sdd 1.8--3.4 user guide english version(1)

IBM System Storage

Multipath Subsystem Device DriverUser's Guide

GC52-1309-05

IBM License Agreement for Machine CodeThis guide might contain references to machine code, which includes Licensed Internal Code. Licensed Internal Code is licensedto you under the terms of the IBM License Agreement for Machine Code. Carefully read the agreement. By using this product,you agree to abide by the terms of this agreement and applicable copyright laws. See IBM license agreement for machine codeon page 467.

ii Multipath Subsystem Device Driver User's Guide

NoteBefore using this information and the product it supports, read the information in Notices on page 465.

This edition applies to the following versions of IBM Multipath Subsystem Device Driver and to all subsequentreleases and modifications until otherwise indicated in new editions:Subsystem Device Driver Version 1 Release 8 Modification 0 Level x for HP-UXSubsystem Device Driver Version 1 Release 7 Modification 2 Level x for AIXSubsystem Device Driver Version 1 Release 6 Modification 5 Level x for SolarisSubsystem Device Driver Version 1 Release 6 Modification 4 Level x for WindowsSubsystem Device Driver Version 1 Release 6 Modification 3 Level x for LinuxSubsystem Device Driver Version 1 Release 6 Modification 0 Level x for NetwareSubsystem Device Driver Device Specific Module Version 2 Release 4 Modification x Level xSubsystem Device Driver Device Specific Module Version 2 Release 4 Modification 3 Level 4 for WindowsSubsystem Device Driver Path Control Module Version 3 Release 0 Modification x Level xSubsystem Device Driver Path Control Module Version 2 Release 6 Modification 4 Level 0

This edition replaces GC52-1309-04.

Copyright IBM Corporation 1999, 2013.US Government Users Restricted Rights Use, duplication or disclosure restricted by GSA ADP Schedule Contractwith IBM Corp.

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iv Multipath Subsystem Device Driver User's Guide

ContentsFigures . . . . . . . . . . . . . . xv

Tables . . . . . . . . . . . . . . xvii

About this guide . . . . . . . . . . xixWho should use this guide . . . . . . . . . xixSummary of changes . . . . . . . . . . . xix

Updated information . . . . . . . . . . xxCommand syntax conventions . . . . . . . . xx

Highlighting conventions . . . . . . . . . xxSpecial characters conventions . . . . . . . xx

Related information . . . . . . . . . . . xxThe ESS library . . . . . . . . . . . . xxiThe DS8000 library . . . . . . . . . . xxiiiThe DS6000 library . . . . . . . . . . xxiiiThe DS5000 and DS Storage Manager library xxiiiThe DS4000 library . . . . . . . . . . xxivThe SAN Volume Controller library . . . . . xxvThe Tivoli Storage Productivity Center andTivoli Storage Productivity Center forReplication libraries . . . . . . . . . . xxvOrdering IBM publications . . . . . . . xxvi

IBM Publications Center . . . . . . . xxviHow to send your comments . . . . . . . . xxvi

Chapter 1. Overview of the SDD . . . . 1The SDD architecture . . . . . . . . . . . 2Enhanced data availability . . . . . . . . . . 4Dynamic I/O load balancing . . . . . . . . . 6Automatic path-failover protection . . . . . . . 6Concurrent download of licensed machine code fordisk storage systems . . . . . . . . . . . . 7Concurrent download of licensed machine code forvirtualization products . . . . . . . . . . . 7Concurrent download of licensed machine code forDS3950, DS4000 and DS5000 . . . . . . . . . 8Concurrent download of licensed machine code forIBM BladeCenter S SAS RAID Controller Module(RSSM) . . . . . . . . . . . . . . . . 8Active/Passive dual array controller path-selectionalgorithm for DS3950, DS4000 and DS5000 products . 8Preferred node path-selection algorithm for thevirtualization products . . . . . . . . . . . 9Open HyperSwap Replication . . . . . . . . 9

Chapter 2. Using the SDD on an AIXhost system . . . . . . . . . . . . 11Supported SDD features . . . . . . . . . . 11Verifying the hardware and software requirements 12

Hardware . . . . . . . . . . . . . . 12Software . . . . . . . . . . . . . . 12Unsupported environments . . . . . . . . 13Host system requirements . . . . . . . . 13

Disk storage systems requirements . . . . 14

Virtualization products requirements . . . . 14SCSI requirements for ESS . . . . . . . 14Fibre requirements . . . . . . . . . . 14

