet for Shared Storage...... 5-25

Hardware Component Worksheet for Shared Storage...... 5-27

Hardware for Unshared Storage .......................................... 5-27

Hardware Component Worksheet for Unshared Storage. 5-30




Storage-System Management

Using Navisphere Manager Software ........................................... 6-3

Storage Management Worksheets.................................................. 6-5

Index

................................................................................................................................ i-1


v

Contents vi


Figures

5-2

5-3

5-4

5-5

5-6

5-7

3-1

4-1

4-2

5-1

2-4

2-5

2-6

2-7

1-9

1-10

1-11

1-12

1-13

2-1

2-2

2-3

1-5

1-6

1-7

1-8

1-1

1-2

1-3

1-4

Storage System Models ................................................................................ 1-2

Nodes - Initiator and Target ....................................................................... 1-3

Switch and Hub Topologies Compared .................................................... 1-6

A Switch Zone ............................................................................................... 1-7

16-Port Switch, Back View .......................................................................... 1-7

Nine-Port Hub .............................................................................................. 1-8

Disk-Array Processor Enclosure (DPE) ..................................................... 1-9

Types of Storage System Installation ....................................................... 1-10

Components of a SAN ............................................................................... 1-11

Sample SAN Configuration ...................................................................... 1-13

Data and Configuration Access Control with Shared Storage ............ 1-14

Storage System with a DPE and Three DAEs ........................................ 1-15

Storage System Hardware for Unshared Storage .................................. 1-17

Multiple LUNs in a RAID Group ............................................................... 2-3

RAID 5 Group ............................................................................................... 2-5

RAID 3 Group ............................................................................................... 2-6

RAID 1 Mirrored Pair .................................................................................. 2-7

RAID 1/0 Group (Mirrored RAID 0 Group) ............................................ 2-9

How a Hot Spare Works ............................................................................ 2-11

Disk Space Usage in the RAID Configurations ...................................... 2-16

Sample Shared Switched High Availability installation ........................ 3-3

Unshared Direct Installation ....................................................................... 4-2

Sample Clustered Installation ..................................................................... 4-3

Shared and Unshared Storage .................................................................... 5-2

DPE Storage-System Components – Rackmount Model ........................ 5-3

Rackmount System with DPE and DAEs .................................................. 5-4

Shared Storage Systems ............................................................................... 5-5

Storage System Types for Unshared Storage ........................................... 5-7

DPE Components - Deskside Model ......................................................... 5-8

Disks and Disk IDs ....................................................................................... 5-9

EMC Fibre Channel Storage-System Configuration Planning Guide vii

Figures

5-8

5-9

5-10

5-11

5-12

5-13

5-14

5-15

5-16

5-17

6-1

6-2

Storage System with Two SPs Connected to the Same Server ............. 5-10

Storage System with Two SPs Connected to Different Servers ............ 5-10

Comparison Between Optical and Copper Cabling ............................... 5-21

Cable Identifier — DPE-Based System for Shared Storage ................... 5-24

Sample Shared Storage Installation .......................................................... 5-26

Cable Identifier — Unshared System without Hubs ............................. 5-28

Cable Identifier — Unshared Full-Fibre System with Hubs ................. 5-29

Sample Unshared Deskside System — Basic Configuration ................ 5-31

Sample Unshared Deskside System — Dual-Adapter/Dual-SP

Configuration ............................................................................................... 5-32

Sample Component Worksheet for DPE-Based System with Hubs — Two

Loops.............................................................................................................. 5-34

Sample Shared Switched Environment with Navisphere Manager ...... 6-4

Sample Unshared Environment with Navisphere Manager .................. 6-4

viii EMC Fibre Channel Storage-System Configuration Planning Guide

Tables

2-1

3-1

4-1

5-1

5-2

5-3

5-4

Performance, Availability, and Cost of RAID Types

(Individual Unit = 1.0) ............................................................................... 2-13

Cache Recommendations for Different RAID Types ............................ 3-16

Cache Recommendations for Different RAID Types ............................ 4-15

High-Availability Options, Deskside Unshared Storage ...................... 5-13

High-Availability Options, Rackmount Unshared Storage ................. 5-13

Cable Sizes — Optical ............................................................................ 5-22

Cable Sizes — Copper ................................................................................ 5-23

EMC Fibre Channel Storage-System Configuration Planning Guide ix

Tables x EMC Fibre Channel Storage-System Configuration Planning Guide

Preface

This planning guide provides an overview of Fibre Channel disk-array storage-system models and offers essential background information and worksheets to help you with the installation and configuration planning.

Please read this guide

• if you are considering purchase of an EMC Fibre Channel disk-array storage system and want to understand its features; or

• before you plan the installation of a storage system.

Audience for the Manual

You should be familiar with the host servers that will use the storage systems and with the operating systems of the servers. After reading this guide, you will be able to

• determine the best storage system components for your installation

• determine your site requirements

• configure storage systems correctly

EMC Fibre Channel Storage-System Configuration Planning Guidexi xi

Preface

Organization of the Manual

Chapter 1

Chapter 2

Chapter 3

Chapter 4

Chapter 5

Chapter 6

Provides background information on the Fibre

Channel protocols and explains the major installation types.

Describes the RAID Groups and the different ways they store data.

Describes installations for shared switched storage.

Describes installations for unshared direct, and shared-or-clustered direct, and shared switched storage.

Describes hardware components.

Describes storage-system management utilities.

xii EMC Fibre Channel Storage-System Configuration Planning Guide

1

About Fibre Channel

Storage Systems and

Networks (SANs)

This chapter introduces Fibre Channel disk-array storage systems and storage area networks (SANs). Major sections are

• Introducing EMC Fibre Channel Storage Systems........................1-2

• Fibre Channel Background ...............................................................1-3

• Fibre Channel Storage Components................................................1-4

• About Switched Shared Storage and SANs (Storage Area

Networks).......................................................................................... 1-11

• About Unshared Storage.................................................................1-16

About Fibre Channel Storage Systems and Networks (SANs) 1-1

1

About Fibre Channel Storage Systems and Networks (SANs)

Introducing EMC Fibre Channel Storage Systems

EMC Fibre Channel disk-array storage systems provide terabytes of disk storage capacity, high transfer rates, flexible configurations, and highly available data at low cost.

A storage system package includes a host-bus adapter driver package with hardware and software to connect with a server, storage management software, Fibre Channel interconnect hardware, and one or more storage systems.

Figure 1-1 Storage System Models

1-2 EMC Fibre Channel Storage-System Configuration Planning


1

Fibre Channel Background

Fibre Channel is a high-performance serial protocol that allows transmission of both network and I/O channel data. It is a low level protocol, independent of data types, and supports such formats as

SCSI and IP.

The Fibre Channel standard supports several physical topologies, including switched fabric point-to-point and arbitrated loop (FC-AL).

The topologies used by the Fibre Channel storage systems described in this manual are switched fabric and FC-AL.

A switch fabric is a set of point-to-point connections between nodes, the connection being made through one or more Fibre Channel switches. Each node may have its own unique address, but the path between nodes is governed by a switch. The nodes are connected by optical cable.

A Fibre Channel arbitrated loop is a circuit consisting of nodes. Each node has a unique address, called a Fibre Channel arbitrated loop address. The nodes are connected by optical cables. An optical cable can transmit data over great distances for connections that span entire enterprises and can support remote disaster recovery systems.

Copper cable serves well for local connections; its length is limited to

30 meters (99 feet).

Each connected device in a switched fabric or arbitrated loop is a server adapter (initiator) or a target (storage system). The switches and hubs are not considered nodes.

Server Adapter (initiator)

Node

Connection

Storage System (target)

Node

EMC1802

Figure 1-2 Nodes - Initiator and Target

Fibre Channel Background 1-3

1


Fibre Channel Storage Components

A Fibre Channel storage system has three main components:

• Server component (host-bus adapter driver package with adapter and software)

• Interconnect components (cables based on Fibre Channel standards, switches, and hubs)

• Storage components (storage system with storage processors —

SPs — and power supply and cooling hardware)

Server Component (Host-Bus Adapter Driver Package with Software)

The host-bus adapter driver package includes a host-bus adapter and support software. The adapter is a printed-circuit board that slides into an I/O slot in the server’s cabinet. It transfers data between server memory and one or more disk-array storage systems over

Fibre Channel — as controlled by the support software (adapter driver).

One or more servers can use a storage system. For high availability — in event of an adapter failure — a server can have two adapters.

Server

EMC1803

Depending on your server type, you may have a choice of adapters.

The adapter is designed for a specific host bus; for example, a PCI bus or SBUS. Some adapter types support copper or optical cabling; some support copper cabling only.

Interconnect Components

The interconnect components include the cables, Fibre Channel switch (for shared storage), and Fibre Channel hub (for unshared storage).

Cables Depending on your needs, you can choose copper or optical cables.



1

The maximum length of copper cable is 30 meters (99 feet) between nodes or hubs. The maximum length of optical cable between server and hub or storage system is much greater, depending on the cable type. For example, 62.5-micron multimode cable can span up to 500 meters (1,640 feet) while 9-micron single-mode cable can span up to

10 kilometers (6.2 miles). This ability to span great distances is a major advantage of optical cable.

Some nodes have connections that require a specific type of cable: copper or optical. Other nodes allow for the conversion from copper to optical using a conversion device called a GigaBit Interface

Converter (GBIC) or Media Interface Adapter (MIA). In most cases, a

GBIC or MIA lets you substitute long-distance optical connections for shorter copper connections.

With extenders, optical cable can span up to 40 km (25 miles). This ability to span great distances is a major advantage of optical cable.

Details on cable lengths and rules appear later in this manual.

Fibre Channel Switches

A Fibre Channel switch, which is a requirement for shared storage (a

Storage Area Network, SAN) connects all the nodes cabled to it using a fabric topology. A switch adds serviceability and scalability to any installation; it allows on-line insertion and removal of any device on the fabric and maintains integrity if any connected device stops participating. A switch also provides host-to-storage-system access control in a multiple-host shared-storage environment. A switch has several advantages over a hub: it provides point-to-point connections

(as opposed to a hub’s loop that includes all nodes) and it offers zoning to specify paths between nodes in the switch itself.

Fibre Channel Storage Components 1-5

1


You can cascade switches (connect one switch port to another switch) for additional port connections.

Switch topology (point-to-point)

Server Server Server

Server

Hub topology (loop)

Server

Server

Switch uses discrete connections between ports

Hub uses loop between ports

SP SP SP

Storage systems

SP

To illustrate the comparison, this figure shows just one adapter per server and one switch or hub. Normally, such installations include two adapters per server and two switches or hubs.

Figure 1-3 Switch and Hub Topologies Compared

Switch Zoning

Switch zoning defines paths between connected nodes. Each zone encloses one or more adapters and one or more SPs. A switch can have as many zones as it has ports. The current connection limits are four SP ports to one adapter port (the SPs fan in to the adapter) and

15 adapters to one SP (the SPs fan out to the adapters). There are several zone types, including the single-initiator type, which is the recommended type.

In the following figure, Server 1 has access to one SP (SP A) in storage systems 1 and 2; it has no access to any other SP.



1

Server 1

Switch fabric

Zone

SP SP SP SP SP SP

Storage system 1 Storage system 2 Storage system 3

To illustrate switch zoning, this figure shows just one HBA per server and one switch or hub. Normally, such installations will include two HBAs per server and two switches or hubs.

Figure 1-4 A Switch Zone

If you do not define a zone in a switch, all adapter ports connected to the switch can communicate with all SP ports connected to the switch. However, access to an SP does not necessarily provide access to the SP’s storage; access to storage is governed by the Storage

Groups you create (defined later).

Fibre Channel switches are available with 16 or 8 ports. They are compact units that fit in 2 U (3.5 inches) for the 16-port or 1 U (1.75 inches) for the 8-port. They are available to fit into a rackmount cabinet or as small deskside enclosures.

Ports

Figure 1-5 16-Port Switch, Back View

EMC1807


1


Fibre Channel Hubs

If your servers and storage systems will be far apart, you can place the switches closer to the servers or the storage systems, as convenient.

A switch is technically a repeater, not a node, in a Fibre Channel loop.

However, it is bound by the same cabling distance rules as a node.

A hub connects all the nodes cabled to it into a single logical loop. A hub adds serviceability and scalability to any loop; it allows on-line insertion and removal of any device on the loop and maintains loop integrity if any connected device stops participating.

Fibre channel hubs are compact units that fit in 1 U (1.75 inches) of storage space. They are available to fit into a rackmount cabinet or as small deskside units.

The nine-pin port can connect to a server, storage system, or another hub.

Figure 1-6 Nine-Port Hub

If your servers and storage systems will be far apart, you can place the hubs closer to the servers or the storage systems, as convenient.



1

Storage Component (Storage Systems, Storage Processors (SPs), and Other

Hardware)

EMC disk-array storage systems, with their storage processors, power supplies, and cooling hardware form the storage component of a Fibre Channel system. The controlling unit, a Disk-array

Processor Enclosure (DPE) looks like the following figure.

Disk modules

EMC1808

Figure 1-7 Disk-Array Processor Enclosure (DPE)

DPE hardware details appear in a later chapter.


1


Types of Storage System Installations

Unshared Direct

(one or two servers)

Server

You can use a storage systems in any of several types of installation:

• Unshared direct with one server is the simplest and least costly;

• Shared-or-clustered direct lets two clustered servers share storage resources with high availability (FC4500 storage systems; and

• Shared switched , with one or two switch fabrics, lets two to 15 servers share the resources of several storage systems in a Storage

Area Network (SAN) Shared switched installations are available in a high-availability (HA) version, with two HBAs per server, with two switches, or with one HBA per server and one switch.

Shared-or-Clustered Direct

(two servers)

Server Server

Shared Switched

(multiple servers)

Server Server

Server

Switch fabric Switch fabric

Path 1

Path 2

Disk-array storage systems

Figure 1-8 Types of Storage System Installation

Storage systems for any shared installation require EMC Access

Logix™ software to control server access to the storage system LUNs.

The Shared-or-clustered direct installation may be either shared (that is, use Access Logix to control LUN access) or clustered (without

Access Logix, using cluster software to control LUN access), depending on the hardware model.



1

About Switched Shared Storage and SANs (Storage Area

Networks)

This section explains the features that let multiple servers share disk-array storage systems on a SAN (storage area network).

A SAN is a collection of storage devices connected to servers via Fibre

Channel switches to provide a central location for disk storage.

Centralizing disk storage among multiple servers has many advantages, including

• highly available data

• flexible association between servers and storage capacity

• centralized management for fast, effective response to users’ data storage needs

• easier file backup and recovery

An EMC SAN is based on shared storage; that is, the SAN requires the Access Logix option to provides flexible access control to storage system LUNs.

Server Server Server

Switch fabric

SP A SP B

Storage systems

Switch fabric

SP A SP B

Path 1

Path 2

Figure 1-9 Components of a SAN

Fibre Channel switches can control data access to storage systems through the use of switch zoning. With zoning, an administrator can specify groups (called zones) of Fibre Channel devices (such as host-bus adapters, specified by worldwide name), and SPs between which the switch will allow communication.

About Switched Shared Storage and SANs (Storage Area Networks) 1-11

1


Storage Groups

However, switch zoning cannot selectively control data access to

LUNs in a storage system, because each SP appears as a single Fibre

Channel device to the switch. So switch zoning can prevent or allow communication with an SP, but not with specific disks or LUNs attached to an SP. For access control with LUNs, a different solution is required: Storage Groups.

A Storage Group is one or more LUNs (logical units) within a storage system that is reserved for one or more servers and is inaccessible to other servers. Storage Groups are the central component of shared storage; storage systems that are unshared do not use Storage

Groups.

When you configure shared storage, you specify servers and the

Storage Group(s) each server can read from and/or write to. The Base

Software firmware running in each storage system enforces the server-to-Storage Group permissions.

A Storage Group can be accessed by more than one server if all the servers run cluster software. The cluster software enforces orderly access to the shared Storage Group LUNs.

The following figure shows a simple shared storage configuration consisting of one storage system with two Storage Groups. One

Storage Group serves a cluster of two servers running the same operating system, and the other Storage Group serves a UNIX database server. Each server is configured with two independent paths to its data, including separate host-bus adapters, switches, and

SPs, so there is no single point of failure for access to its data.



1

Highly available cluster

File Server

Operating system A

Mail Server

Operating system A

Database Server

Operating system B


Cluster

Storage Group

Database Server

Storage Group

SP A

LUN

LUN

LUN

LUN

LUN

LUN

LUN

SP B

Physical storage systems with up to

100 disks per storage system

Path 1

Path 2

Figure 1-10 Sample SAN Configuration

Access Control with Shared Storage

Access control permits or restricts a server’s access to shared storage.

