Seagate ST39103LC Guida Utente

Part Number:313433501Shared Virtual ArraySVA PathVersion 3.1HP-UXUser’s Guide

x SVA Path User’s Guide

Chapter 1. SVA Path Overview 1Chapter 1. SVA Path OverviewThis chapter provides an overview of SVA Path Intelligent Data Path Management software a

2 SVA Path User’s Guide1. by allowing SVA Path to uniformly distribute primary paths among all available I/O paths. This is the default behavior of SV

Chapter 1. SVA Path Overview 3Supported SVA Path ConfigurationsSVA Path supports single server configurations.SystemRequirementsBefore proceeding t

4 SVA Path User’s GuideSummary of SVA Path Benefits• Increases potential subsystem throughput by directing I/O through multiple host adapters and SVA

Chapter 2. SVA Path Hardware Setup 5Chapter 2. SVA Path Hardware SetupFibre Addressing ConceptsHost BusAdapters/InitiatorsThe terms “host bus adapt

6 SVA Path User’s GuideFigure 2-1 shows two data paths connecting the open systems platform to the attached SVA using Fibre cables.Figure 2-1 Fibre Pa

Chapter 2. SVA Path Hardware Setup 7Domain Numberingwith Fibre andSVA PathIt is not normally advisable to have more than one path from a single hos

8 SVA Path User’s GuideConfiguration in a Mixed SCSI/Fibre EnvironmentFailover can only be accomplished from one SCSI interface to another, or from on

Chapter 2. SVA Path Hardware Setup 9Hardware PreparationConfiguring an HPSystem to See NewDevicesPerform the following steps on the HP host:Note:

Proprietary Information StatementThe information in this document is confidential and proprietary to Storage Technology Corporation and may be used on

10 SVA Path User’s GuideFigure 2-3 Example format Output for a Dual -Path SystemClass I H/W Path Driver S/W State H/W Type De

Chapter 3. SVA Path Operation 11Chapter 3. SVA Path OperationThis chapter describes SVA Path commands and configuration options.There are three bas

12 SVA Path User’s GuideCommand options that take arguments (shown in braces after the command) require an argument and should not be run without one.

Chapter 3. SVA Path Operation 13-L <parameter>show current device configuration according to condition(s) defined by setsp command option par

14 SVA Path User’s GuideThe spmon CommandThe spmon command is primarily associated with load monitoring and balancing of SVA Path functional devices (

Chapter 3. SVA Path Operation 15equation must be less than the percentage value of balance-threshold to be considered balanced.• reassignment-thres

16 SVA Path User’s GuideHow to Verify LoadBalancingIn Figure 3-4, “Example setsp -a Output in Determining Load Balancing”, there are four SVA Path dev

Chapter 3. SVA Path Operation 17In our example, the following command will show that each device in Figure 3-4, “Example setsp -a Output in Determi

18 SVA Path User’s Guideseconds (with an "s" suffix) if it is less than 300 seconds. For example, 18.1s = 28.1 secondshours:minutes:seconds

Chapter 3. SVA Path Operation 19Figure 3-7 Example spmon show Output, Next IntervalAdding FDevs to anExisting LunAfter adding new FDevs to an exist

Table of Contents iiiTable of Contents Who Should Read This Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

20 SVA Path User’s GuideThe sppath CommandThe sppath command is run automatically at boot after SVA Path is installed. sppath’s main function is to cr

Chapter 3. SVA Path Operation 21Table 3-2, “sppath Command Options” gives a synopsis of sppath options. They are explained in greater detail below.

22 SVA Path User’s GuideThe -d option displays inquiry data in raw format and is generally used only for debugging. Ignoring andReclaiming Deviceswith

Chapter 3. SVA Path Operation 23Understanding the setsp -a ScreenUse the setsp -a command to display the default path configurations. Figure 3-1 Sa

24 SVA Path User’s Guide• Status shows the current state of the path. Good paths are functioning normally. Bad paths have failed.•Primary shows which

Chapter 3. SVA Path Operation 25default value is 3000 ms. This value can not be set above 100,000 ms (100s).•FailBack indicates whether failback is

26 SVA Path User’s GuideAssigning a NewPrimary PathThe syntax for changing an SVA LUN’s primary data path issetsp -l<x> -p<n> where <x&

Chapter 3. SVA Path Operation 27All devices may be included, as they present no conflicts. However, in a multiple-host environment, where all spds