Preparing for the SDD installation . . . . . . . 15Configuring the disk storage system . . . . . 15Configuring the virtualization products . . . . 16Installing the AIX fibre-channel device drivers. . 16Uninstalling the AIX fibre-channel device drivers 17

Using the smitty deinstall command . . . . 17Using the installp command . . . . . . . 17

Installing and upgrading the AIX SDD hostattachment . . . . . . . . . . . . . 18Configuring fibre-channel-attached devices . . . 18Removing fibre-channel-attached devices . . . 18Verifying the adapter firmware level . . . . . 19Determining if the sddServer for Expert isinstalled . . . . . . . . . . . . . . 19Understanding SDD support for IBM System pwith static LPARs configured . . . . . . . 20Determining the installation package . . . . . 20

Installation packages for 32-bit and 64-bitapplications on AIX 4.3.3 (or later) hostsystems. . . . . . . . . . . . . . 20Switching between 32-bit and 64-bit modes onAIX 5.1.0, AIX 5.2.0, and AIX 5.3.0 hostsystems. . . . . . . . . . . . . . 21Installation of major files on your AIX hostsystem . . . . . . . . . . . . . . 21

Determining the installation type . . . . . . 22Installing and upgrading the SDD . . . . . . . 23

Installing the SDD . . . . . . . . . . . 23Installing the SDD from CD-ROM . . . . . 23Installing SDD from downloaded code . . . 24

Upgrading the SDD . . . . . . . . . . 24Upgrading the SDD packages automaticallywithout system restart . . . . . . . . . 24Upgrading SDD manually . . . . . . . 28Updating SDD packages by applying aprogram temporary fix . . . . . . . . 29Upgrading AIX OS or host attachment andSDD packages . . . . . . . . . . . 32Case 1: In stand-alone host or with theHACMP services stopped . . . . . . . 32Case 2: In HACMP node-by-node migrationwith nonconcurrent resource group . . . . 34

Verifying the currently installed version of SDDfor SDD 1.3.3.11 (or earlier) . . . . . . . . 35Verifying the currently installed version of SDDfor SDD 1.4.0.0 (or later) . . . . . . . . . 37

Preparing to configure SDD . . . . . . . . . 38Maximum number of LUNs . . . . . . . . 38

ODM attributes for controlling the maximumnumber of LUNs in SDD version 1.6.0.7 orlater on AIX 5.2 and later . . . . . . . . 40

Copyright IBM Corp. 1999, 2013 v

Preparing your system to configure more than600 supported storage devices or to handle alarge amount of I/O after queue depth isdisabled . . . . . . . . . . . . . 40

Controlling I/O flow to SDD devices with theSDD qdepth_enable attribute . . . . . . . 43Controlling reserve policy of SDD devices withthe SDD reserve_policy attribute . . . . . . 44

Configuring SDD . . . . . . . . . . . . 45Unconfiguring SDD . . . . . . . . . . 45Verifying the SDD configuration . . . . . . 46Dynamically adding paths to SDD vpath devices 47Dynamically removing or replacing PCI adaptersor paths . . . . . . . . . . . . . . 47

Dynamically removing a PCI adapter fromSDD configuration . . . . . . . . . . 47Dynamically replacing a PCI adapter in anSDD configuration . . . . . . . . . . 48Dynamically removing a path of an SDDvpath device . . . . . . . . . . . . 49

Removing SDD from an AIX host system . . . . 50Special considerations when you uninstall SDDin the NIM environment . . . . . . . . . 51

Removing SDD Host Attachment from an AIX hostsystem . . . . . . . . . . . . . . . . 51SAN boot support . . . . . . . . . . . . 52

Manual exclusion of devices from the SDDconfiguration . . . . . . . . . . . . . 52Replacing manually excluded devices in the SDDconfiguration . . . . . . . . . . . . . 52SAN boot installation procedures . . . . . . 53

SAN boot installation procedure for AIX 5.1 53SAN boot installation procedure for AIX 5.2,AIX 5.3, and AIX 6.1 . . . . . . . . . 53

Understanding SDD support for High AvailabilityCluster Multiprocessing . . . . . . . . . . 54

SDD persistent reserve attributes . . . . . . 56Preparation for importing volume groups underHACMP . . . . . . . . . . . . . . 57HACMP RAID concurrent-mode volume groupsand enhanced concurrent-capable volume groups. 58