There are two kinds of access control:

• Configuration access control

• Data access control

Configuration access control lets you restrict the servers through which a user can send configuration commands to an attached storage system.

Data access control is provided by Storage Groups. During storage system configuration, using a management utility, the system administrator associates a server with one or more LUNs.

Each server sees its Storage Group as if it were an entire storage system, and never sees the other LUNs on the storage system.

Therefore, it cannot access or modify data on LUNs that are not part of its Storage Group. However, you can define a Storage Group to be accessible by more than one server, if, as shown above, the servers run cluster software.


1


The following figure shows both data access control (Storage Groups) and configuration access control. Each server has exclusive read and write access to its designated Storage Group. Of the four servers connected to the SAN, only the Admin server can send configuration commands to the storage system.


Admin server

Operating system A

Inventory server E-mail server

Operating system A

Operating system B

Web server

Operating system B

01

02 03 04 05 06 07 08

Switch fabric

Switch fabric

Admin Storage Group

Dedicated

Data access by adapters 01, 02

Inventory Storage Group

Dedicated

Data access by adapters 03, 04

E-mail and Web server

Storage Group

Shared

Data access by

adapters 05, 06, 07, 08

SP A

LUN

LUN

LUN

LUN

LUN

LUN

LUN

LUN

LUN

LUN

SP B

Configuation access, by adapters 01and 02

(Admin server only)

Figure 1-11 Data and Configuration Access Control with Shared Storage



1

Storage System Hardware for Shared Storage

For shared storage, you need a Disk-array Processor Enclosure (DPE) storage system.

A DPE is a 10-slot enclosure with hardware RAID features provided by one or two storage processors (SPs). For shared storage, two SPs are required. In addition to its own disks, a DPE can support up to nine 10-slot Disk Array Enclosures (DAEs) for a total of 100 disks.

DAE

DAE

DAE

DPE

Standby power supply (SPS)

Figure 1-12 Storage System with a DPE and Three DAEs

EMC1741


1


About Unshared Storage

Unshared storage systems are less costly and less complex than shared storage systems. They offer many shared storage system features; for example, you can use multiple unshared storage systems with multiple servers. However, with multiple servers, unshared storage offers less flexibility and security than shared storage, since any user with write access to a privileged server’s files can enable access to any storage system.

Storage System Hardware for Unshared Storage

For unshared storage, there are four types of storage system, each using the FC-AL protocol. Each type is available in a rackmount or deskside (office) version.

• Disk-array Processor Enclosure (DPE) storage systems. A DPE is a 10-slot enclosure with hardware RAID features provided by one or two storage processors (SPs). In addition to its own disks, a

DPE can support up to 110 additional disks in 10-slot Disk Array

Enclosures (DAEs) for a total of 120 disks. This is the same type of storage system used for shared storage, but it has a different SP and different Core Software.

• Intelligent Disk Array Enclosure (iDAE). An iDAE, like a DPE, has SPs and thus all the features of a DPE, but is thinner and has a limit of 30 disks.

• Disk Array Enclosure (DAE). A DAE does not have SPs. A DAE can connect to a DPE or an iDAE, or you can use it without SPs. A

DAE used without an SP does not inherently include RAID, but can operate as a RAID device using software running on the server system. Such a DAE is also known as Just a Box of Disks, or

JBOD.



1

Disk-array processor enclosure (DPE)

Deskside DPE with DAE

Rackmount DPE, one enclosure, supports up to 9 DAEs

30-slot deskside

Intelligent disk-array enclosure (iDAE)

10-slot deskside Rackmount

Figure 1-13 Storage System Hardware for Unshared Storage

What Next?

For information about RAID types and RAID tradeoffs, continue to the next chapter. To plan LUNs and file systems for shared storage,

skip to Chapter 3; or for unshared storage, Chapter 4. For details on

the storage-system hardware — shared and unshared — skip to

Chapter 5. For storage-system management utilities, skip to

Chapter 6.

About Unshared Storage 1-17

1



2

RAID Types and

Tradeoffs

This chapter explains RAID types you can choose for your storage system LUNs. If you already know about RAID types and know which ones you want, you can skip this background information and

skip to Chapter 5. Topics are

• Introducing RAID ..............................................................................2-2

• RAID Types .........................................................................................2-4

• RAID Benefits and Tradeoffs ..........................................................2-12

• Guidelines for RAID Types.............................................................2-17

• Sample Applications for RAID Types ...........................................2-19

This chapter applies primarily to storage systems with storage processors

(SPs). For a storage system without SPs (a DAE-only or JBOD system), RAID types are limited by the RAID software you run on the server. The RAID terms and definitions used here conform to generally accepted standards.

RAID Types and Tradeoffs 2-1

2

RAID Types and Tradeoffs

Introducing RAID

Disk Striping

Mirroring

The storage system uses RAID (redundant array of independent disks) technology. RAID technology groups separate disks into one logical unit (LUN) to improve reliability and/or performance.

The storage system supports five RAID levels and two other disk configurations, the individual unit and the hot spare (global spare).

You group the disks into one RAID Group by binding them using a storage-system management utility.

Four of the RAID types use disk striping and two use mirroring.

Using disk stripes, the storage-system hardware can read from and write to multiple disks simultaneously and independently. By allowing several read/write heads to work on the same task at once, disk striping can enhance performance. The amount of information read from or written to each disk makes up the stripe element size.

The stripe size is the stripe element size multiplied by the number of disks in a group. For example, assume a stripe element size of 128 sectors (the default) and a five-disk group. The group has five disks, so you would multiply five by the stripe element size of 128 to yield a stripe size of 640 sectors.

The storage system uses disk striping with most RAID types.

Mirroring maintains a second (and optionally through software, a third) copy of a logical disk image that provides continuous access if the original image becomes inaccessible. The system and user applications continue running on the good image without interruption. There are two kinds of mirroring: hardware mirroring, in which the SP synchronizes the disk images; and software mirroring, in which the operating system synchronizes the images.

Software mirroring consumes server resources, since the operating system must mirror the images, and has no offsetting advantages; we mention it here only for historical completeness.

With a storage system, you can create a hardware mirror by binding disks as a RAID 1 mirrored pair or a RAID 1/0 Group (a mirrored

RAID 0 Group); the hardware will then mirror the disks automatically.



2

RAID Groups and

LUNs

Some RAID types let you create multiple LUNs on one RAID Group.

You can then allot each LUN to a different user, server, or application.

For example, a five-disk RAID 5 Group that uses 36-Gbyte disks offers 144 Gbytes of space. You could bind three LUNs, say with 24,

60, and 60 Gbytes of storage capacity, for temporary, mail, and customer files.

One disadvantage of multiple LUNs on a RAID Group is that I/O to each LUN may affect I/O to the others in the group; that is, if traffic to one LUN is very heavy, I/O performance with other LUNs may degrade. The main advantage of multiple LUNs per RAID Group is the ability to divide the enormous amount of disk space provided by

RAID Groups on newer, high-capacity disks.

RAID Group

LUN 0 temp

LUN 1 mail

LUN 2 customers

Disk

LUN 0 temp

LUN 1 mail

LUN 2 customers

Disk

LUN 0 temp

LUN 1 mail

LUN 2 customers

Disk

LUN 0 temp

LUN 1 mail

LUN 2 customers

Disk

LUN 0 temp

LUN 1 mail

LUN 2 customers

Disk

EMC1814

Figure 2-1 Multiple LUNs in a RAID Group

Introducing RAID 2-3

2


RAID Types

You can choose from the following RAID types: RAID 5, RAID 3,

RAID 1, RAID 0, RAID 1/0, individual disk unit, and hot spare.

RAID 5 Group (Individual Access Array)

A RAID 5 Group usually consists of five disks (but can have three to sixteen). A RAID 5 Group uses disk striping. With a RAID 5 Group on a full-fibre storage system, you can create up to 32 RAID 5 LUNs to apportion disk space to different users, servers, and applications.

The storage system writes parity information that lets the group continue operating if a disk fails. When you replace the failed disk, the SP rebuilds the group using the information stored on the working disks. Performance is degraded while the SP rebuilds the group. However, the storage system continues to function and gives users access to all data, including data stored on the failed disk.

The following figure shows user and parity data with the default stripe element size of 128 sectors (65,536 bytes) in a five-disk RAID 5

Group. The stripe size comprises all stripe elements. Notice that the disk block addresses in the stripe proceed sequentially from the first disk to the second, third, and fourth, then back to the first, and so on.



2

Stripe element size

Stripe

Blocks

0-127

First disk

512-639 1024-11511536-1663 Parity

…

Second disk

128-255 640-767 1152-1279 Parity 2048-2175

…

Stripe size

256-383 768-895

Third disk

Parity 1664-1791 2176-2303

…

384-511 Parity

Fourth disk

1280-1407 1792-1919 2304-2431

…

User data

Parity data

Parity

Fifth disk

896-1023 1408-1535 1920-2047 2432-2559

…

EMC1815

Figure 2-2 RAID 5 Group

RAID 5 Groups offer excellent read performance and good write performance. Write performance benefits greatly from storage-system caching.

RAID 3 Group (Parallel Access Array)

A RAID 3 Group consists of five or more disks. The hardware always reads from or writes to all the disks. A RAID 3 Group uses disk striping. To maintain the RAID 3 performance, you can create only one LUN per RAID 3 Group.

The storage system writes parity information that lets the group continue operating if a disk fails. When you replace the failed disk, the SP rebuilds the group using the information stored on the working disks. Performance is degraded while the SP rebuilds the group. However, the storage system continues to function and gives users access to all data, including data stored on the failed disk.

RAID Types 2-5

2


The following figure shows user and parity data with a data block size of 2 Kbytes in a RAID 3 Group. Notice that the byte addresses proceed from the first disk to the second, third, and fourth, then the first, and so on.

Stripe size

Stripe element size

Data block

Bytes

0-511

First disk

2048-2559 4096-4607 6144-6655 8192-8603

…

Second disk

512-1023 2560-3071 4608-5119 6656-7167 8604-9115

…

Third disk

1024-1535 3072-3583 5120-5631 7168-7679 9116-9627

…

1536-2047

Fourth disk

3584-4095 5632-6143 7680-8191 9628-10139

…

Parity Parity

Fifth disk

Parity Parity Parity

…

User data

Parity data

EMC1816

Figure 2-3 RAID 3 Group

RAID 3 differs from RAID 5 in several important ways. First, in a

RAID 3 Group the hardware processes disk requests serially; whereas in a RAID 5 Group the hardware can interleave disk requests. Second, with a RAID 3 Group, the parity information is stored on one disk; with a RAID 5 Group, it is stored on all disks. Finally, with a RAID 3

Group, the I/O occurs in small units (one sector) to each disk. A

RAID 3 Group works well for single-task applications that use I/Os of blocks larger than 64 Kbytes.

Each RAID 3 Group requires some dedicated SP memory (6 Mbytes recommended per group). This memory is allocated when you create the group and becomes unavailable for storage-system caching. For top performance, we suggest that you do not use RAID 3 Groups with RAID 5, RAID 1/0, or RAID 0 Groups, since SP processing power and memory are best devoted to the RAID 3 Groups. RAID 1 mirrored pairs and individual units require less SP processing power, and therefore work well with RAID 3 Groups.



2

RAID 1 Mirrored Pair

For each write to a RAID 3 Group, the storage system

1. Calculates the parity data.

2. Writes the new user and parity data.

A RAID 1 Group consists of two disks that are mirrored automatically by the storage-system hardware.

RAID 1 hardware mirroring within the storage system is not the same as software mirroring or hardware mirroring for other kinds of disks.

Functionally, the difference is that you cannot manually stop mirroring on a RAID 1 mirrored pair, and then access one of the images independently. If you want to use one of the disks in such a mirror separately, you must unbind the mirror (losing all data on it), rebind the disk in as the type you want, and software format the newly bound LUN.

With a storage system, RAID 1 hardware mirroring has the following advantages:

• automatic operation (you do not have to issue commands to initiate it)

• physical duplication of images

• a rebuild period that you can select during which the SP recreates the second image after a failure

With a RAID 1 mirrored pair, the storage system writes the same data to both disks, as follows.

0

0

1

First disk

2 3

1

Second disk

2 3

4

…

4

…

User data

EMC1817

Figure 2-4 RAID 1 Mirrored Pair

RAID Types 2-7

2


RAID 0 Group (Nonredundant Array)

A RAID 0 Group consists of three to a maximum of sixteen disks. A

RAID 0 Group uses disk striping, in which the hardware writes to or reads from multiple disks simultaneously. In a full-fibre storage system, you can create up to 32 LUNs per RAID Group.

Unlike the other RAID levels, with RAID 0 the hardware does not maintain parity information on any disk; this type of group has no inherent data redundancy. RAID 0 offers enhanced performance through simultaneous I/O to different disks.

If the operating system supports software mirroring, you can use software mirroring with the RAID 0 Group to provide high availability. A desirable alternative to RAID 0 is RAID 1/0.

RAID 1/0 Group (Mirrored RAID 0 Group)

A RAID 1/0 Group consists of four, six, eight, ten, twelve, fourteen, or sixteen disks. These disks make up two mirror images, with each image including two to eight disks. The hardware automatically mirrors the disks. A RAID 1/0 Group uses disk striping. It combines the speed advantage of RAID 0 with the redundancy advantage of mirroring. With a RAID 1/0 Group on a full-fibre storage system, you can create up to 32 RAID 5 LUNs to apportion disk space to different users, servers, and applications.

The following figure shows the distribution of user data with the default stripe element size of 128 sectors (65,536 bytes) in a six-disk

RAID 1/0 Group. Notice that the disk block addresses in the stripe proceed sequentially from the first mirrored disks (first and fourth disks) to the second mirrored disks (second and fifth disks), to the third mirrored disks (third and sixth disks), and then from the first mirrored disks, and so on.



2

Stripe size

Stripe element size

Stripe

Blocks

0-127

First disk of primary image

384-511 768-895 1152-1279 1536-1663

…

128-255

Second disk of primary image

512-639 896-1023 1280-1407 1664-1791

…

256-383

Third disk of primary image

640-767 1024-1151 1408-1535 1792-1919

…

0-127

First disk of secondary image

384-511 768-895 1152-1279 1536-1663

…

128-255

Second disk of secondary image

512-639 896-1023 1280-1407 1664-1791

…

256-383

Third disk of secondary image

640-767 1024-1151 1408-1535 1792-1919

…

User data

EMC1818

Hot Spare

Figure 2-5 RAID 1/0 Group (Mirrored RAID 0 Group)

A RAID 1/0 Group can survive the failure of multiple disks, providing that one disk in each image pair survives.

Individual Disk Unit

An individual disk unit is a disk bound to be independent of any other disk in the cabinet. An individual unit has no inherent high availability, but you can make it highly available by using software mirroring with another individual unit. You can create one LUN per individual disk unit. If you want to apportion the disk space, you can do so using partitions, file systems, or user directories.

A hot spare is a dedicated replacement disk on which users cannot store information. A hot spare is global: if any disk in a RAID 5

Group, RAID 3 Group, RAID 1 mirrored pair, or RAID 1/0 Group fails, the SP automatically rebuilds the failed disk’s structure on the hot spare. When the SP finishes rebuilding, the disk group functions as usual, using the hot spare instead of the failed disk. When you

RAID Types 2-9

2

RAID Types and Tradeoffs replace the failed disk, the SP copies the data from the former hot spare onto the replacement disk.

When the copy is done, the disk group consists of disks in the original slots, and the SP automatically frees the hot spare to serve as a hot spare again. A hot spare is most useful when you need the highest data availability. It eliminates the time and effort needed for someone to notice that a disk has failed, find a suitable replacement disk, and insert the disk.

When you plan to use a hot spare, make sure the disk has the capacity to serve in any RAID Group in the storage-system chassis. A RAID Group cannot use a hot spare that is smaller than a failed disk in the group.

You can have one or more hot spares per storage-system chassis. You can make any disk in the chassis a hot spare, except for a disk that serves for Core Software storage or the write cache vault. That is, a hot spare can be any of the following disks:

DPE or iDAE system without write caching:

DPE system with write caching: disks 3-119 disks 9-119 iDAE system with write caching:

30-slot SCSI-disk system: disks 5-29 disks A1-E1, A2-E2,

B3-E3, A4-E4

An example of hot spare usage for a deskside DPE storage system follows.