28 SVA Path User’s Guidewhere <x> is the numerical element of the spd number and <n> is the interval between the retries specified by the

Chapter 3. SVA Path Operation 295. Start the new SVA Path device with:# setsp -S -l <new_spd_number>6. Unexclude the new device:# setsp -e0 -

iv SVA Path User’s GuideChapter 3. SVA Path Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

30 SVA Path User’s Guide

Chapter 4. SVA Path Installation 31Chapter 4. SVA Path InstallationThis chapter describes how to install SVA Path for use with SVA 9500. Installati

32 SVA Path User’s Guide3. Before installing SVA Path, it is imperative that the host is able to see and access all storage devices through all availa

Chapter 4. SVA Path Installation 33complete all active processes, wait 3 minutes before pressing the “Finish” button on the last panel of the insta

34 SVA Path User’s GuideNote: If SVA Path is installed after SVAA, SVA Path will claim the SVAA device. Run the following commands, which will cause

Chapter 4. SVA Path Installation 35Installed FilesDuring installation, the files listed in Table 4-1, “Installed SVA Path Files” are placed in your

36 SVA Path User’s Guide

Chapter 4. SVA Path Installation 37SVA Path Device Naming on HP-UXDisk device filenames in HP-UX 10.x and higher have names in the following format

38 SVA Path User’s GuideSVA Path installations, SVA Path creates a single additional device filename for applications to access the device and manages

Chapter 4. SVA Path Installation 39Path is installed, be accessed through the SVA Path device file c81t4d0 (Figure 4-1). Figure 4-1 SVA Path Dev

Table of Contents vChapter 5. Diagnosing Errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

40 SVA Path User’s GuideIf there are more than one set of redundant paths, there could be more than one device with a given target and LUN number. For

Chapter 4. SVA Path Installation 41This section shows how to create a new volume group and add a disk drive to it, using example screens from an HP

42 SVA Path User’s GuidePreparing theVolume GroupDevice files for each volume group on an HP 9000 system reside in directories with names /dev/vg*. Th

Chapter 4. SVA Path Installation 43• a minor number of the form 0xNN0000, where NN is the two-digit hexadecimal representation of the volume group

44 SVA Path User’s GuideTo verify the creation and view the volume group characteristics, use the vgdisplay command:In the output of vgdisplay, the To

Chapter 4. SVA Path Installation 45multiple of the physical extent size that is 4 MB by default. In the example below, a volume group of 4092 MB is

46 SVA Path User’s GuideThe Free PE field in the vgdisplay output shows that the number of free physical extents in the volume group has decreased:You

Chapter 4. SVA Path Installation 47first export the volume group and them import it using the new special device filenames that SVA Path assigns.In

48 SVA Path User’s Guide3. Unmount all of the logical volumes in the volume group and deactivate the volume group by entering the following command:#

Chapter 4. SVA Path Installation 498. Select the SVA Path devices that correspond to the original device filenames of the physical volumes of the v

vi SVA Path User’s Guide

50 SVA Path User’s Guide

Chapter 5. Diagnosing Errors 51Chapter 5. Diagnosing ErrorsComparing setsp -a with System EventsSVA Path necessarily interfaces with system compone

52Cable Failure ErrorsFigure 5-2, “Messages Generated When a Cable Is Pulled” illustrates error messages that will occur in the file /var/adm/syslog/s

Chapter 5. Diagnosing Errors 53Errors for other spd devices, representing the same physical I/O path that was interrupted by the pulled cable, will

54shows that every device’s path 0 (those corresponding to device filenames beginning c7) have a Status designation of Bad.Figure 5-6 setsp -a Output

Chapter 5. Diagnosing Errors 55Manual Name:Please check or fill in the items; adding explanations/comments in the space provided.Which of the follo

56TO COMPLY WITH POSTAL REGULATIONS, FOLD EXACTLY ON DOTTED LINES AND TAPE (DO NOT STAPLE)DO NOT STAPLEFOLD HERE AND TAPEFOLD HERE AND TAPENO POSTAGEN

Printed in U.S.A

Preface viiPreface This guide describes how to use the SVA Path Intelligent Data Path Management software. SVA Path provides improved performance

viii SVA Path User’s Guide• Online (for viewing and printing), at the StorageTek Customer Resource Center (CRC) website at: www.support.storagetek.com

Preface ixSVA HardwarePublicationsShared Virtual Array hardware publications are available from the following sources:• On the SVA Hardware Public