Creating HACMP RAID concurrent-modevolume groups . . . . . . . . . . . 59Importing HACMP RAID concurrent-modevolume groups . . . . . . . . . . . 59Removing HACMP RAID concurrent-modevolume groups . . . . . . . . . . . 62Extending HACMP RAID concurrent-modevolume groups . . . . . . . . . . . 62Reducing HACMP RAID concurrent-modevolume groups . . . . . . . . . . . 63Exporting HACMP RAID concurrent-modevolume groups . . . . . . . . . . . 64Enhanced concurrent-capable volume groups 64Recovering paths that are lost during HACMPnode fallover that is caused when a systemlocks up . . . . . . . . . . . . . 66Supporting enhanced concurrent mode in anHACMP environment . . . . . . . . . 67

SDD server daemon . . . . . . . . . . . 67Verifying if the SDD server has started . . . . 68

Starting the SDD server manually . . . . . . 68Changing to a different port number for the SDDserver . . . . . . . . . . . . . . . 68Stopping the SDD server . . . . . . . . . 68Replacing the SDD server with a stand-aloneversion . . . . . . . . . . . . . . . 69PTFs for APARs on AIX with Fibre Channel andthe SDD server . . . . . . . . . . . . 69

Dynamically changing the SDD path-selection policyalgorithm . . . . . . . . . . . . . . . 70

datapath set device policy command . . . . . 70Dynamically opening an invalid or close_dead path 71Fibre-channel dynamic device tracking for AIX 5.20TL1 (and later) . . . . . . . . . . . . . 71Understanding SDD 1.3.2.9 (or later) support forsingle-path configuration for supported storagedevices . . . . . . . . . . . . . . . . 72Understanding the persistent reserve issue whenmigrating from SDD to non-SDD volume groupsafter a system reboot . . . . . . . . . . . 72Managing secondary-system paging space . . . . 73

Listing paging spaces . . . . . . . . . . 73Adding a paging space . . . . . . . . . 73Removing a paging space . . . . . . . . 73

Verifying load-balancing and failover protection . . 73Displaying the supported storage device SDDvpath device configuration . . . . . . . . 74Configuring volume groups for failoverprotection . . . . . . . . . . . . . . 75

Losing failover protection . . . . . . . . . 76Losing a device path . . . . . . . . . . 77Creating a volume group from single-path SDDvpath devices. . . . . . . . . . . . . 77A side effect of running the disk change method 77Manually deleting devices and running theconfiguration manager (cfgmgr) . . . . . . 79

Using LVM with SDD . . . . . . . . . . . 79Importing volume groups with SDD . . . . . 79Exporting a volume group with SDD . . . . . 80Recovering from mixed volume groups . . . . 81Extending an existing SDD volume group . . . 81Backing up all files belonging to an SDD volumegroup . . . . . . . . . . . . . . . 81Restoring all files belonging to an SDD volumegroup . . . . . . . . . . . . . . . 82

SDD-specific SMIT panels . . . . . . . . . 82Accessing the Display Data Path DeviceConfiguration SMIT panel . . . . . . . . 83Accessing the Display Data Path Device StatusSMIT panel . . . . . . . . . . . . . 84Accessing the Display Data Path Device AdapterStatus SMIT panel . . . . . . . . . . . 84Accessing the Define and Configure All DataPath Devices SMIT panel . . . . . . . . . 85Accessing the Add Paths to Available Data PathDevices SMIT panel . . . . . . . . . . 85Accessing the Configure a Defined Data PathDevice SMIT panel . . . . . . . . . . . 85Accessing the Remove a Data Path Device SMITpanel . . . . . . . . . . . . . . . 85

vi Multipath Subsystem Device Driver User's Guide

Accessing the Add a Volume Group with DataPath Devices SMIT panel . . . . . . . . . 85Accessing the Add a Data Path Volume to aVolume Group SMIT panel . . . . . . . . 86Accessing the Remove a Physical Volume from aVolume Group SMIT panel . . . . . . . . 86Accessing the Backup a Volume Group with DataPath Devices SMIT panel . . . . . . . . . 86Accessing the Remake a Volume Group withData Path Devices SMIT panel . . . . . . . 87

SDD utility programs . . . . . . . . . . . 87addpaths . . . . . . . . . . . . . . 87hd2vp and vp2hd . . . . . . . . . . . 88dpovgfix . . . . . . . . . . . . . . 88lsvpcfg . . . . . . . . . . . . . . . 88mkvg4vp . . . . . . . . . . . . . . 89extendvg4vp . . . . . . . . . . . . . 90excludesddcfg . . . . . . . . . . . . 90lquerypr . . . . . . . . . . . . . . 91sddgetdata . . . . . . . . . . . . . 91