2

6

7

4

5

8

9

2

3

0

1

14

15

16

17

18

19

10

11

12

13

Hot spare

1. RAID 5 group consists of disk modules 0-4; RAID 1 mirrored pair is

modules 5 and 6; hot spare is module 9.

2. Disk module 3 fails.

3. RAID 5 group becomes modules 0, 1, 2, 9, and 4; now no hot spare is

available.

4. System operator replaces failed module 3 with a functional module.

5. RAID 5 group once again is 0-4 and hot spare is 9.

Figure 2-6 How a Hot Spare Works

RAID Types 2-11

2


RAID Benefits and Tradeoffs

This section reviews RAID types and explains their benefits and tradeoffs. You can create seven types of LUN:

• RAID 5 Group (individual access array)

• RAID 3 Group (parallel access array)

• RAID 1 mirrored pair

• RAID 1/0 Group (mirrored RAID 0 Group); a RAID 0 Group mirrored by the storage-system hardware

• RAID 0 Group (nonredundant individual access array); no inherent high-availability features, but can be software mirrored if the operating system supports mirroring

• Individual unit; no inherent high-availability features but can be software mirrored, if the operating system supports mirroring

• Hot spare; serves only as an automatic replacement for any disk in a RAID type other than 0; does not store data during normal system operations

Plan the disk unit configurations carefully. After a disk has been bound into a

LUN, you cannot change the RAID type of that LUN without unbinding it, and this means losing all data on it.

The following table compares the read and write performance, tolerance for disk failure, and relative cost per megabyte (Mbyte) of the RAID types. Figures shown are theoretical maximums.


Performance


2

Table 2-1 Performance, Availability, and Cost of RAID Types (Individual Unit = 1.0)

Disk configuration

RAID 5 Group with fivedisks

Relative read performance without cache

Relative write performance without cache

Relative cost per

Mbyte

Up to 5 with five disks

(for small I/O requests, 2 to 8 Kbytes)

Up to 1.25 with five disks

(for small I/O requests, 2 to

8 Kbytes)

1.25

RAID 3 Group with fivedisks

Up to 4 (for large I/O requests)

RAID 1 mirrored pair Up to 2

Up to 4 (for large I/O requests)

Up to 1

1.25

2

RAID 1/0 Group with

10 disks

Individual unit

Up to 10 Up to 5

1 1 1

Notes: These performance numbers are not based on storage-system caching. With caching, the performance numbers for RAID 5 writes improve significantly.

Performance multipliers vary with load on server and storage system.

RAID 5, with individual access, provides high read throughput for small requests (blocks of 2 to 8 Kbytes) by allowing simultaneous reads from each disk in the group. RAID 5 write throughput is limited by the need to perform four I/Os per request (I/Os to read and write data and parity information). However, write caching improves RAID 5 write performance.

RAID 3, with parallel access, provides high throughput for sequential, large block-size requests (blocks of more than 64 Kbytes).

With RAID 3, the system accesses all five disks in each request but need not read data and parity before writing – advantageous for large requests but not for small ones. RAID 3 employs SP memory without caching, which means you do not need the second SP and BBU that caching requires.

Generally, the performance of a RAID 3 Group increases as the size of the I/O request increases. Read performance increases rapidly with read requests up to 1Mbyte. Write performance increases greatly for sequential write requests that are greater than 256 Kbytes. For applications issuing very large I/O requests, a RAID 3 LUN provides significantly better write performance than a RAID 5 LUN.

RAID Benefits and Tradeoffs 2-13

2


Storage Flexibility

We do not recommend using RAID 3 in the same storage-system chassis with RAID 5 or RAID 1/0.

A RAID 1 mirrored pair has its disks locked in synchronization, but the SP can read data from the disk whose read/write heads are closer to it. Therefore, RAID 1 read performance can be twice that of an individual disk while write performance remains the same as that of an individual disk.

A RAID 0 Group (nonredundant individual access array) or RAID

1/0 Group (mirrored RAID 0 Group) can have as many I/O operations occurring simultaneously as there are disks in the group.

Since RAID 1/0 locks pairs of RAID 0 disks the same way as RAID 1 does, the performance of RAID 1/0 equals the number of disk pairs times the RAID 1 performance number. If you want high throughput for a specific LUN, use a RAID 1/0 or RAID 0 Group. A RAID 1/0

Group requires at least six disks; a RAID 0 Group, at least three disks.

An individual unit needs only one I/O operation per read or write operation.

RAID types 5, 1, 1/0, and 0 allow multiple LUNs per RAID Group. If you create multiple LUNs on a RAID Group, the LUNs share the

RAID Group disks, and the I/O demands of each LUN affect the I/O service time to the other LUNs. For best performance, you may want to use one LUN per RAID Group.

Certain RAID Group types — RAID 5, RAID 1, RAID 1/0, and RAID

0 — let you create up to 32 LUNs in each group. This adds flexibility, particularly with large disks, since it lets you apportion LUNs of various sizes to different servers, applications, and users. Conversely, with RAID 3, there can be only one LUN per RAID Group, and the group must include five or nine disks — a sizable block of storage to devote to one server, application, or user. However, the nature of

RAID 3 makes it ideal for that single-threaded type of application.

Data Availability and Disk Space Usage

If data availability is critical and you cannot afford to wait hours to replace a disk, rebind it, make it accessible to the operating system, and load its information from backup, then use a redundant RAID

Group: RAID 5, RAID 3, RAID 1 mirrored pair, or RAID 1/0. Or bind a RAID 0 Group or individual disk unit that you will later mirror with software mirroring. If data availability is not critical, or disk



2 space usage is critical, bind an individual unit or RAID 0 Group without software mirroring.

A RAID 1 mirrored pair or RAID 1/0 Group provides very high data availability. They are more expensive than RAID 5 or RAID 3 Groups, since only 50 percent of the total disk capacity is available for user

data, as shown on page 2-13.

A RAID 5 or RAID 3 Group provides high data availability, but requires more disks than a mirrored pair. In a RAID 5 or RAID 3

Group of five disks, 80 percent of the disk space is available for user data. So RAID 5 and RAID 3 Groups use disk space much more efficiently than a mirrored pair. A RAID 5 or RAID 3 Group is usually more suitable than a RAID 1 mirrored pair for applications where high data availability, good performance, and efficient disk space usage are all of relatively equal importance.

RAID Benefits and Tradeoffs 2-15

2


RAID 5 Group

1st disk user and parity data

2nd disk user and parity data

3rd disk user and parity data

4th disk user and parity data

5th disk user and parity data

RAID 3 Group

1st disk user data

2nd disk user data

3rd disk user data

4th disk user data

5th disk parity data

Disk Mirror (RAID 1 mirrored pair)

1st disk user data

2nd disk user data

50% user data

50% redundant data

100% user data

80% user data

20% parity data

RAID 0 Group

(nonredundant array)

1st disk user data

2nd disk user data

3rd disk user data

Hot Spare

Reserved

50% user data

50% redundant data

RAID 1/0 Group

1st disk user data

2nd disk user data

3rd disk user data

4th disk user data

5th disk user data

6th disk user data

Individual Disk Unit

User data 100% user data No user data

EMC1820

Figure 2-7 Disk Space Usage in the RAID Configurations

A RAID 0 Group (nonredundant individual access array) provides all its disk space for user files, but does not provide any high availability features.

A RAID 1/0 Group provides the best combination of performance and availability, at the highest cost per Mbyte of disk space.

An individual unit, like a RAID 0 Group, provides no high-availability features. All its disk space is available for user data, as shown in the figure above.



2

Guidelines for RAID Types

To decide when to use a RAID 5 Group, RAID 3 Group, mirror (that is, a RAID 1 mirrored pair or RAID 1/0 Group), a RAID 0 Group, individual disk unit, or hot spare, you need to weigh these factors:

• Importance of data availability

• Importance of performance

• Amount of data stored

• Cost of disk space

The following guidelines will help you decide on RAID types.

Use a RAID 5 Group (individual access array) for applications where

• Data availability is very important

• Large volumes of data will be stored

• Multitask applications use I/O transfers of different sizes

• Good read and moderate write performance are important (write caching can improve (RAID 5 write performance)

• You want the flexibility of multiple LUNs per RAID Group

Use a RAID 3 Group (parallel access array) for applications where


• Large volumes of data will be stored

• A single-task application uses large I/O transfers (more than 64

Kbytes). The operating system must allow transfers aligned to start at disk addresses that are multiples of 2 Kbytes from the start of the LUN.

Use a RAID 1 mirrored pair for applications where


• Speed of write access is important and write activity is heavy

Use a RAID 1/0 Group (mirrored nonredundant array) for applications where

• Data availability is critically important

• Overall performance is very important

Guidelines for RAID Types 2-17

2


Use a RAID 0 Group (nonredundant individual access array) for applications where

• High availability is not important

• Overall performance is very important

Use an individual unit for applications where

• High availability is not important

• Speed of write access is somewhat important

Use a hot spare where

• In any RAID 5, RAID 3, RAID 1/0 or RAID 1 Group, high availability is so important that you want to regain data redundancy quickly without human intervention if any disk in the Group fails

• Minimizing the degraded performance caused by disk failure in a

RAID 5 or RAID 3 Group is important



2

Sample Applications for RAID Types

This section describes some types of applications in which you would want to use a RAID 5 Group, RAID 3 Group, RAID 1 mirrored pair,

RAID 0 Group (nonredundant array), RAID 1/0 Group, or individual unit.

RAID 5 Group (individual access array) — Useful as a database repository or a database server that uses a normal or low percentage of write operations (writes are 33 percent or less of all I/O operations). Use a RAID 5 Group where multitask applications perform I/O transfers of different sizes. Write caching can significantly enhance the write performance of a RAID 5 Group.

For example, a RAID 5 Group is suitable for multitasking applications that require a large history database with a high read rate, such as a database of legal cases, medical records, or census information. A RAID 5 Group also works well with transaction processing applications, such as an airline reservations system, where users typically read the information about several available flights before making a reservation, which requires a write operation. You could also use a RAID 5 Group in a retail environment, such as a supermarket, to hold the price information accessed by the point-of-sale terminals. Even though the price information may be updated daily, requiring many write operations, it is read many more times during the day.

RAID 3 Group — A RAID 3 Group (parallel access array) works well with a single-task application that uses large I/O transfers (more than

64 Kbytes), aligned to start at a disk address that is a multiple of 2

Kbytes from the beginning of the logical disk. RAID 3 Groups can use

SP memory to great advantage without the second SP and battery backup unit required for storage-system caching.

You might use a RAID 3 Group for a single-task application that does large I/O transfers, like a weather tracking system, geologic charting application, medical imaging system, or video storage application.

RAID 1 mirrored pair — A RAID 1 mirrored pair is useful for logging or record-keeping applications because it requires fewer disks than a RAID 0 Group (nonredundant array) and provides high availability and fast write access. Or you could use it to store daily updates to a database that resides on a RAID 5 Group, and then, during off-peak hours, copy the updates to the database on the

RAID 5 Group.

Sample Applications for RAID Types 2-19

2


What Next?

RAID 0 Group (nonredundant individual access array) — Use a

RAID 0 Group where the best overall performance is important. In terms of high availability, a RAID 0 Group is less available than an individual unit. A RAID 0 Group (like a RAID 5 Group) requires a minimum of three disks. A RAID 0 Group serves well for an application that uses short-term data to which users need quick access.

RAID 1/0 Group (mirrored RAID 0 Group) — A RAID 1/0 Group provides the best balance of performance and availability. You can use it very effectively for any of the RAID 5 applications. A RAID 1/0

Group requires a minimum of four disks.

Individual unit — An individual unit is useful for print spooling, user file exchange areas, or other such applications, where high availability is not important or where the information stored is easily restorable from backup.

The performance of an individual unit is slightly less than a standard disk not in an storage system. The slight degradation results from SP overhead.

Hot spare — A hot spare provides no data storage but enhances the availability of each RAID 5, RAID 3, RAID 1, and RAID 1/0 Group in a storage system. Use a hot spare where you must regain high availability quickly without human intervention if any disk in such a

RAID Group fails. A hot spare also minimizes the period of degraded performance after a RAID 5 or RAID 3 disk fails.

This chapter explained RAID Group types and tradeoffs. To plan

LUNs and file systems for shared storage, continue to Chapter 3; or

for unshared storage, skip to Chapter 4. For details on storage-

system hardware — shared and unshared — skip to Chapter 5.

For storage-system management utilities, skip to Chapter 6.


3

Planning File Systems and LUNs with Shared

Switched Storage

This chapter shows a sample RAID, LUN, and Storage Group configuration with shared storage, and then provides worksheets for planning your own shared storage installation. Topics are

• Dual Paths to LUNs ...........................................................................3-2

• Sample Shared Switched Installation..............................................3-3

• Planning Applications, LUNs, and Storage Groups .....................3-6

Planning File Systems and LUNs with Shared Switched Storage 3-1

3

Planning File Systems and LUNs with Shared Switched Storage

Dual Paths to LUNs

A shared storage system includes two or more servers, one or two

Fibre Channel switches, and one or more storage systems, each with two SPs and Access Logix software.

With shared storage, there are two paths to each LUN in the storage system. The storage-system software, using optional software called

Application Transparent Failover (ATF), can automatically switch to the other path if a device (such as a host-bus adapter or cable) fails.

With unshared storage, if the server has two adapters and the storage system has two SPs, ATF software is available as an option. With two adapters and two SPs, ATF can perform the same function as with shared systems: automatically switch to the other path if a device

(such as host bus adapter or cable) fails.



3

Sample Shared Switched Installation

The following figure shows a sample shared switched

(high-availability) storage system connected to three servers: two servers in a cluster and one server running a database management program.


File Server (FS) Mail Server(MS)

Operating Operating system A system A

Database Server(DS)

Operating system B


Private storage

SP A

FS R5

Files A

SP B

FS R5

Files B

Disk IDs

4_0-4_9

MS R5

ISP A mail

MS R5

ISP B mail

3_0-3_9

Cluster

Storage Group

Database Server

Storage Group

MS R5

Users

DS R5

Users

MS R5

Specs

2_0-2_9

DS R5

Dbase2

1_0-1_9

DS R5 (6 disks) Dbase1

0_0-0_9

Path 1

Path 2

Figure 3-1 Sample Shared Switched High Availability installation

Sample Shared Switched Installation 3-3

3


The storage-system disk IDs and server Storage Group LUNs are as follows.

Clustered System LUNs

Database Server LUNs (DS) - SP A

File Server LUNs (FS) - SP B Mail Server LUNs (MS) - SP A

Disk IDs RAID type, storage type

4_0-4_4 RAID 5, Files A

4_5-4_9 RAID 5, Files B


2_0-2_4 RAID 5, ISP A mail

2_5-2_9 RAID 5, ISP B mail

3_0-3_4 RAID 5, Users

3_5-3_9 RAID 5, Specs


0_0, 0_ 1 RAID 1, Log file for database Dbase1

0_4-0_9 RAID 5 (6 disks), Dbase1

1_0-1_4 RAID 5, Users

1_5-1_9 RAID 5, Dbase2

6_0, 6_1 – Hot spare (automatically replaces a failed disk in any server’s LUN)

With 36-Megabyte disks, the LUN storage capacities and drive names are as follows.

File Server — 288 Gbytes on two LUN s

FS R5

FilesA

Unit U on five disks bound as a RAID 5 Group for

144 Gbytes of storage; for file storage.

FS R5

FilesB

Unit V on five disks bound as a RAID 5 Group for

144 Gbytes of storage; for file storage.



3

Mail Server — 576 Gbytes on four LUNs

MS R5

ISP mail

Unit O on five disks bound as a RAID 5 Group for

144 Gbytes of storage; for the mail delivered via ISP A.

MS R5

ISP mail

Unit P on five disks bound as a RAID 5 Group for

144 Gbytes of storage; for the mail delivered via ISP B.

MSR5

Users

Unit Q on five disks bound as a RAID 5 Group for

144 Gbytes of storage; for user directories and files.

MS R5

Specs

Unit R on five disks bound as a RAID 5 Group for

144 Gbytes of storage; for specifications.

Database Server — 416 Gbytes on four LUNs

DS R5

Users

Unit users on five disks bound as a RAID 5 Group for

144 Gbytes of storage; for user directories.

DS R5

Dbase2 Unit dbase2 on five disks bound as a RAID 5 Group for 144 Gbytes of storage; for the second database system.

DS R1

Logs

Unit logfiles on two disks bound as a RAID 1 mirrored pair for 36 Gbytes of storage; for the database log files.

DS R5

Dbase1

Unit dbase on six disks bound as a RAID 5 Group for

180 Gbytes of storage; for the primary database system.

Sample Shared Switched Installation 3-5

3


Planning Applications, LUNs, and Storage Groups

This section helps you plan your shared storage use — the applications to run, the LUNs that will hold them, and the Storage

Groups that will belong to each server. The worksheets to help you do this include

• Application and LUN planning worksheet - lets you outline your storage needs.

• LUN and Storage Group planning worksheet - lets you decide on the disks to compose the LUNs and the LUNs to compose the

Storage Groups for each server.

• LUN details worksheet - lets you plan each LUN in detail.

Make as many copies of each blank worksheet as you need. You will need this information later when you configure the shared storage system.

Sample worksheets appear later in this chapter.

Application and LUN Planning

Use the following worksheet to list the applications you will run and the RAID type and size of LUN to hold them. For each application that will run in the SAN, write the application name, file system (if any), RAID type, LUN ID (ascending integers, starting with 0), disk space required, and finally the name of the servers and operating systems that will use the LUN.



3

Application and LUN Planning Worksheet

Application

File system, partition, or drive

RAID type of

LUN

LUN

ID (hex)

Disk space required

(Gbytes)

Server name and operating system

Application

Mail 1

Mail 2

Database index

A sample worksheet begins as follows:

File system, partition, or drive

RAID type of

LUN

RAID 5

RAID 5

LUN

ID (hex)

0

1

RAID 1 2


(Gbytes)

72 Gb

72 Gb

18 Gb


Server1, NT

Server1, NT

Server2, NT

Completing the Application and LUN Planning Worksheet

Application . Enter the application name or type.

File system, partition , or drive. Write the drive letter (for Windows only) and the partition, file system, logical volume, or drive letter name, if any.

With a Windows operating system, the LUNs are identified by drive letter only. The letter does not help you identify the disk configuration (such as RAID 5). We suggest that later, when you use the operating system to create a partition on a LUN, you use the disk administrator software to assign a volume label that describes the

RAID configuration. For example, for drive T, assign the volume ID

RAID5_T . The volume label will then identify the drive letter.

Planning Applications, LUNs, and Storage Groups 3-7

3


RAID type of LUN . This is the RAID Group type you want for this partition, file system, or logical volume. The features of RAID types

are explained in Chapter 2. For a RAID 5, RAID 1, RAID 1/0, and

RAID 0 Group, you can create one or more LUNs on the RAID

Group. For other RAID types, you can create only one LUN per RAID

Group.

LUN ID. The LUN ID is a hexadecimal number assigned when you bind the disks into a LUN. By default, the ID of the first LUN bound is 0, the second 1, and so on. Each LUN ID must be unique within the storage system, regardless of its Storage Group or RAID Group.

The maximum number of LUNs supported on one host-bus adapter depends on the operating system.

Disk space required (Gbytes) . Consider the largest amount of disk space this application will need, then add a factor for growth.

Server hostname and operating system . Enter the server hostname

(or, if you don’t know the name, a short description that identifies the server) and the operating system name, if you know it.

LUN and Storage Group Planning Worksheet

Use the following worksheet to select the disks that will make up the

LUNs and Storage Groups in the SAN. A shared storage system can include up to 100 disks, numbered 0 through 99, left to right from the bottom up.



3

LUN and Storage Group Planning Worksheet

11_0 11_1 11_211_3 11_4 11_5 11_6 11_7 11_811_9

10_0 10_1 10_210_3 10_4 10_5 10_6 10_7 10_8 10_9

9_0 9_1 9_2 9_3 9_4 9_5 9_6 9_7 9_8 9_9

8_0 8_1 8_2 8_3 8_4 8_5 8_6 8_7 8_8 9_9

7_0 7_1 7_2 7_3 7_4 7_5 7_6 7_7 7_8 7_9

6_0 6_1 6_2 6_3 6_4 6_5 6_6 6_7 6_8 6_9

5_0 5_1 5_2 5_3 5_4 5_5 5_6 5_7 5_8 5_9

4_0 4_1 4_2 4_3 4_4 4_5 4_6 4_7 4_8 4_9

3_0 3_1 3_2 3_3 3_4 3_5 3_6 3_7 3_8 3_9

2_0 2_1 2_2 2_3 2_4 2_5 2_6 2_7 2_8 2_9

1_0 1_1 1_2 1_3 1_4 1_5 1_6 1_7 1_8 1_9

0_0 0_1 0_2 0_3 0_4 0_5 0_6 0_7 0_8 0_9

Storage system number or name:_______________

Storage Group ID or name:______ Server hostname:_____________________ Dedicated Shared

LUN ID or name_______RAID type ___ Cap. (Gb) _____ Disk IDs_________________________________________















3


Part of a sample LUN and Storage Group worksheet follows.

3_0 3_1 3_2 3_3 3_4 3_5 3_6 3_7 3_8 3_9

2_0 2_1 2_2 2_3 2_4 2_5 2_6 2_7 2_8 2_9

LUN 2

RAID 1

1_0 1_1 1_2 1_3 1_4 1_5 1_6 1_7 1_8 1_9

LUN 0

RAID 5

0_0 0_1 0_2 0_3 0_4 0_5 0_6 0_7 0_8 0_9 LUN 1

RAID 5

SS1

Mail 1 Server1

X

0

5 72 0_0, 0_1, 0_2, 0_3, 0_4

5

72 0_5, 0_6, 0_7, 0_8, 0_9

LUN ID or name_______RAID type ___ Cap. (Gb) _____ Disk IDs______________________________


Index1

1

18

1_0, 1_1




Completing the LUN and Storage Group Planning Worksheet

As shown, draw circles around the disks that will compose each

LUN, and within each circle specify the RAID type (for example,

RAID 5) and LUN ID. This is information you will use to bind the disks into LUNs. For disk IDs, use the form shown. This form is

enclosure_diskID, where enclosure is the enclosure number (the bottom one is 0, above it 1, and so on) and diskID is the disk position (left is 0, next is 1, and so on).

None of the disks 0_0 through 0_8 may be used as a hot spare.

Next, complete as many of the Storage System sections as needed for all the Storage Groups in the SAN. Copy the (blank) worksheet as needed for all Storage Groups in each storage system.

A storage system is any group of enclosures connected to a DPE; it can include up to 11 DAE enclosures for a total of 120 disks. If a



3

Storage Group will be dedicated (not accessible by another system in a cluster), mark the Dedicated box at the end of its line; if the Storage

Group will be accessible to one or more other servers in a cluster, write the hostnames of all servers and mark the Shared box.

LUN Details Worksheet

Use the following LUN details worksheet to plan the individual

LUNs. Complete as many of these as needed for all LUNs in your

SAN.


3



Storage system (complete this section once for each storage system)

Storage-system number or name:______

Storage-system installation type

❏ Unshared Direct ❏ Shared-or-Clustered Direct ❏ Shared Switched

SP FC-AL address ID (unshared only): SP A:_____SP B:_____

SP memory (Mbytes):

❏ Use for caching

❏ Use for RAID 3

SP A:___ SP B:____

Read cache size:__ MB Write cache size: __ MB Cache page size:___KB

RAID Group ID: Size,GB:

LUN ID:_____

LUN size,GB: Disk IDs:

RAID type: ❏ RAID 5

❏ RAID 1/0

❏

❏

RAID 3 - Memory, MB:___

Individual disk

Caching: ❏ Read and write ❏ Write ❏ Read ❏ None

❏ A ❏ B

❏ RAID 1 mirrored pair ❏ RAID 0

❏ Hot spare

SP:

Servers that can access this LUN:

Operating system information: Device name: File system, partition, or drive:

LUN ID:____

RAID Group ID: Size,GB: LUN size,GB: Disk IDs:


❏ RAID 1/0

❏

❏


Individual disk



Operating system information: Device name:

❏ A ❏ B


❏ Hot spare

SP:

File system, partition, or drive:


LUN ID:____



❏ RAID 1/0

❏

❏


Individual disk




❏ A ❏ B


❏ Hot spare

SP:




3



Storage-system number or name:__ SS1 ____


❏ Unshared Direct ❏ Shared-or-Clustered Direct

X

Shared Switched


SP memory (Mbytes): SP A:_ 256 __ SP B:_ 256 __

❏ Use for caching

❏ Use for RAID 3

Read cache size:_ 80 _ MB Write cache size: _ 160 _ MB Cache page size:_ 2 __KB

LUN ID:__ 0 ___

RAID Group ID: 0 Size,GB: 72 LUN size,GB: 72 Disk IDs:

RAID type:

X

RAID 5

❏ RAID 1/0

❏ RAID 3 - Memory, MB:___

❏ Individual disk

Caching:

X

Read and write ❏ Write ❏ Read ❏ None

Servers that can access this LUN: Server1

0_0,0_1,0_2,0_3,0_4 SP:

X

A ❏ B


❏ Hot spare

Operating system information: Device name: File system, partition, or drive: T

RAID Group ID:

LUN ID:__ 1 __

0_5, 0_6, 0_7, 0_8, 0_9

1 Size,GB: 72 LUN size,GB: 72 Disk IDs: SP:

X

A ❏ B

RAID type:

X

RAID 5

❏ RAID 1/0


❏ Individual disk


❏ Hot spare

Caching: X Read and write ❏ Write ❏ Read ❏ None


Operating system information: Device name: File system, partition, or drive: U

LUN ID:__ 2 __

RAID Group ID: 2 Size,GB:

RAID type:

X

❏

RAID 5

RAID 1/0

LUN size,GB: 18 Disk IDs:


❏ Individual disk




1_0, 1_1


SP: ❏ A

X

B

X

RAID 1 mirrored pair ❏ RAID 0

❏ Hot spare

V


3


Completing the LUN Details Worksheet

Complete the header portion of the worksheet for each storage system as described below. Copy the blank worksheet as needed.

Storage-system entries

Storage-system installation type , specify Shared Switched storage.

SP FC-AL address ID . This does not apply to shared storage, in which the switch determines the address of each device.

Use memory for caching. You can use SP memory for read/write caching or RAID 3. (Using both caching and RAID 3 in the same storage system is not recommended.) You can use different cache settings for different times of day (for example, for user I/O during the day, use more write cache; for sequential batch jobs at night, use more read cache. You enable caching for specific LUNs

— allowing you to tailor your cache resources according to priority. If you choose caching, check the box and continue to the next step; for RAID 3, skip to the RAID Group ID entry.

Read cache size.

If you want a read cache, it should generally be about one third of the total available cache memory.

Write cache size.

The write cache should be two thirds of the total available. Some memory is required for system overhead, so you cannot determine a precise figure at this time. For example, for

256 Mbytes of total memory, you might have 240 Mbytes available, and you would specify 80 Mbytes for the read cache and 160 Mbytes for the write cache.

Cache page size. This applies to both read and write caches. It can be 2, 4, 8, or 16 Kbytes. As a general guideline, we suggest

• For a general-purpose file server — 8 Kbytes

• For a database application — 2 or 4 Kbytes

The ideal cache page size depends on the operating system and application.

Use memory for RAID 3 . If you want to use the SP memory for

RAID 3, check the box.

RAID Group/LUN Entries

Complete a RAID Group/LUN entry for each LUN and hot spare.



3

LUN ID . The LUN ID is a hexadecimal number assigned when you bind the disks into a LUN. By default, the ID of the first LUN bound is 0, the second 1, and so on. Each LUN ID must be unique within the storage system, regardless of its Storage Group or

RAID Group.

The maximum number of LUNs supported on one host-bus adapter depends on the operating system.

RAID Group ID . This ID is a hexadecimal number assigned when you create the RAID Group. By default, the number of the first RAID Group in a storage system is 0, the second 1, and so on, up to the maximum of 1F (31).

Size (RAID Group size). Enter the user-available capacity in gigabytes (Gbytes) of the whole RAID Group. You can determine the capacity as follows:

RAID5 or RAID-3 Group: disk-size * (number-of-disks - 1)

RAID 1/0 or RAID-1 Group: (disk-size * number-of-disks) / 2

RAID 0 Group:

Individual unit: disk-size * number-of-disks disk-size

For example,

• A five-disk RAID 5 or RAID 3 Group of 36-Gbyte disks holds

144 Gbytes;

• An eight-disk RAID 1/0 Group of 36-Gbyte disks also holds

144 Gbytes;

• A RAID 1 mirrored pair of 36-Gbyte disks holds 36 Gbytes; and

• An individual disk of an 36-Gbyte disk also holds 36 Gbytes.

Each disk in the RAID Group must have the same capacity; otherwise, you will waste disk storage space.

LUN size . Enter the user-available capacity in gigabytes (Gbytes) of the LUN. You can make this the same size as the RAID Group, above. Or, for a RAID 5, RAID 1, RAID 1/0, or RAID 0 Group, you can make the LUN smaller than the RAID Group. You might do this if you wanted a RAID 5 Group with a large capacity and wanted to place many smaller capacity LUNs on it; for example, to specify a LUN for each user. However, having multiple LUNs


3


Table 3-1 per RAID Group may adversely impact performance. If you want multiple LUNs per RAID Group, then use a RAID Group/LUN series of entries for each LUN.

Disk IDs . Enter the ID(s) of all disks that will make up the LUN or hot spare. These are the same disk IDs you specified on the previous worksheet. For example, for a RAID 5 Group in the DPE

(enclosure 0, disks 2 through 6), enter 0_2, 0_3, 0_4, 0_5, and 0_6.

SP . Specify the SP that will own the LUN: SP A or SP B. You can let the management program automatically select the SP to balance the workload between SPs; to do so, leave this entry blank.

RAID type . Copy the RAID type from the previous worksheet.

For example, RAID 5 or hot spare. For a hot spare (not strictly speaking a LUN at all), skip the rest of this LUN entry and continue to the next LUN entry (if any).

If this is a RAID 3 Group, specify the amount of SP memory for that group. To work efficiently, each RAID 3 Group needs at least

6 Mbytes of memory.

Caching

. If you want to use caching (entry on page 3-14), you can

specify whether you want caching — read and write, read, or write for this LUN. Generally, write caching improves performance far more than read caching. The ability to specify caching on a LUN basis provides additional flexibility, since you can use caching for only the units that will benefit from it. Read and write caching recommendations follow.

Cache Recommendations for Different RAID Types

RAID 5 RAID 3

Highly Recommended Not allowed

RAID 1 RAID 1/0 RAID 0 Individual Unit

Recommended Recommended Recommended Recommended

Servers that can access this LUN . Enter the name of each server

(copied from the LUN and Storage Group worksheet).

Operating system information: Device name. Enter the operating system device name, if this is important and if you know it. Depending on your operating system, you may not be able to complete this field now.



3

What Next?

File system, partition, or drive . Write the name of the file system, partition, or drive letter you will create on this LUN. This is the same name you wrote on the application worksheet.

On the following line, write any pertinent notes; for example, the file system mount- or graft-point directory pathname (from the root directory). If this storage system’s chassis will be shared with another server, and the other server is the primary owner of this disk, write secondary. (As mentioned earlier, if the storage system will be used by two servers, we suggest you complete one of these worksheets for each server.)

This chapter outlined the planning tasks for shared storage systems.

If you have completed the worksheets to your satisfaction, you are ready to learn about the hardware needed for these systems as

explained in Chapter 5.


3



Invisible Body Tag

4

Planning LUNs and File

Systems with Unshared

Direct Storage

This chapter shows sample RAID and LUN configurations with direct storage installations and then provides worksheets for planning your own storage installation. Topics are

• Dual SPs and Paths to LUNs ............................................................4-2

• Unshared Direct and Shared-or-Clustered Direct Storage...........4-2

• Planning Applications and LUNs ...................................................4-4

Planning LUNs and File Systems with Unshared Direct Storage 4-1

4

Planning LUNs and File Systems with Unshared Direct Storage

Dual SPs and Paths to LUNs

If a storage system has two SPs, there are two routes to its LUNs. If the server has two adapters and the storage system has two SPs,

Application Transparent Failover (ATF). ATF can automatically switch to the other path, without disrupting applications, if a device

(such as a host-bus adapter, cable, or SP) fails.

Unshared Direct and Shared-or-Clustered Direct Storage

This section explains the direct (unswitched) options available for connecting storage systems to servers. As needs change, you may want to change a configuration. You can do so without changing your

LUN configuration or losing user data.

There are two types of installation:

• Unshared direct with one server is the simplest and least costly;

• Shared-or-clustered direct lets two clustered servers share storage resources with high availability.