Persistent reserve command tool . . . . . . . 91Using supported storage devices directly . . . . 93Using supported storage devices through AIX LVM 94Migrating a non-SDD volume group to a supportedstorage device SDD multipath volume group inconcurrent mode . . . . . . . . . . . . 94

Detailed instructions for migrating a non-SDDvolume group to a supported storage device SDDmultipath volume group in concurrent mode . . 96

Using the trace function . . . . . . . . . . 98

Chapter 3. Using SDDPCM on an AIXhost system . . . . . . . . . . . . 99Supported SDDPCM features . . . . . . . . 101Unsupported SDDPCM features . . . . . . . 102Verifying the hardware and software requirements 102

Hardware . . . . . . . . . . . . . 102Software . . . . . . . . . . . . . . 103Unsupported environments. . . . . . . . 103Host system requirements . . . . . . . . 103

Supported storage device requirements . . . 103Fibre requirements . . . . . . . . . 104

Preparing for SDDPCM installation . . . . . . 104Preparing for SDDPCM installation forsupported storage devices . . . . . . . . 105

Determining the correct installation package 106Determining if the SDD package is installed 106Determining if the ibm2105.rte package isinstalled . . . . . . . . . . . . . 106Determining if the devices.fcp.disk.ibm.rtepackage is installed . . . . . . . . . 106Installing the AIX fibre-channel devicedrivers . . . . . . . . . . . . . 106Verifying and upgrading the fibre-channeladapter firmware level . . . . . . . . 108Verifying and Upgrading SAS controllerfirmware . . . . . . . . . . . . . 109

Installing and upgrading the AIX SDDPCM hostattachment . . . . . . . . . . . . . . 109Installing and upgrading SDDPCM . . . . . . 110

Installing SDDPCM from CD-ROM . . . . . 110

Creating and mounting the CD-ROMfilesystem. . . . . . . . . . . . . 111Using the System Management Interface Toolfacility to install SDDPCM . . . . . . . 112Unmounting the CD-ROM File System . . . 113

Installing SDDPCM from downloaded code . . 113Installing SDDPCM with the AIX OS from anAIX NIM SPOT server to the client SAN bootdisk or the internal boot disk . . . . . . . 113Updating SDDPCM . . . . . . . . . . 114

Updating SDDPCM packages by installing anewer base package or a program temporaryfix . . . . . . . . . . . . . . . 114Committing or rejecting a programtemporary fix update . . . . . . . . . 116Verifying the currently installed version ofSDDPCM. . . . . . . . . . . . . 116Maximum number of devices that SDDPCMsupports . . . . . . . . . . . . . 116

Migrating SDDPCM . . . . . . . . . . 117Migrating the supported storage SAN bootdevice or nonboot volume group from AIXdefault PCM to SDDPCM . . . . . . . 117Migrating from SDDPCM to the AIX defaultPCM or to SDD . . . . . . . . . . 118Migrating from SDD with SAN boot devices(on supported storage hdisks) to SDDPCMwith multipath SAN boot devices . . . . 119Migrating SDDPCM during an AIX OSupgrade with multipath SAN boot devices(on supported storage hdisks) . . . . . . 119

Configuring and unconfiguring supported storageMPIO-capable devices . . . . . . . . . . 119

Configuring supported storage MPIO-capabledevices . . . . . . . . . . . . . . 119Verifying the SDDPCM configuration . . . . 120Dynamically adding and removing paths oradapters . . . . . . . . . . . . . . 120Unconfiguring supported storage MPIO-capabledevices . . . . . . . . . . . . . . 122Switching DS4000, DS5000, or DS3950 storagedevice configurations . . . . . . . . . . 122

Removing SDDPCM from an AIX host system . . 123SDDPCM support for HACMP with EnhancedConcurrent Mode volume groups . . . . . . 124MPIO reserve policies . . . . . . . . . . 125

No Reserve reservation policy . . . . . . . 125Exclusive Host Access single-path reservationpolicy . . . . . . . . . . . . . . . 125Persistent Reserve Exclusive Host Accessreservation policy . . . . . . . . . . . 125Persistent Reserve Shared Host Accessreservation policy . . . . . . . . . . . 125

SDDPCM active/passive storage device controllerhealth-check feature . . . . . . . . . . . 126SDDPCM ODM attribute settings. . . . . . . 126

SDDPCM ODM attribute default settings . . . 127Changing device reserve policies . . . . . . 127Changing the path selection algorithm . . . . 127Using the load balancing port algorithm . . . 128Changing SDDPCM path healthcheck mode . . 129