Sample Unshared Direct Installation

Server

Disk IDs

100-109

010-019

SP A

Database

RAID 5

Sys

RAID 1

SP B

Users

RAID 5

Clients, mail

RAID 5

Figure 4-1 Unshared Direct Installation

Path 1

Path 2

EMC1825

4-2



4

The storage system disk IDs and LUNs are as follows. The LUN capacities shown assume 36-Gbyte disks.

LUNs - SP A and SP B, 422 Gbytes

Disk IDs RAID type, storage type, capacity

0_0, 0_1 RAID 1, System disk, 36 Gbytes

0_2-0_9 RAID 5 (8 disks), Clients and Mail, 216 Gbytes

1_0-1_4 RAID 5, Database, 144 Gbytes

1_5 Disk, Temporary storage, 36 Gbytes

Sample Shared-or-Clustered Direct Installation

Server 1 (S1) Server 2 (S2)

Storage system

SP A

S2 Customers

RAID 5

SP B

S1Dbase

RAID 5

Path 1

Path 2

Figure 4-2 Sample Clustered Installation

If each disk holds 36 Gbytes, then the storage-system chassis provides

Server 1 with 256 Gbytes of disk storage, 220 Gbytes highly available; it provides Server 2 with 216 Gbytes of storage, all highly available.

Each server has its own SP, which controls that server’s LUNs; those

LUNs remain primary to that server. The LUNs are as follows.

Server1 LUNs (S1) - SP A, 256 Gbytes


0_0, 0_1 RAID 1, System disk, 36 Gbytes

0_2 Disk, Temporary storage, 36 Gbytes

0_3-0_7 RAID 5, Database, 144 Gbytes

0_8-0_ 9 RAID 1, Users, 36 Gbytes

Server2 LUNs (S2) - SP B, 216 Gbytes


1_0-1_7 RAID 5 (8 disks), Cust Accounts, 216

Gbytes

Unshared Direct and Shared-or-Clustered Direct Storage 4-3

4


Planning Applications and LUNs

This section helps you plan your unshared (direct) storage use — applications you want to run and the LUNs that will hold them. The worksheets to help you do this include

• Application and file system planning worksheet - lets you outline your storage needs.

• LUN planning worksheet - lets you decide on the disks that will compose the LUNs.

• LUN details worksheet - lets you plan each LUN in detail.

Make as many copies of each blank worksheet as you need. You will need this information later when you configure the shared storage system.

Sample file system, Storage Group, and LUN worksheets appear later in this chapter.

Application and LUN Planning

Use the following worksheet to plan your file systems and RAID types. For each application, write the application name, file system (if any), RAID type, LUN ID (ascending integers, starting with 0), disk space required, and finally the name of the servers and operating systems that will use the LUN.

4-4



4

Application and LUN Planning Worksheet

Application File system (if any)

RAID type of

LUN

LUN

ID (hex)


(Gbytes)


Application

Mail 1

Mail 2

Database index

A sample worksheet begins as follows:

File system (if any)

RAID type of

LUN

RAI D 5

RAI D 5

RAI D 1 2

0

1

LUN

ID (hex)


(Gbytes)

72 Gb

72 Gb

18 Gb


Server1, NT

Server1, NT

Server2, NT

Completing the Application and LUN Planning Worksheet

Application . Enter the application name or type.

File system, partition , or drive. Write the drive letter (for Windows only) and the partition, file system, logical volume, or drive letter

(Windows only) name.

With a system such as Windows NT, the LUNs are identified by drive letter only. The letter does not help you identify the disk configuration (such as RAID 5). We suggest that later, when you use the operating system to create a partition on the unit, you use the disk administrator software to assign a volume label that describes the

Planning Applications and LUNs 4-5

4


RAID configuration. For example, for drive T, assign the volume ID

RAID5_T . The volume label will then identify the drive letter.

RAID type of LUN is the RAID Group type you want for this partition, file system, or logical volume. The features of RAID types

are explained in Chapter 2. For a RAID 5, RAID 1, RAID 1/0, and

RAID 0 Group, you can create one or more LUNs on the RAID

Group. For other RAID types, you can create only one LUN per RAID

Group.

LUN ID is a hexadecimal number assigned when you bind the disks into a LUN. By default, the ID of the first LUN bound is 0, the second

1, and so on. Each LUN ID must be unique within the storage system, regardless of its Storage Group or RAID Group.

The maximum number of LUNs supported on one host-bus adapter depends on the operating system. Some systems allow only eight

LUNs (numbers 0 through 7). For an operating system with this restriction, if you want a hot spare, assign the hot spare an ID above

7; for example, 8 or 9. The operating system never accesses a hot spare, so the ID is irrelevant to it.

Disk space required (Gbytes) , Consider the largest amount of disk space this application will need, then add a factor for growth.

Server hostname and operating system Enter the server hostname

(or, if you don’t know the name, a short description that identifies the server) and the operating system name, if you know it.

If this storage system will be used by two servers, provide a copy of this worksheet to the other server. This is particularly important where one server may take over the other’s LUNs. If a LUN will be shared, on the Notes section of the LUN details worksheet, write

Primary to server-name or Secondary to server-name.

LUN Planning Worksheet

Use one of the following worksheets (Rackmount or Deskside) to select the disks that will make up the LUNs. Depending on model, a full-fibre rackmount storage system can include up to 100 disks, numbered 0 through 99, left to right from the bottom up.

Again depending on model, a deskside storage system can hold ten,

20, or 30 disks.

4-6



4

LUN Planning Worksheet - Rackmount

Full-fibre storage system

11_0 11_1 11_2 11_3 11_4 11_5 11_6 11_7 11_8 11_9

10_0 10_1 10_2 10_3 10_4 10_5 10_6 10_7 10_8 10_9

9_0 9_1 9_2 9_3 9_4 9_5 9_6 9_7 9_8 9_9

8_0 8_1 8_2 8_3 8_4 8_5 8_6 8_7 8_8 8_9

7_0 7_1 7_2 7_3 7_4 7_5 7_6 7_7 7_8 7_9

6_0 6_1 6_2 6_3 6_4 6_5 6_6 6_7 6_8 6_9

5_0 5_1 5_2 5_3 5_4 5_5 5_6 5_7 5_8 5_9

4_0 4_1 4_2 4_3 4_4 4_5 4_6 4_7 4_8 4_9

3_0 3_1 3_2 3_3 3_4 3_5 3_6 3_7 3_8 3_9

2_0 2_1 2_2 2_3 2_4 2_5 2_6 2_7 2_8 2_9

1_0 1_1 1_2 1_3 1_4 1_5 1_6 1_7 1_8 1_9

0_0 0_1 0_2 0_3 0_4 0_5 0_6 0_7 0_8 0_9

LUN number_______RAID type ___ Cap. (Gb) _____ Disk IDs_________________________________________









4


LUN Planning Worksheet - Deskside

Full-fibre storage system

0_0

0_1

0_2

0_3

0_4

0_5

0_6

0_7

0_8

0_9

1_0

1_1

1_2

1_3

1_4

1_5

1_6

1_7

1_8

1_9

2_4

2_5

2_6

2_7

2_8

2_9

2_0

2_1

2_2

2_3

Storage system number_____

LUN number_______RAID type ___ Cap. (Gb) _____ Disk IDs________________________________________








4-8



4

A sample LUN worksheet follows.

2_0 2_1 2_2 2_3 2_4 2_5 2_6 2_7 2_8 2_9

LUN 2

RAID 1

1_0 1_1 1_2 1_3 1_4 1_5 1_6 1_7 1_8 1_9

LUN 0

RAID 5

0_0 0_1 0_2 0_3 0_4 0_5 0_6 0_7 0_8 0_9

LUN 1

RAID 5

0

5

144

0_0, 0_1, 0_2, 0_3, 0_4


2

5

36 1_0, 1_1





Completing the LUN Planning Worksheet

As shown, draw circles around the disks that will compose each

LUN, and within each circle specify the RAID type (for example,

RAID 5) and LUN ID. This is information you will use to bind the disks into LUNs. For disk IDs, use the form shown. This form is

enclosure_diskID, where enclosure is the enclosure number (the bottom one is 0, above it 1, and so on) and diskID is the disk position (left is 0, next is 1, and so on).

None of the disks 0_0 through 0_8 may be used as a hot spare.


Next, complete as many of the LUN sections as needed for each storage system.Copy the (blank) worksheet as needed for all LUNs in each storage system. A storage system is any group of enclosures connected to a DPE; a full-fibre system can include up to nine DAE enclosures for a total of 100 disks.

Use the following LUN details worksheet to plan the individual

LUNs. Complete as many of these as needed for all LUNs.


4




Storage-system number or name:______



SP FC-AL address ID (unshared only):

SP memory (Mbytes):

V Use for caching

V Use for RAID 3

SP A:______

SP A:_____SP B:_____

SP B:______

Read cache size:___ MB Write cache size: ___ MB Cache page size:___KB

LUN ID:_____


RAID type: V RAID 5

V RAID 1/0

V

V



Individual disk

Caching: V Read and write V Write V Read V None

SP: V A V B

V RAID 1 mirrored pair V RAID 0

V Hot spare



LUN ID:_____

RAID Group ID: Size,GB: LUN size,GB: Disk IDs:

RAID type: V RAID 5

V RAID 1/0

V

V


Individual disk




V A V B


V Hot spare

SP:



LUN ID:_____


RAID type: V RAID 5

V RAID 1/0

V

V


Individual disk




V A V B


V Hot spare

SP:


4-10



4



Storage-system number or name:__ 1 ____




SP memory (Mbytes):

V X Use for caching

V Use for RAID 3

SP A:_ 128 __ SP B:_ 128 __

Read cache size:_ 40 _ MB Write cache size: _ 80 _ MBCache page size:_ 2 __KB

LUN ID:__ 0 ___

RAID Group ID: 0 Size,GB: 144 LUN size,GB: 144

0_0, 0_1, 0_2, 0_3, 0_4

RAID type: V RAID 5

V

RAID 1/0

V RAID 3 - Memory, MB:___

V

Individual disk

Caching:

X

Read and write V Write V Read V None

SP: X A V B


V

Hot spare



T

LUN ID:__ 1 __

RAID Group ID: 1 Size,GB: 144 LUN size,GB: 144 Disk IDs:

0_5, 0_6, 0_7, 0_8, 0_9

SP: V A V B

RAID type:

X

RAID 5

V RAID 1/0


V Individual disk

Caching:

V

Read and write

V

Write

V

Read

V

None


V Hot spare

Servers that can access this LUN: Server1

Operating system information: Device name: File system, partition, or drive: U

RAID Group ID: 2 Size,GB:

18

LUN ID:__ 2 __

LUN size,GB: 36 Disk IDs:

RAID type: V RAID 5

V RAID 1/0


V Individual disk




1_0, 1_1


SP: X A V B

X V RAID 1 mirrored pair V RAID 0

V Hot spare

V


4


Completing the LUN Details Worksheet

Complete the header portion of the worksheet for each storage system as described below. Copy the blank worksheet as needed.

Sample completed LUN worksheets appear later.

Storage-System Entries

Storage-system configuration . Specify Unshared Direct (one server) or Shared-or-Clustered Direct (two servers).

For any multiple-server configuration, each server will need cluster software.

SP FC-AL address ID . For unshared storage, which uses FC-AL addressing, each SP (and each other node) on a Fibre Channel loop must have a unique FC-AL address ID. You set the SP FC-AL address

ID using switches on the back panel of the SP. The valid FC-AL address ID range is a number 0 through 125 decimal, which is 0 through 7D hexadecimal. For any number above 9, we suggest hexadecimal, since the switches are marked in hexadecimal.

If you have two FC-AL loops, we suggest a unique FC-AL address ID for each SP on both loops.

SP memory . Enter the amount of memory each SP has. If a storage system has two SPs, they will generally have the same amount of memory. You can allocate this memory to storage-system caching or

RAID 3 use.

Use memory for caching . You can use SP memory for read/write caching or RAID 3. (Using both caching and RAID 3 in the same storage system not recommended.) You can use different cache settings for different times of day (for example, for user I/O during the day, use more write cache; for sequential batch jobs at night, use more read cache. You enable caching for specific LUNs — allowing you to tailor your cache resources according to priority. If you choose caching, check the box and continue to the next step; for RAID 3, skip to the RAID Group ID entry.

Read cache size . If you want a read cache, it should generally be about one third of the total available cache memory.

Write cache size . The write cache should be two thirds of the total available. Some memory is required for system overhead, so you cannot determine a precise figure at this time. For example, for 256

Mbytes of total memory, you might have 240 Mbytes available, and

4-12



4 you would specify 80 Mbytes for the read cache and 160 Mbytes for the write cache.

Cache page size . This applies to both read and write caches. It can be

2, 4, 8, or 16 Kbytes. As a general guideline, we suggest

For a general-purpose file server — 8 Kbytes

For a database application — 2 or 4 Kbytes

The ideal cache page size depends on the operating system and application.

Use memory for RAID 3 . If you want to use the SP memory for

RAID 3, check the box.

RAID Group/LUN Entries

Complete a RAID Group/LUN entry for each LUN and hot spare.

LUN ID . The LUN ID is a hexadecimal number assigned when you bind the disks into a LUN. By default, the ID of the first LUN bound is 0, the second 1, and so on. Each LUN ID must be unique within the storage system, regardless of its Storage Group or RAID Group.

The maximum number of LUNs supported on one host-bus adapter depends on the operating system. Some systems allow only eight

LUNs (numbers 0 through 7). For an operating system with this restriction, if you want a hot spare, assign the hot spare an ID above

7; for example, 8 or 9. The operating system never accesses a hot spare, so the ID is irrelevant to it.

RAID Group ID . This is a hexadecimal number assigned when you create the RAID Group. By default, the number of the first RAID

Group in a storage system is 0, the second 1, and so on, up to the maximum of 1F (31).

Size (RAID Group size) Enter the user-available capacity in gigabytes

(Gbytes) of the whole RAID Group. You can determine the capacity as follows:

RAID-5 or RAID-3 Group: disk-size * (number-of-disks - 1)

RAID 1/0 or RAID-1

Group:

(disk-size * number-of-disks) / 2

RAID-0 Group:

Individual unit: disk-size * number-of-disks disk-size


4


For example,

• A five-disk RAID 5 or RAID 3 Group of 36-Gbyte disks holds

144 Gbytes;

• An eight-disk RAID 1/0 Group of 36-Gbyte disks also holds

144Gbytes;

• A RAID 1 mirrored pair of 36-Gbyte disks holds 36 Gbytes; and

• An individual disk of a 36-Gbyte disk also holds 36 Gbytes.

Each disk in the RAID Group must have the same capacity; otherwise, you will waste disk storage space.

LUN Size . Enter the user-available capacity in gigabytes (Gbytes) of the LUN. You can make this the same size as the RAID Group, above.

Or, for a RAID 5, RAID 1, RAID 1/0, or RAID 0 Group, you can make the LUN smaller than the RAID Group. You might do this if you wanted a RAID 5 Group with a large capacity and wanted to place many smaller capacity LUNs on it; for example, to specify a LUN for each user. However, having multiple LUNs per RAID Group may adversely impact performance. If you want multiple LUNs per RAID

Group, then use a RAID Group/LUN series of entries for each LUN.

Disk IDs . Enter the ID(s) of all disks that will make up the LUN or hot spare. These are the same disk IDs you specified on the previous worksheet. For example, for a RAID-5 Group in the DPE (enclosure 0, disks 2 through 6), enter 0_2, 0_3, 0_4, 0_5, and 0_6.

SP . Specify the SP that will own the LUN: SP A or SP B. You can let the management program automatically select the SP to balance the workload between SPs; to do so, leave this entry blank.

RAID type . Copy the RAID type from the previous worksheet. For example, RAID 5 or hot spare. For a hot spare (not strictly speaking a

LUN at all), skip the rest of this LUN entry and continue to the next

LUN entry (if any).

If this is a RAID 3 Group, specify the amount of SP memory for that group. To work efficiently, each RAID 3 Group needs at least

6 Mbytes of memory.

Caching.

If you want to use caching (entry on page 4-12), you can

specify whether you want caching — read and write, read, or write for this LUN. Generally, write caching improves performance far more than read caching. The ability to specify caching on a LUN basis provides additional flexibility, since you can use caching for only the

4-14



4

Table 4-1 units that will benefit from it. Read and write caching recommendations follow.

Cache Recommendations for Different RAID Types

RAID 5 RAID 3

Highly Recommended Not allowed

What Next?

RAID 1 RAID 1/0 RAID 0 Individual Unit

Recommended Recommended Recommended Recommended

Servers that can access this LUN . Enter the name of each server that will be able to use the LUN. Normally, you need to restrict access by establishing SP ownership of LUNs when you bind them.

Operating system information: Device name. Enter the operating system device name, if this is important and if you know it.

Depending on your operating system, you may not be able to complete this field now.

File system, partition, or drive . Write the name of the file system, partition, or drive letter you will create on this LUN. This is the same name you wrote on the application worksheet.

On the following line, write any pertinent notes; for example, the file system mount- or graft-point directory pathname (from the root directory). If this storage system’s chassis will be shared with another server, and the other server is the primary owner of this disk, write secondary . (If the storage system will be used by two servers, we suggest you complete one of these worksheets for each server.)

This chapter outlined the planning tasks for unshared storage systems. If you have completed the worksheets to your satisfaction, you are ready to learn about the hardware needed for these systems

as explained in Chapter 5.


4


4-16


Invisible Body Tag

5

Storage System

Hardware

This chapter describes the storage-system hardware components.

Topics are

• Hardware for Shared Storage...........................................................5-3

• Hardware for Unshared Storage......................................................5-6

• Planning Your Hardware Components ........................................ 5-11

• Hardware Data Sheets.....................................................................5-14

• Cabinets for Rackmount Enclosures .............................................5-20

• Cable and Configuration Guidelines ............................................5-21

• Hardware Planning Worksheets ....................................................5-24

Storage System Hardware 5-1

5


Server component

Unshared Direct

(one server)

Server

The storage systems attach to the server and the interconnect components described in Chapter 1.

Shared-or-Clustered Direct

(two servers)

Server Server

Shared Switched

(multiple servers)

Server Server

Server

Interconnect component

Storage component

FC loop 1

FC loop 2

Disk-array storage systems

Figure 5-1 Shared and Unshared Storage


5-2



5

Hardware for Shared Storage

The primary hardware component for shared storage is a ten-slot

Disk-array Processor Enclosure (DPE) with two storage processors

(SP). The DPE can support up to nine separate 10-slot enclosures called Disk Array Enclosures (DAEs) for a total of 100 disks. Shared storage requires two SPs and the Access Logix software option.

A DPE with a DAE is available as a deskside system, but with a capacity of 20 disks this cannot provide the expandability and total storage capacity needed for a SAN (storage area network). So this section does not cover the deskside version.

Storage Hardware — Rackmount DPE-Based Storage Systems

The DPE rackmount enclosure is a sheet-metal housing with a front door, a midplane, and slots for the storage processors (SPs), link control cards (LCCs), disk modules, power supplies, and fan packs.

All components can be replaced under power. The DPE rackmount model looks like the following figure.

Front Back

Power supplies

LCC

Link control card (LCC)

Disk modules (front door removed for clarity)

Storage processors (SPs)

FC ports with GBICs

Drive fan module

(detached for clarity)

Figure 5-2 DPE Storage-System Components – Rackmount Model

A separate standby power supply (SPS) is required to support write caching. All the shared storage components — rackmount DPE,

DAEs, SPSs, and cabinet — are shown in the following figure.

Hardware for Shared Storage 5-3

5


DAE

DAE

DPE

DAE

DAE

DPE

Disks

SPs

Standby power supplies (SPSs)

Front

Figure 5-3 Rackmount System with DPE and DAEs

Rear

EMC1744

The disks — available in differing capacities — fit into slots in the enclosure. Each module has a unique ID that you use when binding or monitoring its operation. The ID is derived from the enclosure address (always 0 for the DPE, settable on a DAE) and the disk module slot numbers.

5-4



5

Disk Modules and Module IDs — Rackmount DPE-Based System

10 11 12 13 14 15 16 17 18 19

0 1 2 3 4 5 6 7 8 9

Storage Processor (SP)

The SP provides the intelligence of the storage system. Using its own operating system (called Core Software), the SP processes the data written to or read from the disk modules, and monitors the modules themselves. An SP consists of a printed-circuit board with memory modules (DIMMs), and status lights.

For high availability, a storage system can support a second SP. The second SP provides a second route to a storage system and also lets the storage system use write caching for enhanced write performance. Two SPs are required for shared storage.

Server Server Server

Switch fabric

SP A SP B

Storage systems

Switch fabric

SP A SP B

Path 1

Path 2

Figure 5-4 Shared Storage Systems

See Chapter 3 for more examples of shared storage.

Hardware for Shared Storage 5-5

5


Hardware for Unshared Storage

Unshared storage systems are less costly and less complex than shared storage systems. They offer many shared storage system features; for example, you can use multiple unshared storage systems with multiple servers. However, with multiple servers, unshared storage offers less flexibility and security than shared storage, since any user with write access to privileged server files can enable access to any storage system.

Types of Storage System for Unshared Storage

For unshared storage, there are four types of storage system, each using the FC-AL protocol. Each type is available in a rackmount or deskside (office) version.

• Disk-array Processor Enclosure (DPE) storage systems. A DPE is a 10-slot enclosure with hardware RAID features provided by one or two storage processors (SPs). In addition to its own disks, a

DPE can support up to 110 additional disks in 10-slot Disk Array

Enclosures (DAEs) for a total of 120 disks. This is the same kind of storage system used for shared storage, but it uses a different storage processor (SP).

• Intelligent Disk Array Enclosure (iDAE). An iDAE, like a DPE, has SPs and thus all the features of a DPE, but is thinner and has a limit of 30 disks.

• Disk Array Enclosure (DAE). A DAE does not have SPs. A DAE can connect to a DPE or an iDAE, or you can use it without SPs. A

DAE used without an SP does not inherently include RAID, but can operate as a RAID device using software running on the server system. Such a DAE is also known as Just a Box of Disks, or

JBOD.

5-6



5

Disk-array processor enclosure (DPE)

Deskside DPE with DAE

Rackmount DPE, one enclosure, supports up to 9 DAEs

30-slot deskside

Intelligent disk-array enclosure (iDAE)

10-slot deskside Rackmount

Figure 5-5 Storage System Types for Unshared Storage

Hardware for Unshared Storage 5-7

5


Front

The following figure shows some components of a deskside DPE.

Components for rackmount types are similar.

Back (fans and cables omitted for clarity)

Storage processors

(SPs)

DAE link control

card (LCC)

DPE LCC

DAE power supplies

DPE power supplies

DPE

SP fan cover

(covers SP fan pack)

DAE

Front doors

(cover disk modules)

Power distribution

units

FC ports

DPE LCC

SPS units

DAE LCC

Figure 5-6 DPE Components - Deskside Model

Disks

enclosure. Each disk has a unique ID that you use when binding it or monitoring its operation. The ID is the enclosure address (always 0 for the DPE, settable on a DAE) and the disk slot number.

5-8



5

0

1

2

3

4

5

6

7

8

9

14

15

16

17

18

19

10

11

12

13

Figure 5-7 Disks and Disk IDs

0 1 2 3 4 5 6 7 8 9

Storage Processor (SP)

The SP provides the intelligence of the storage system. Using its own operating system (called Core Software), the SP processes the data written to or read from the disk modules, and monitors the modules themselves. An SP consists of a printed-circuit board with memory modules (DIMMs), status lights, and switches for setting FC-AL addresses.

For high availability, a storage system can support a second SP. A second SP provides a second route to a storage system, so both SPs can connect to the same server or two different servers, as follows.

Hardware for Unshared Storage 5-9

5


Server

Storage system

DAE(s)

SP A

DPE

SP B

Cables

FC loop 1

FC loop 2

Figure 5-8 Storage System with Two SPs Connected to the Same Server


Server 1 Server 2

Storage system

DAE(s)

SP A

DPE

SP B

FC loop 1

FC loop 2

Figure 5-9 Storage System with Two SPs Connected to Different Servers

Either SP can control any LUN in the storage system, but only one SP at a time can control a LUN. If one SP cannot access a LUN it controlled (because of a failure), you can transfer control of the LUN to the other SP, manually or via software.

5-10



5

Storage-system caching provides significant performance enhancement. Read caching is available with one or two SPs.

Mirrored write caching, particularly helpful with RAID 5 I/O, requires two SPs (to mirror one another, for cache integrity) and a

Standby Power Supply (SPS) to enable the SPs to write their cached data to disk if power fails.

Planning Your Hardware Components

This section helps you plan the hardware components — adapters, switches or hubs, cables, storage systems, and site requirements — for each server in your installation.

For shared storage, you must use a DPE rackmount system with two

SPs and high-availability options. We assume you have some idea of how many servers, adapters, switches or hubs, storage systems, and

SPs you want. Skip to the component data sheets following.

For unshared storage, you can use one or two SPs and you can choose among storage system configurations. This section assumes you have

examined the configurations shown starting on page 4-2 and have

some idea of how many servers, adapters, switches or hubs, storage systems, and SPs you want. It ends with blank worksheets and sample worksheets.

Configuration Tradeoffs - Shared Storage

The hardware configuration required for shared storage is very specific: two host-bus adapters in each attached server, two Fibre

Channel switches, and two SPs per storage system. Choices you can make with shared storage systems include the number of storage systems (up to 15 are allowed), and for each storage system the cache configuration (maximum or minimum), and one or two standby power supplies (SPS units).

The number of storage systems in the SAN depends on the servers’ processing demands. For each system, the larger cache improves write performance for very large processing loads; the redundant SPS lets write caching continue if one SPS fails.

Planning Your Hardware Components 5-11

5


Configuration Tradeoffs - Unshared Storage

For each storage-system enclosure, you have two important areas of choice: rackmount or deskside model, and high-availability options.

Generally, rackmount systems are more versatile; you can add capacity in a cabinet without consuming more floor space. However, rackmount systems require additional hardware, such as cabinets and mounting rails, and someone must connect power cords and cables within them. For large storage requirements, rackmount systems may be more economical than deskside systems. Deskside systems are more convenient; they ship with all internal cabling in place and require only ac power and connection to the servers.

For high availability, there are many variations. The most important high-availability features are a second SP/LCC pair, second power supply, and standby power supply (SPS). The second SP/LCC and

SPS let you use write caching to enhance performance; the second SP provides continuous access to storage-system disks if one SP or LCC fails. Another high-availability option is a redundant SPS.

Yet another option, for a deskside system, is a second power distribution unit (PDU), which lets you route ac power from an independent source. Used this way, the second PDU protects against failure in one of the two ac power sources. With a rackmount system, you can acquire a cabinet with one or two ac inlet cords. The second inlet cord, connected to a second ac power source, provides the same advantage for all storage systems in the cabinet as the second PDU in the deskside storage system.

For deskside systems, the optional high-availability hardware fits into the deskside cabinet. Deskside high-availability options are as follows.

5-12



5

Deskside

DPE

Table 5-1

Minimum

High-Availability Options, Deskside Unshared Storage

System Type HA Level PDUs SPs

1

LCCs

1 DAE

Power

Supplies

1 DPE

1 DAE

Disks

5 (without write cache) iDAE

DAE only

Maximum

Minimum

2 2 4 (2 DPE

2 DAE)

1 1 n/a

2 (30-slot)

Maximum 2 2 n/a

Minimum 1

Maximum 2 n/a n/a

4 (30-slot)

1

2

4

(2 DPE

2 DAE)

1

2 (10-slot)

6 (30-slot)

1

2

10 (write cache or RAID 3)

3 (without write cache)



No minimum

No minimum

SPS Units


1 (write cache)

2


1 (write cache

2 n/a n/a

Table 5-2

For rackmount systems, the standby power supply or supplies (SPS or BBU) must be placed in a tray directly beneath the storage system.

Typically, any hubs in the cabinet mount at the top or bottom of the cabinet. Rackmount options are as follows.

High-Availability Options, Rackmount Unshared Storage

Rackmount

System Type HA Level SPs

DPE Minimum 1

LCCs

1

Maximum 2 2 (DPE)

18 (with 9

DAEs) iDAE Minimum 1 (10-slot)

4 (with two

DAEs)

DAE only

Maximum 2

Minimum n/a

Maximum n/a n/a

1

2

2

1

2

Power

Supplies

1

2 (DPE)

11 (with 9

DAEs)

1

Disks


10 (write cache or

RAID 3)


5 (write cache or

RAID 3)

5 (write cache or

RAID 3)

No minimum

No minimum

SPS Units


1 (write cache)

2


1 (write cache

2 n/a n/a

Planning Your Hardware Components 5-13

5


Hardware Data Sheets

The hardware data sheets shown in this section provide the plant requirements, including dimensions (footprint), weight, power requirements, and cooling needs, for DPE, iDAE, DAE, and 30-slot

SCSI disk systems. Sections on cabinets and cables follow the data sheets.

DPE Data Sheet

Depth

74.7 cm

(30 in)

Deskside model

Width

52.1 cm

(20.6 in)

For shared storage, a rackmount DPE and one or more rackmount

DAEs are required. For unshared storage, you can use a rackmount or deskside DPE and DAE(s). The DPE dimensions and requirements are shown in the following figure.

DPE Dimensions and Requirements

Rackmount model

Depth

70 cm

(27.6 in)

Width

44.5 cm

(17.5 in)

Height

68 cm

(26.8 in)

Height

28.6 cm

(11.3 in)

6.5 U

Weight (without packaging)

Maximum (max disks, SPs,

LCCs, PSs): with 2 SPSs

SPS mounting tray height 4.44 cm

(1.75 in), 1 U; depth 54.1 cm

(21.3 in)

Deskside Rackmount

144 kg (316 lb) 52 kg (115 lb)

165 kg (364 lb) 74 kg (163 lb)

5-14



5

Power requirements

Voltage rating:

Current draw:

Power consumption:

100 V ac to 240 V ac –10%/+15%, single-phase, 47 Hz to 63 Hz; power supplies are auto-ranging

At 100 v ac input – Deskside

DPE/DAE: 12.0 A; Rackmount

DPE: 8.0 A max; SPS: 1.0 A max per unit during charge

Deskside DPE/DAE: 1200 VA;

Rackmount DPE: 800 VA max SPS:

1.0 A per unit during charge

Power cables (single or dual) ac inlet connector: IEC 320-C14 power inlet

Deskside power cord: USA: 1.8 m (6.0 ft):

NEMA 6-15P plug

Outside USA Specific to country

Operating environment

Temperature: 10 o

C to 40 o

C (50 o

F to 104 o

F)

Relative humidity:

Altitude:

Noncondensing, 20% to 80%

40 o

C to 2,438 m (8,000 ft); 37 o

C to 3,050 m

(10,000 ft)

Heat dissipation (max): Deskside DPE/DAE: 3931x10

3

J/hr (2730

BTU/hr) max estimated;

Rackmount DPE: 2520x10

3

J/hr (2390

BTU/hr) max estimated

Air flow: Front to back

Service clearances

Front:

Back:

30.3 cm (1 ft)

60.6 cm (2 ft)

Hardware Data Sheets 5-15

5


iDAE Data Sheet

Deskside 30-slot model

Depth

74.7 cm

(30 in)

Width

52.1 cm

(20.6 in)

You can use a rackmount or deskside DPE and DAE(s) for unshared storage. The iDAE dimensions and requirements are shown in the following figure.

Dimensions and Requirements, iDAE


Depth

74.7 cm

(30 in)

Width

25 cm

(9.8 in)

Rackmount model

Depth

63.3 cm

(24.9 in)

Width

44.5 cm

(17.5 in)

Height

68 cm

(26.8 in)

SPS mounting tray, height 4.44 cm

(1.75 in), 1 U; depth 69.9 cm

(27.5 in)

Height

15.4 cm

(6.1 in)

3.5 U


Maximum (max disks, SPs):

Deskside 30 Deskside 10 Rackmount

144 kg (316 lb) 60 kg (132 lb) 35.4 kg (78 lb)


Voltage rating:

Current draw:

Power consumption:

100 V ac to 240 V ac +/- 10%, single-phase,

47 Hz to 63 Hz; power supplies are auto-ranging

At 100 v ac input – 30-slot 12.0 A; 10-slot: 4.0

A; SPS: 1.0 A max per unit during charge

30-slot: 1200;10-slot: 400 VA; SPS: 100 VA per unit during charge

5-16



5


Deskside power cord: USA: 1.8 m (6.0 ft): NEMA

6-15P plug

Outside USA: Specific to country


Temperature:

Relative humidity:

Altitude:

10 o C to 40 o C (50 o F to 104 o F)


40 o C to 2,438 m (8,000 ft); 37 o C to 3,050 m

(10,000 ft)

Heat dissipation (max): 30-slot: 4,233 KJ/hr (4,020 BTU/hr)

10-slot: 1,411 KJ/hr (1,340 BTU/hr)


Service clearances

Front:

Back:

30.3 cm (1 ft)

60.6 cm (2 ft)


5


DAE Data Sheet


Depth

74.7 cm

(30 in)

Width

52.1 cm

(20.6 in)

The DAE storage-system dimensions and requirements are shown in the following figure.