Contents vii

Changing SDDPCM path healthcheck timeinterval . . . . . . . . . . . . . . 130Changing the Open HyperSwap quiesce expiretime . . . . . . . . . . . . . . . 131

Supported AIX fibre-channel device driver features 131Fast I/O failure of fibre-channel devices . . . 131Fibre channel dynamic device tracking . . . . 132Changing SDDPCM controller healthcheckdelay_time . . . . . . . . . . . . . 133Changing SDDPCM controller healthcheckinterval time. . . . . . . . . . . . . 133

Multipath SAN boot support . . . . . . . . 134Configuring supported storage system MPIOdevices as the SAN boot device . . . . . . 134

Support system dump device with the supportedstorage system MPIO device . . . . . . . . 135Dynamically enabling and disabling paths oradapters . . . . . . . . . . . . . . . 136

Dynamically enabling or disabling a path . . . 136Dynamically enabling or disabling an adapter 137

Using the SDDPCM trace function . . . . . . 137SDDPCM server daemon . . . . . . . . . 138

Verifying if the SDDPCM server has started . . 138Starting the SDDPCM server manually . . . . 138Stopping the SDDPCM server . . . . . . . 139

AE daemon . . . . . . . . . . . . . . 139Verifying if the AE server has started . . . . 139Starting the AE server manually . . . . . . 140Stopping the AE server manually. . . . . . 140

SDDPCM utility programs . . . . . . . . . 140Persistent reserve command tools . . . . . 140

pcmquerypr . . . . . . . . . . . . 140pcmgenprkey . . . . . . . . . . . 143sddpcm_get_config . . . . . . . . . 144

Using SDDPCM pcmpath commands . . . . 144pcmpath clear device count. . . . . . . 147pcmpath disable ports . . . . . . . . 148pcmpath enable ports . . . . . . . . 150pcmpath open device path . . . . . . . 152pcmpath query adapter . . . . . . . . 154pcmpath query adaptstats . . . . . . . 156pcmpath query device . . . . . . . . 158pcmpath query devstats . . . . . . . . 164pcmpath query essmap . . . . . . . . 166pcmpath query port . . . . . . . . . 167pcmpath query portmap. . . . . . . . 169pcmpath query portstats. . . . . . . . 170pcmpath query session . . . . . . . . 172pcmpath query version . . . . . . . . 173pcmpath query wwpn . . . . . . . . 174pcmpath set adapter . . . . . . . . . 175pcmpath set device algorithm . . . . . . 177pcmpath set device hc_interval . . . . . 178pcmpath set device hc_mode . . . . . . 179pcmpath set device cntlhc_interval . . . . 180pcmpath set device cntlhc_delay . . . . . 181pcmpath set device path. . . . . . . . 182pcmpath chgprefercntl device . . . . . . 183Summary of command syntax . . . . . . 185

Chapter 4. Using the SDD on anHP-UX host system . . . . . . . . . 187Verifying the hardware and software requirements 187

Hardware . . . . . . . . . . . . . 187Software . . . . . . . . . . . . . . 187

SDD-supported HP-UX kernel levels . . . 187Unsupported environments. . . . . . . . 188Understanding how SDD works on an HP-UXhost system . . . . . . . . . . . . . 188

Preparing for the SDD installation . . . . . . 188Configuring the disk storage system. . . . . 188Configuring the virtualization products . . . 188Configuring DS4000 and DS5000 family disksystems . . . . . . . . . . . . . . 188Bypassing the boot disk check . . . . . . . 189Planning for installation . . . . . . . . . 189Determining if the SDD 1.3.1.5 (or later) serverfor Expert is installed. . . . . . . . . . 190

Installing SDD . . . . . . . . . . . . . 191Installing SDD from CD-ROM. . . . . . . 191Installing SDD from downloaded code . . . . 192Upgrading the SDD . . . . . . . . . . 193

Upgrading from SDD 1.6.0.x to SDD 1.6.1.0or later with concurrent access . . . . . 193Upgrading from SDD 1.5.0.4 to SDD 1.6.1.0or later with nonconcurrent access. . . . . 194Upgrading SDD 1.3.0.2 or earlier to SDD1.5.0.4 or later . . . . . . . . . . . 194

Installing an additional package for DS4000 andDS5000 support . . . . . . . . . . . . 195Configuring the SDD . . . . . . . . . . . 195