Dimensions and Requirements, DAE


Width

25 cm

(9.8 in) Depth

74.7 cm

(30 in)

Rackmount model

Depth

63.3 cm

(24.9 in)

Width

44.5 cm

(17.5 in)

Height

68 cm

(26.8 in)

Height

15.4 cm

(6.1 in)

3.5 U


Maximum (max disks, SPs)

Deskside 30 Deskside 10 Rackmount

144 kg (316 lb) 60 kg (132 lb) 35.4 kg (78 lb)


Voltage rating:

Current draw:

Power consumption:

100 V ac to 240 V ac +/- 10%, single-phase,

47 Hz to 63 Hz; power supplies are auto-ranging

At 100 v ac input – 30-slot 12.0 A; 10-slot: 4.0

A; SPS: 1.0 A max per unit during charge*

30-slot: 1200;10-slot: 400 VA; SPS: 1.0 VA per unit during charge

5-18



5


Deskside power cord: USA: 1.8 m (6.0 ft): NEMA

6-15P plug

Outside USA: Specific to country


Temperature:

Relative humidity:

Altitude:

10 o C to 40 o C (50 o F to 104 o F)


40 o C to 2,438 m (8,000 ft); 37 o C to 3,050 m

(10,000 ft)

Heat dissipation (max): 30-slot: 4,233 KJ/hr (4,020 BTU/hr)

10-slot: 1,411 KJ/hr (1,340 BTU/hr)


Service clearances

Front:

Back:

30.3 cm (1 ft)

60.6 cm (2 ft)


5


Cabinets for Rackmount Enclosures

Prewired 19-inch-wide cabinets, ready for installation, are available in the following dimensions to accept rackmount storage systems.

Vertical Space Exterior Dimensions Comments

173 cm or 68.25 in

(39 NEMA units or

U; one U is 1.75 in)

Height: 192 cm (75.3 in)

Width: 65 cm (25.5 in)

Depth: 87 cm (34.25 in) plus service clearances, which are 90 cm (3 ft),

30 cm front and 60 cm back

Accepts combinations of:

DPEs at 6.5 U, iDAEs at 3.5 U,

SPS units at 1 U,

DAEs at 3.5 U each,

Switches or hubs at 1 U

Weight (empty): 134 kg (296 lb)

Requires 200–240 volts ac. Plug options include L6–30 or L7–30 (domestic) and

IEC 309 30 A (international).

Each power strip has 12 IEC-320 CIS outlets.

Filler panels of various sizes are available.

As an example, a rackmount storage system that supports 100 disk modules has the following requirements.

Category

Vertical cabinet space in

NEMA units (U, one U is

1.75 in)

Weight

Power

Cooling

Requirement

Bottom to top: One SPS (1 U), one DPE (6.5 U), and nine DAEs (9*3.5 U equals 31.5 U) for a total of 39 U.

516 kg (1,137 lb) including the cabinet (134 kg), DPE (52 kg), SPS (11 kg), and nine DAEs (9 * 35.4 kg equals 319 kg).

4,500 VA max, including the DPE (800 VA), SPS (100 VA), and nine DAEs

(9 * 400 VA equals 3600 VA).

15,484 KJ/hour (14,700 BTU/hr), including the DPE (2,520

KJ/hr), SPS (265 KJ/hour, estimated), and nine DAEs (9*1,411 KJ/hr equals

12,699 KJ/hr).

5-20



5

Cable and Configuration Guidelines

We recommend that all copper-interconnected nodes be connected to a common ground grid. The common grid is not needed for optical interconnections.

Copper cable allows up to 30 meters (99 feet) between nodes or switches and hubs. Optical cable allows significantly longer distances. This is a major advantage of optical cable. However, you can use optical cable from a server only if the server’s adapter supports optical cable; otherwise you must use copper. Not all adapters support optical cable.

To connect a DPE to a DAE, you must use copper cable, whose maximum length is 10 meters (33 ft). So, the distance between a DPE and the DAEs it controls cannot exceed 10 meters (33 ft).

The host-bus adapters and SPs used with shared storage systems require optical cable, as does the switch between adapters and SPs.

The SPs used with unshared storage systems support copper cables and — with MIAs — optical cables. A hub itself supports copper, or with a MIA, optical. So you can use a copper cable or — with two

MIAs per cable — optical cable between any hub and SP. For optical cable to work between an adapter and hub or SP, then the adapter must support optical cable.

Server Server

Maximum distance:

Copper cable: 30 m

Optical cable:500 m or more

Switch or hub

Maximum distance:

Copper cable: 30 m

Storage system Storage system

Figure 5-10 Comparison Between Optical and Copper Cabling

Cable and Configuration Guidelines 5-21

5


Table 5-3

You can use any existing FDDI, multimode, 62.5 micron cable with good connections to attach servers, switches or hubs, and storage systems. These cables must be dedicated to storage-system I/O.

Cable Sizes — Optical

Length

5 m (16.5 ft) or

10 m (33 ft)

Typical Use

Within one room, connecting servers to storage systems (adapter must support optical cable) or connecting switches or hubs to storage systems

50 m (164 ft)

100 m (328 ft)

250 m (821 ft,.15 mi)

500 m (1642 ft,.31 mi)

Within one building, connecting servers to storage systems (adapter must support optical cable) or connecting switches or hubs to storage systems

Within one complex, connecting servers to storage systems (adapter must support optical cable) or connecting switches or hubs to storage systems

Optical cabling is 50 micron (maximum length is 500 m —1,650 ft —, or

62.5 micron (maximum length is 300 m — 985 ft. Both types are multimode, dual SC, and require a MIA on a DB-9 or hub connector. The minimum length is 2 m (6.8 ft). The minimum bend radius is 3 cm (1.2 in).

5-22



5

Table 5-4 Cable Sizes — Copper

Length

0.3 m (1 ft), non-equalized

1.0 m (3.3 ft), non-equalized

3 m (10 ft), non-equalized

Typical Use

Connecting DPE/DAE and DAE LCCs

Connecting a hub to an adjacent storage system

Connecting a hub to a storage system in the same cabinet, or daisy chaining from one cabinet to an adjacent cabinet

5 m (16.5 ft), non-equalized

10 (33 ft), non-equalized

Connecting a hub in one rack to a storage system in another cabinet

Connecting servers to hubs and/or storage systems — maximum length for non-equalized copper cable, maximum length between LCCs

30 m (98.5 ft), equalized Connecting servers to hubs and/or storage systems – maximum length for copper cable

Copper cabling is shielded, 75-ohm twin-axial, shield bonded to DB-9 plug connector shell (360 o ) FC-AL

Standard, Revision 4.4 or higher.

Component planning diagrams and worksheets follow.

Cable and Configuration Guidelines 5-23

5


Hardware Planning Worksheets

Following are worksheets to note the hardware components you want. There are two types of configuration:

• Shared storage

• Unshared storage

Hardware for Shared Storage

A1

Server 1

A1

Server n

. . .

An An

Path 1

Path 2

Switch 1

D1

E2

E1

Dm

E2

E1

DAE

DAE

DPE

SP B SP A

Storage system 1

DAE

DAE

DPE

SP B SP A

Storage system m

E2

E1

D1

E2

E1

Dm

Switch 2

Figure 5-11 Cable Identifier — DPE-Based System for Shared Storage

The cable identifiers used above apply to shared and unshared storage systems. The worksheet applies to shared storage only.

5-24



5

Hardware Component Worksheet for Shared Storage

Number of servers:____ Adapters in servers:____ Switches: 16-port:____8-port:____

Rackmount DPEs:_____SP/LCC pairs:_____PSs:_____SPSs:____ Rackmount cabinets:___

Rackmount DAEs:_____ LCCs:_____PSs:_____

Cables between server and switch - Cable A, optical only

Cable A

1,

Cable A

2,

Optical: Number:____ ....................................................... ..............Length________m or ft

Optical: Number:____ ....................................................... ..............Length________m or ft

Cable A n

, Optical: Number:____ ...................................................... ..............Length________m or ft

Cables between switches and storage systems - Cable D, copper or optical

Cable D

1,

Optical:Number:_____ ...................................................... ..............Length________m or ft

Cable D

2,

Optical:Number:_____ ...................................................... ..............Length________m or ft

Cable D m,

Optical:Number:_____ ..................................................... ..............Length________m or ft

Cables between enclosures - Cable E, which connects LCCs; between a DPE LCC and a DAE LCC, Cable

E must be copper; between DAE LCCs, it can be copper or optical.

Cable E

1

Cable E

2

:Number:_____

V

Copper

V

Optical(for DAE to DAE only). ..............Length________m or ft

:Number:_____ V Copper V Optical(for DAE to DAE only) ..............Length________m or ft

Hardware Planning Worksheets 5-25

5



File Server Mail Server Database Server

Switch 1 Switch 2

A2 Cable between server and switch

D1

Cable between switch and storage system

Path 1

Path 2

DAE

DAE

DAE

DAE

DAE

DAE

DPE

SP B SP A

Storage system

Figure 5-12 Sample Shared Storage Installation

E1

Cable between storage systems or enclosures

5-26



5

Hardware Component Worksheet for Shared Storage

Number of servers:__ 3 _ Adapters in servers:__ 6 _ Switches: 16-port:____8-port:__ 2

Rackmount DPEs:__ 1 ___SP/LCC pairs:__ 2 ___PSs:___ 2 __SPSs:__ 2 __ Rackmount cabinets:_ 1 __

Rackmount DAEs:__ 6 ___ LCCs:___ 12 __PSs:___ 12 __

Cables between server and switch - Cable A, optical only

Cable A

1,

Optical: Number:_____ ...................................................... ............. Length______m or ft

Cable A

2,

Optical: Number:__ 4 __ ..................................................... ............. Length__ 33 _m or ft

Cable A n

, Optical: Number:____ ....................................................... ............. Length______m or ft

Cables between switches and storage systems - Cable D, copper or optical

Cable D

1,

Optical:Number:__ 2 ___ .................................................... ............. Length___ 33 __m or ft

Cable D

2,

Cable D m,

Optical:Number:_____ ...................................................... ............. Length________m or ft

Optical:Number:_____ ...................................................... ............. Length________m or ft

Cables between enclosures - Cable E, which connects LCCs; between a DPE LCC and a DAE LCC, Cable

E must be copper; between DAE LCCs, it can be copper or optical.

Cable E

1

Cable E

2

:Number:__ 12 ___ V Copper V Optical(for DAE to DAE only) ......... Length____ 1 ___m or ft

:Number:_____ V Copper V Optical(for DAE to DAE only). ............. Length________m or ft

Hardware for Unshared Storage

The cable identifiers used in the following figure and on the following worksheets apply to all types of unshared storage systems.

So, if you want to plan a site with different types of systems, you can consolidate all your unshared storage component entries (from the different system types on a single worksheet).


5


A1

Server 1

A1

Server 2

A2 A2

DAE

FC Loop 1

FC Loop 2

E2

E1

DAE iDAE/DPE

SP B SP A

Storage system

E2

E1

Figure 5-13 Cable Identifier — Unshared System without Hubs

5-28



5

A1

Server 1

A1

Server n

. . .

An

Hub 1 Hub 2

DAE

D1

E2

E1

Dm

DAE iDAE/DPE

SP B SP A


DAE

E2

E1

D1

Dm

FC Loop 1

FC Loop 2

E2

E1

DAE iDAE/DPE

SP B SP A

Storage system m

E2

E1

Figure 5-14 Cable Identifier — Unshared Full-Fibre System with Hubs

An


5


Hardware Component Worksheet for Unshared Storage

Number of servers: Adapters in servers:______ Hubs (copper):_____ MIAs (copper to optical):______

DPE-based and DAE-only storage systems:

Rackmount DPEs:_____SP/LCC pairs:_____

Rackmount iDAEs:_____SPs:_____

PSs:_____SPSs:____ Rackmount cabinets:___


Rackmount DAEs:_____ LCCs:_____PSs:_____

Deskside DPEs:_____SP/ LCC pairs:_____DAE LCCs:____ DPE PSs:____ DAE PSs:____ SPSs:__

Deskside iDAEs:_____SPs:_____ DAE LCCs:____ PSs:____ SPSs:___

Deskside DAEs: 30-slot_____ 10-slot______ LCCs:_____ PSs:_____

Cables between server and storage system or between server and hub - Cable A, copper or optical

Cable A

1

:Number:____ V Copper V Optical ...................................... ............. Length________m or ft

Cable A

2

Cable A n

:Number:____ V Copper V Optical..................................... ............. Length________m or ft

:Number:____ V Copper V Optical..................................... ............. Length________m or ft

Cables between hubs and storage systems - Cable D, copper or optical

Cable D

1

Cable D

2

Cable D m

:Number:_____ V Copper V Optical ..................................... ............. Length________m or ft

:Number:_____ V Copper V Optical ..................................... ............. Length________m or ft

:Number:_____ V Copper V Optical..................................... ............. Length________m or ft

Cables between storage systems or enclosures - Cable E, which connects LCCs or SP-LCC; between a

DPE LCC or iDAE SP and a DAE LCC, Cable E must be copper; between DAE LCCs, it can be copper or optical.

Cable E

1

Cable E

2

:Number:_____ V Copper V Optical(DAE to DAE only)........ ............. Length________m or ft

:Number:_____ V Copper V Optical(DAE to DAE only)........ ............. Length________m or ft

*Please specify all storage-system components you need, even though you will not need to order them separately, since most or all components will be included with the model of each system you order.

5-30



5

Server

A1 Cable between server

and storage system

A1

E1

DAE

E1 Cable between storage

systems or enclosures

Included with deskside

DPE iDAE/DPE

SP A

Figure 5-15 Sample Unshared Deskside System — Basic Configuration

Sample Component Worksheet


Number of servers: 1 Adapters in servers:___ 1 ___ Hubs (copper):______ MIAs (copper to optical):_____



Rackmount iDAEs:__ 1 ___SPs:__ 1 ___


PSs:___ 1 __SPSs:____ Rackmount cabinets:__ 1 _

Rackmount DAEs:___ 1 __ LCCs:__ 1 ___PSs:__ 1 ___





Cable A

1

:Number:__ 1 __ V Copper V Optical ................................... ..............Length__

1 0 __ _m or ft

Cable A

2

Cable A n

:Number:____ V Copper V Optical .................................... ..............Length________m or ft

:Number:____ V Copper V Optical .................................... ..............Length________m or ft


Cable D

1

Cable D

2

Cable D m

:Number:_____ V Copper V Optical..................................... ..............Length________m or ft

:Number:_____ V Copper V Optical..................................... ..............Length________m or ft

:Number:_____ V Copper V Optical .................................... ..............Length________m or ft



Cable E

1

Cable E

2

:Number:__ 1 __ V Copper V Optical(DAE to DAE only)....... ..............Length__

1 _____m or ft

:Number:_____ V Copper V Optical(DAE to DAE only) ..... Length________m or ft


5


Server

E1

A1 Cable between

server and storage

system



included with deskside DPE



A1

DAE

DAE

DAE

E2

DAE

DPE

SP B SP A

Storage system

FC Loop 1

FC Loop 2

Figure 5-16 Sample Unshared Deskside System — Dual-Adapter/Dual-SP

Configuration

5-32



5

Sample Component Worksheet


Number of servers: 1 Adapters in servers:__ 2 __ Hubs (copper):______ MIAs (copper to optical):_______



Rackmount iDAEs:_____SPs:_____

Rackmount DAEs:_____



LCCs:_____PSs:_____

Deskside DPEs:__ 1 _SP/ LCC pairs:__ 2 __DAE LCCs:__ 2 __ DPE PSs:_ 2 _ DAE PSs:_ 2 _ SPSs:_ 1 _


Deskside DAEs: 30-slot__ 1 ___ 10-slot______ LCCs:__ 6 ___ PSs:__ 6 __


Cable A

1

:Number:_ 2 _ V Copper V Optical ...................................... ............. Length___ 10 ___m or ft

Cable A

2

Cable A n

:Number:____ V Copper V Optical .................................... ............. Length________m or ft

:Number:____ V Copper V Optical .................................... ............. Length________m or ft


Cable D

1

Cable D

2

Cable D m

:Number:_____

V

Copper

V

Optical..................................... ............. Length________m or ft

:Number:_____ V Copper V Optical..................................... ............. Length________m or ft

:Number:_____ V Copper V Optical .................................... ............. Length________m or ft



Cable E

1

:Number:__ 6 ___ V Copper V Optical(DAE to DAE only)...... ............. Length___ 1 ____m or ft

Cable E

2

:Number:__ 2 ___ V Copper V Optical(DAE to DAE only)...... ............. Length___ 5 ____m or ft


5


Server 1 Server 2

Cable between server and hub

A1

A2 Cable between server and hub

A2

Hub 1 Hub 2

Cable between hub and storage system

D2

FC Loop 1

FC Loop 2

D1

DAE

DAE

DAE

DAE

DPE

SP B SP A


DAE

DAE

DAE

DAE

DPE

SP B SP A


E1

Cable between storage systems or enclosures

D2

D1

Cable between hub and storage system

Figure 5-17 Sample Component Worksheet for DPE-Based System with Hubs — Two

Loops

5-34



5


Number of servers: 2 Adapters in servers:___ 4 ____ Hubs:___ 2 ____ MIAs (optical to copper):_______


Rackmount DPEs:_____SP/LCC pairs:__ 4 ___ PSs:___ 4 __SPSs:_ 2 __ Rackmount cabinets:_ 2 __

Rackmount iDAEs:_____SPs:_____ PSs:_____SPSs:____ Rackmount cabinets:___

Rackmount DAEs:__ 8 ___ LCCs:__ 16 _PSs:__ 16 ___





Cable A

1

:Number:__ 2 _

V

Copper

V

Optical ..................................... ..............Length_

20 _____m or ft

Cable A

2

Cable A n

:Number:__ 2 __ V Copper V Optical ................................. ..............Length_

1 0 _____m or ft

:Number:____ V Copper V Optical.................................... ..............Length________m or ft


Cable D

1

:Number:__ 2 __ V Copper V Optical .................................... ..............Length__

20 __ _m or ft

Cable D

2

:Number:__ 2 __ V Copper V Optical .................................... ..............Length___

20 ___m or ft

Cable D m

:Number:_____ V Copper V Optical.................................... ..............Length________m or ft



Cable E

1

Cable E

2

:Number:_ 16 __ V Copper V Optical(DAE to DAE only)....... ..............Length___

1 ____m or ft

:Number:_____ V Copper V Optical(DAE to DAE only)....... ..............Length________m or ft

Please specify all storage-system components you need, even though you will not need to order them separately, since most or all components will be included with the model of each system you order.

What Next?

This chapter explained hardware components of shared and unshared storage systems. If you have completed the worksheets to your satisfaction, you are ready to consider ordering some of this equipment. Or you may want to read about storage management in the next chapter.


5


5-36


6

Storage-System

Management

This chapter explains the management applications you can use to manage storage systems from servers. Topics are

• Using Navisphere Manager Software .............................................6-3

• Storage Management Worksheets ...................................................6-5

Storage-System Management 6-1

6


Navisphere software lets you bind and unbind disks, manipulate caches, examine storage-system status and logged events, transfer control from one SP to another, and examine events recorded in storage system event logs.

Navisphere products have two parts: a graphical user interface (GUI) and an Agent application. The GUIs run on a management station, accessible from a common framework, and communicate with storage systems through the Agent that runs on each server. The

Navisphere products are

• Navisphere Manager, which lets you manage multiple storage systems on multiple servers simultaneously;

• Navisphere Analyzer, which lets you measure, compare, and chart the performance of SPs, LUNs, and disks.

• Navisphere Integrator, which provides an interface between

Navisphere products and HP OpenView, CA Unicenter, and

Tivoli.

• Navisphere Event Monitor, which checks storage systems for fault conditions and can notify you and/or customer service if any fault condition occurs.

• Navisphere failover software. Application-Transparent Failover

(ATF) is an optional software package for high-availability installations. ATF software lets applications continue running after the failure anywhere in the path to a LUN: a host-bus adapter, cable, switch, or SP. ATF is required for any server that has two host-bus adapters connected to the same storage system.

Another failover product is CDE (Driver Extensions) software, which has limited failover features. CDE is included with each host-bus adapter driver package.

• Navisphere Agent, which is included with each storage system, and Navisphere CLI (Command Line Interface), which lets you bypass the GUI and type commands directly to storage systems.

The Agent runs on any of several different platforms, including

Windows and popular UNIX® platforms; the other products run on

Windows platforms only.



6

Using Navisphere Manager Software

Navisphere Manager software (Manager) lets you manage multiple storage systems connected to servers on a TCP/IP network. Manager offers extensive management features and includes comprehensive on-line help. Manager is required for shared storage and optional for unshared storage.

Manager runs on a management station which is a Windows NT

®

or

Windows

®

2000 host. The servers connected to a storage system can run Windows or one of several UNIX® operating systems. With shared storage, servers connected to the SAN can run different operating systems; with direct (unshared direct or shared-or-clustered) storage, servers connected to the same storage system must run the same operating system.

The following figures show Navisphere Manager in shared and unshared environments.

Using Navisphere Manager Software 6-3

6


File Server

Management station and server

Operating system A

Navisphere

Manager

Navisphere

Agent

Failover

software

Mail Server


Operating system A

Navisphere

Manager

Navisphere

Agent

Failover

software

Switch fabric

Database Server

Operating system B

Navisphere

Agent

Failover

software

Switch fabric

Production Server

Operating system C

Navisphere

Agent

Failover

software

LAN

Path 1

Path 2

Figure 6-1 Sample Shared Switched Environment with Navisphere Manager

Accts Server


Operating system A

Navisphere

Supervisor

Navisphere

Agent

Database Server

Operating system B

Navisphere

Agent

Development Server


Operating system C

Navisphere

Supervisor

Navisphere

Agent

LAN

6-4

Figure 6-2 Sample Unshared Environment with Navisphere Manager

EMC Fibre Channel Storage-System Configuration Planning


6

Storage Management Worksheets

This section includes two worksheets: one for shared storage and one for unshared storage. The following worksheet will help you plan your storage system management environment. For each host, complete a section.

For the shared storage worksheet, complete the management station hostname and operating system; then decide whether you want the

Navisphere Analyzer and/or Event Monitor and, if so, mark the appropriate boxes. Then write the name of each managed server, with operating system, Storage Group, and configuration access specification. You can copy much of the needed information from the

LUN and Storage Group planning worksheet in Chapter 3 or 4.

Management Utility Worksheet – Shared Storage

Management station hostname:___________________Operating system:_______________

Software: V Navisphere Manager/Agent V Navisphere Analyzer V Navisphere Event Monitor

List all the servers this host will manage. Each managed server must run an Agent and ATF software of the same type as its operating system.

Server: Op sys: Storage Group number or name:

Server:

Server:

Op sys:

Op sys:

Storage Group number or name:


Server:

Server:

Server:

Server:

Server:

Op sys:

Op sys:

Op sys:

Op sys:

Op sys:






V

V

V

Config Access

Config Access

Config Access

V Config Access

V Config Access

V Config Access

V Config Access

V Config Access

Management station hostname:___________________Operating system:_______________


List all the servers this host will manage. Each managed server must run an Agent and ATF software of the same type as its operating system.

Server: Op sys: Storage Group number or name:

Server:

Server:

Op sys:

Op sys:



Server:

Server:

Server:

Server:

Server:

Op sys:

Op sys:

Op sys:

Op sys:

Op sys:






V

V

V

Config Access

Config Access

Config Access

V Config Access

V Config Access

V Config Access

V Config Access

V Config Access

Storage Management Worksheets 6-5

6


For unshared storage (unshared direct or shared-or-clustered direct), for each host, choose a Navisphere product. The host may be a management station that is not a server (complete only the Manager section); it may be a management station that is a server (complete the Manager section and mark the Agent box), or it may be a server

(mark the Agent box).



6

Management Utility Worksheet – Unshared Storage

Hostname:

Storage system type: V DPE-based

Operating system:

V iDAE-based


List all the servers this host will manage. Each managed server must run an Agent of the same type as its operating system.

Server: Oper sys: Server: Oper sys:

Server:

Server:

Server:

Oper sys:

Oper sys:

Oper sys:

Server:

Server:

Server:

Oper sys:

Oper sys:

Oper sys:

Hostname: Operating system:

Storage system type: V DPE-based V iDAE-based

Software: V Navisphere Manager and Navisphere Agent V Navisphere Agent and CLI



Server:

Server:

Server:

Oper sys:

Oper sys:

Oper sys:

Server:

Server:

Server:

Oper sys:

Oper sys:

Oper sys:

Hostname: Operating system:

Storage system type: V DPE-based V iDAE-based

Software: V Navisphere Manager and Navisphere Agent V Navisphere Agent and CLI



Server:

Server:

Oper sys:

Oper sys:

Server:

Server:

Oper sys:

Oper sys:


Storage Management Worksheets 6-7

6



Index

A ac power requirements

DAE-only storage system 5-18

DPE storage system 5-14

iDAE storage system 5-16

application planning

shared storage 3-6

unshared storage 4-4

application worksheet, completing

shared 3-6, 4-4 unshared or clustered direct 4-4

applications

for RAID Groups, sample 2-19

LUN and file system

planning 3-6

application-transparent failover (ATF) software

6-2

array, see disk-array storage system attach kit, see host-bus adapter driver package

audience for manual xi

C

cabinets for rackmount storage systems 5-20

cabling

guidelines 5-21

introduced 1-4

types and sizes 5-22

cache

about 5-11

page size 4-13

cascading switches 1-6

CDE driver extensions software 6-2

CLI (Command Line Interface) 6-2

clustered installation, disk structure example 4-3

communication with storage system, see Chapter

6

configurations

RAID

compared 2-12

examples 4-2

planning 3-6

RAID types

guidelines 2-17

shared storage

examples 3-3

tradeoffs 5-12

unshared storage

examples 4-2 installation 4-2

cooling requirements

cabinet 5-20

DAE 5-19

DPE 5-15

iDAE 5-17

copper cable, types and sizes 5-23

CRUs (customer-replaceable units)


locating 5-8

SP 5-5, 5-9

D

DAE, see also Disk Array Enclosure (DAE)

DAE-only storage systems

dimensions 5-18

introduced 1-16, 5-6


i-1

Index i-2

site requirements 5-18 weight 5-18

data sheets, hardware 5-14

device name, operating system 3-16, 4-15

disk capacity

defined 4-14

capacity, defined 4-13

configuration types

compared 2-12

configuration, see also RAID Group

IDs 3-4, 4-2

LUN types

planning 3-6

mirror, defined 2-2

number on worksheet 4-14

RAID types

guidelines 2-17

sample applications 2-19

shared storage

examples 3-3

striping, defined 2-2

unit number on worksheet 3-8, 4-13

unshared storage

example 4-2 examples 4-2

Disk Array Enclosure (DAE)

introduced 5-6

site requirements 5-18

Disk Array Processor Enclosure (DPE)

introduced 5-6

Disk Array Processor Enclosure (DPE), see DPE storage system

disk-array storage system

communicating with, see Chapter 6

hardware

shared storage 1-15


installation types 1-10

managing, see Chapter 6

DPE storage systems

components 5-3

dimensions 5-14 site requirements 5-14 weight 5-14

driver extensions software (CDE) 6-2

dual paths to LUNs 3-2, 4-2


E enclosure address (EA)

DPE 5-4, 5-8

F fabric, switch

introduced 1-3

Fibre Channel

adapter 1-4 components 1-4

defined 1-3

hub, description 1-8

switch, description 1-5 switch, see switch

file system

name 3-17, 4-15

worksheet

completing 3-13, 4-12

footprint


DPE storage systems 5-14

iDAE storage systems 5-16

rackmount cabinet 5-20

G

GBIC (Gigabit Interface Converter), about 1-5

global spare, see hot spare

grounding requirements 5-21

GUI (in storage-system management utilities) 6-3

H hardware

data sheets 5-14

mirroring 2-2

planning worksheets

shared storage 5-24

shared storage 1-15, 5-3


heat dissipation




height

DAE-only storage systems 5-18


iDAEstorage system 5-16

high availability

options for unshared storage 5-13

shared switched instllation 1-10

host, see also server

host-bus adapter (HBA), introduced 1-4 host-bus adapter driver package 1-4

hot spare

defined 2-9


when to use 2-18

hub

description 1-8

planning system with 5-29

sample hardware worksheet 5-34

I iDAE storage systems

dimensions 5-16 site requirements 5-16 weight 5-16

image, disk, defined 2-2

individual access array, see RAID 5 Group

individual disk unit

defined 2-9

disk space usage 2-16

performance 2-14


when to use 2-18


tradeoffs 5-11

intelligent Disk Array Enclosure (iDAE), see iDAE storage systems

interconnect components 5-1

cables, hubs, switches 1-4

interface kit, see host-bus adapter driver package

L

LCC (link control card) 5-8

logical volume, see file system

LUN (logical unit) configurations

individual disk, defined 2-9

RAID 0, defined 2-8

RAID 1 mirrored pair 2-7

RAID 1/0 Group

defined 2-8

RAID 3 Group, defined 2-5

RAID 5 Group, defined 2-4

shared storage, examples 3-3

disk mirror, defined 2-2

in RAID Group 2-3

number on worksheet 3-8, 3-15, 4-13, 4-14

paths to 3-2, 4-2

planning 3-6

RAID types

compared 2-12

guidelines 2-17


SP control of 5-10

unshared storage

examples 4-2 unshared, examples 4-2

worksheets 3-13, 4-10, 4-12

M

Manager utility 6-2

manual, about 1-xi

MIA (media interface adapter), about 1-5

mirrored pair, see RAID 1 mirrored pair mirrored RAID 0 Group, see RAID 1/0 Group

mirroring, defined 2-2

N

Navisphere Manager utility 6-2

node, defined 1-3

nonredundant array, see also RAID 0 Group

O operating system

device name for disk unit 4-15

device name for LUN 3-16

software mirroring 2-2

optical cable, types and sizes 5-22

organization of manual xii

Index


i-3

Index i-4

P

page size, cache 3-14, 4-13

parallel access array, see RAID 3 Group

paths to LUNs 3-2, 4-2

performance, RAID Group 2-13

physical disk unit, see LUN (logical unit) physical volume, see LUN (logical unit)

planning LUNs and file systems 3-6

plant requirements

DAE 5-18

iDAE 5-16

plug types 5-20

power requirements


DPEstorage system 5-14


power supplies (PSs), DPE storage system 5-8

R rackmount model DPE storage system

DPE storage system

rackmount model 5-3

RAID Group configurations

compared 2-12

performance 2-13

planning 3-6

RAID types

guidelines 2-17


RAID 3 versus RAID 5 2-6

shared storage

examples 3-3

types and tradeoffs, see Chapter 2

unshared storage

examples 4-2

RAID Groups and LUNs 2-3

RAID types

guidelines 2-17


RAID 0 Group

defined 2-8


when to use 2-18

RAID 1 mirrored pair

defined 2-7



when to use 2-17

RAID 1/0 Group

defined 2-8


when to use 2-17

RAID 3 Group

defined 2-5


when to use 2-17

RAID 5 Group

defined 2-4


when to use 2-17

redundant array of independent disks (RAID), see

RAID Group

S server

cabling guidelines 5-21

component 5-1

connection to storage system, see cabling

planning worksheet


unshared storage example 4-2

service clearance


iDAEstorage system 5-17

shared storage

components 5-3

disk structure example 3-3

hardware 1-15

switched, defined 1-10

shared storage systems

cabinets 5-20

hardware planning worksheets 5-24

shared-or-clustered direct installation

defined 1-10

disk structure example 4-2, 4-3

site requirements

DAE 5-18


DPE storage systems 5-14

iDAE storage systems 5-16

size, cache 3-14, 4-13

software mirroring, defined 2-2

SP (storage processor)

description 5-5, 5-9

FC-AL address ID 3-14, 4-12

SPS (standby power supply)


storage components

shared storage 5-3

storage managment worksheets 6-5

storage system caching

on worksheet 4-14

storage-system caching

as feature 5-11

stripe

with RAID 1/0, RAID 0 2-8

with RAID 5, RAID 3 2-4

stripe, defined 2-2

switch

description 1-5

in sample shared storage configuration 3-3

introduced 1-3

switch fabric

introduced 1-3

T temperature requirements




terms, RAID 2-2

tradeoffs


RAID types 2-12

U unshared direct installation

defined 1-10


unshared storage


hardware 1-16

hardware planning worksheets 5-27


V

vault disks 2-10

volume, name 3-17

W weight




storage system installation 5-20

worksheet

application 3-6 completing 3-6

component planning


LUN 3-13, 4-10, 4-11, 4-12

worksheets component planning

shared storage 5-24


storage management 6-5

Index


i-5

Index i-6


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