Maximum number of LUNs . . . . . . . 195Changing an SDD hardware configuration . . 195Converting a volume group . . . . . . . 196Dynamic reconfiguration . . . . . . . . 196Dynamically changing the SDD path-selectionpolicy algorithm . . . . . . . . . . . 196

datapath set device policy command . . . 197Preferred node path-selection algorithm for thevirtualization products . . . . . . . . . 197SDD datapath query adapter command changesfor SDD 1.4.0.0 (or later). . . . . . . . . 198SDD datapath query device command changesfor SDD 1.4.0.0 (or later). . . . . . . . . 199

Postinstallation . . . . . . . . . . . . . 200Uninstalling SDD . . . . . . . . . . . . 202SDD server daemon . . . . . . . . . . . 203

Verifying if the SDD server has started . . . . 203Starting the SDD server manually . . . . . 204Changing to a different port number for theSDD server . . . . . . . . . . . . . 204Stopping the SDD server . . . . . . . . 204

How to import and export volume groups . . . 204Exporting volume groups . . . . . . . . 205Moving the map file . . . . . . . . . . 205Creating the volume group device directory . . 205Creating the group special file . . . . . . . 206Importing volume groups . . . . . . . . 206Exporting or importing MC Service Guardvolume groups . . . . . . . . . . . . 206

Using applications with SDD . . . . . . . . 208

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Standard UNIX applications . . . . . . . 208Creating new logical volumes . . . . . . 209Removing logical volumes . . . . . . . 211Re-creating the existing logical volumes . . 211

Installing SDD on a NFS file server . . . . . 213Setting up NFS for the first time . . . . . 213Installing SDD on a system that already hasthe NFS file server . . . . . . . . . 214

Chapter 5. Using SDD on a Linux hostsystem . . . . . . . . . . . . . . 215Verifying hardware and software requirements . . 215

Hardware . . . . . . . . . . . . . 215Software . . . . . . . . . . . . . . 215Unsupported environments. . . . . . . . 216

Preparing for SDD installation. . . . . . . . 216Configuring disk storage systems. . . . . . 216Configuring virtualization products . . . . . 216Configuring fibre-channel adapters on diskstorage systems. . . . . . . . . . . . 216Configuring fibre-channel adapters onvirtualization products . . . . . . . . . 217Disabling automatic Linux system updates . . 217

Installing SDD . . . . . . . . . . . . . 217Installing SDD from CD-ROM. . . . . . . 217Installing SDD from downloaded code . . . . 218Upgrading SDD . . . . . . . . . . . 218Verifying the SDD installation . . . . . . . 219

Configuring SDD . . . . . . . . . . . . 220Configurating and verifying an SDD . . . . 221

SDD configuration. . . . . . . . . . 221Verifying SDD configuration . . . . . . 222Automatic SCSI disk device exclusion duringSDD configuration. . . . . . . . . . 225

Reconfiguring using SDD userspace commands 225cfgvpath . . . . . . . . . . . . . 225rmvpath . . . . . . . . . . . . . 226lsvpcfg . . . . . . . . . . . . . 226addpaths . . . . . . . . . . . . . 226

Configuring SDD at system startup . . . . . 226Maintaining SDD vpath device configurationpersistence . . . . . . . . . . . . . 227Dynamically changing the SDD path-selectionpolicy algorithm . . . . . . . . . . . 228

datapath set device policy command . . . 229Using dynamic reconfiguration . . . . . . 229

Uninstalling SDD . . . . . . . . . . . . 230Mounting SDD devices with automount . . . . 230

Setting up automount . . . . . . . . . 230Configuring automount . . . . . . . . . 231Sample mount output . . . . . . . . . 232

Using Linux Logical Volume Manager with SDD 233Using LVM on SUSE . . . . . . . . . . 234Using LVM on Red Hat . . . . . . . . . 235LVM 2 general configuration information . . . 236

Booting Linux over the SAN with SDD. . . . . 237SAN Boot instructions for RHEL 3 with IBMSDD (x86) . . . . . . . . . . . . . 237

Prerequisite steps . . . . . . . . . . 237Verifying the SAN boot configuration . . . 239Upgrading the SDD . . . . . . . . . 244

SAN Boot instructions for RHEL 3 with IBMSDD (ppc) . . . . . . . . . . . . . 244

Prerequisite steps . . . . . . . . . . 244SAN boot configuration . . . . . . . . 246SDD upgrade procedure. . . . . . . . 252

SAN Boot Instructions for SLES 8 with IBMSDD (x86) . . . . . . . . . . . . . 253


SAN Boot Instructions for SLES 9 with IBMSDD (x86) . . . . . . . . . . . . . 262


SAN Boot instructions for SLES 9 with IBM(ppc) . . . . . . . . . . . . . . . 268

Prerequisite steps . . . . . . . . . . 268SAN boot configuration . . . . . . . . 270Upgrading the SDD . . . . . . . . . 275

SAN Boot Instructions for SLES 9 with IBMSDD (x86) and LVM 2 . . . . . . . . . 276

Prerequisite steps . . . . . . . . . . 276SAN boot configuration . . . . . . . . 277

SAN boot instructions for RHEL 4 with IBMSDD (x86) . . . . . . . . . . . . . 283


SAN Boot instructions for RHEL 4 with IBMSDD (ppc) . . . . . . . . . . . . . 289


SAN boot instructions for RHEL 4 with IBMSDD (x86) and LVM 2 . . . . . . . . . 295

Prerequisite steps . . . . . . . . . . 295SAN boot configuration . . . . . . . . 297

Using lilo with SDD (remote boot) on x86 . . . 302Manually specifying disk geometry of theboot device . . . . . . . . . . . . 303

SDD server daemon . . . . . . . . . . . 305Verifying if the SDD server has started . . . . 305Starting the SDD server manually . . . . . 305Changing to a different port number for theSDD server . . . . . . . . . . . . . 306Stopping the SDD server . . . . . . . . 306Collecting trace information . . . . . . . 306

Understanding SDD support for single-pathconfiguration . . . . . . . . . . . . . 306Partitioning SDD vpath devices . . . . . . . 307Using standard UNIX applications . . . . . . 307Managing common issues . . . . . . . . . 308

Chapter 6. Using the SDD on aNetWare host system . . . . . . . . 311Verifying the hardware and software requirements 311

Hardware requirements . . . . . . . . . 311Software requirements . . . . . . . . . 311Supported environments . . . . . . . . 312Unsupported environments. . . . . . . . 312

Contents ix

Disk storage system requirements . . . . . 312SCSI requirements . . . . . . . . . . . 312Fibre-channel requirements . . . . . . . . 313

Preparing for SDD installation. . . . . . . . 313Configuring the disk storage system. . . . . 313Configuring fibre-channel adapters . . . . . 313Configuring SCSI adapters . . . . . . . . 314Using a NetWare Compaq Server. . . . . . 314

Installing SDD . . . . . . . . . . . . . 315Installing SDD from CD-ROM. . . . . . . 315Installing SDD from downloaded code . . . . 315

Configuring SDD . . . . . . . . . . . . 315Maximum number of LUNs . . . . . . . 316

Displaying the current version of the SDD. . . . 316Features . . . . . . . . . . . . . . . 316

Automatic path detection, failover and selection 316Manual operations using the datapathcommands . . . . . . . . . . . . . 317Understanding SDD error recovery algorithms 318

Single-path mode . . . . . . . . . . 318Multiple-path mode . . . . . . . . . 318

Dynamic load balancing . . . . . . . . . 318Disk storage system logical unit detection . . . 318Error reporting and logging . . . . . . . 318SDD in NetWare-layered architecture . . . . 319

Display a single device for a multipathdevice . . . . . . . . . . . . . . 319

Removing the SDD . . . . . . . . . . . 319Cluster setup for Novell NetWare 5.1 . . . . . 320Cluster setup for Novell NetWare 6.0 . . . . . 320

Examples of commands output on the ConsoleWindow . . . . . . . . . . . . . . 320

Chapter 7. Using the SDD on a Solarishost system . . . . . . . . . . . . 325Verifying the hardware and software requirements 325

Hardware . . . . . . . . . . . . . 325Software . . . . . . . . . . . . . . 325Supported environments . . . . . . . . 326Unsupported environments. . . . . . . . 326Understanding how SDD works on a Solarishost system . . . . . . . . . . . . . 326

Preparing for SDD installation. . . . . . . . 326Configuring disk storage systems. . . . . . 326Configuring virtualization products . . . . . 326Determining if the SDD server for Expert isinstalled . . . . . . . . . . . . . . 326Planning for installation . . . . . . . . . 327

Installing SDD . . . . . . . . . . . . . 329Installing SDD from CD-ROM. . . . . . . 329Installing SDD from downloaded code . . . . 331

Installing SDD in Jumpstart Environment . . 331Postinstallation . . . . . . . . . . . . 331Verifying the SDD installation . . . . . . . 334Upgrading the SDD . . . . . . . . . . 334

Configuring the SDD . . . . . . . . . . . 335Changing an SDD hardware configuration . . 335

Option 1: Reconfigure the system andreconfigure the SDD . . . . . . . . . 335Option 2: Dynamic reconfiguration . . . . 335

Solaris 10 ZFS support . . . . . . . . . 337

Solaris 10 Zone support . . . . . . . . . 337SDD installation in a server with nonglobalzones . . . . . . . . . . . . . . 337Access SDD vpath devices in nonglobalzones . . . . . . . . . . . . . . 337

Dynamically changing the SDD path-selectionpolicy algorithm . . . . . . . . . . . 338

datapath set device policy command . . . 339Excluding LUNs from being configured by SDD 339

Determining the LUN identifier of a LUN 339Uninstalling the SDD. . . . . . . . . . . 340Understanding SDD support for single-pathconfiguration for disk storage system . . . . . 341SDD server daemon . . . . . . . . . . . 341

Verifying if the SDD server has started . . . . 341Starting the SDD server manually . . . . . 341Changing to a different port number for theSDD server . . . . . . . . . . . . . 341Changing the retry count value when probingSDD server inquiries . . . . . . . . . . 342Stopping the SDD server . . . . . . . . 342

Using applications with SDD . . . . . . . . 342Standard UNIX applications . . . . . . . 343Installing the SDD on a NFS file server . . . . 343

Setting up NFS for the first time . . . . . 343Installing SDD on a system that already hasthe Network File System file server . . . . 343

Veritas Volume Manager. . . . . . . . . 344Oracle . . . . . . . . . . . . . . . 345

Installing an Oracle database for the firsttime . . . . . . . . . . . . . . 345Installing an SDD on a system that alreadyhas Oracle in place . . . . . . . . . 346

Solaris Volume Manager (formerly SolsticeDiskSuite) . . . . . . . . . . . . . 348

Installing Solaris Volume Manager for thefirst time . . . . . . . . . . . . . 349Installing SDD on a system that already hasSolstice DiskSuite in place . . . . . . . 349Setting up transactional volume for UFSlogging on a new system . . . . . . . 350Installing vpath on a system that already hastransactional volume for UFS logging inplace . . . . . . . . . . . . . . 351

Chapter 8. Using the SDD on aWindows NT host system . . . . . . 353Verifying the hardware and software requirements 353

Hardware . . . . . . . . . . . . . 353Software . . . . . . . . . . . . . . 353Unsupported environments. . . . . . . . 353ESS requirements . . . . . . . . . . . 354Host system requirements . . . . . . . . 354

SCSI requirements . . . . . . . . . . 354Fibre-channel requirements . . . . . . . 354

Preparing for SDD installation. . . . . . . . 355Configuring the ESS . . . . . . . . . . 355Configuring fibre-channel adapters . . . . . 355Configuring SCSI adapters for ESS devices . . 355

Installing SDD . . . . . . . . . . . . . 355Installing for the first time . . . . . . . . 355

x Multipath Subsystem Device Driver User's Guide

Installing SDD from CD-ROM. . . . . . 356Installing SDD from downloaded code . . . 356

Upgrading SDD . . . . . . . . . . . 357Displaying the current version of the SDD. . . 357

Configuring the SDD . . . . . . . . . . . 357Maximum number of LUNs . . . . . . . 357Adding paths to SDD devices . . . . . . . 357

Reviewing the existing SDD configurationinformation . . . . . . . . . . . . 358Installing and configuring additional paths 359Verifying additional paths are installedcorrectly . . . . . . . . . . . . . 359

Adding or modifying a multipath storageconfiguration to the supported storage device . 361

Reviewing the existing SDD configurationinformation . . . . . . . . . . . . 361Adding new storage to an existingconfiguration . . . . . . . . . . . 362Verifying that new storage is installedcorrectly . . . . . . . . . . . . . 362

Uninstalling the SDD. . . . . . . . . . . 363Using high-availability clustering on an ESS . . . 363

Special considerations in the high-availabilityclustering environment . . . . . . . . . 364Configuring a Windows NT cluster with theSDD installed . . . . . . . . . . . . 364

Making the MoveGroup Service startup typeautomatic . . . . . . . . . . . . 366

SDD server daemon . . . . . . . . . . . 366Verifying that the SDD server has started . . . 366Starting the SDD server manually . . . . . 366Changing to a different port number for theSDD server . . . . . . . . . . . . . 366Stopping the SDD server . . . . . . . . 367

Chapter 9. Using the SDD on aWindows 2000 host system . . . . . 369Verifying the hardware and software requirements 369

Unsupported environments. . . . . . . . 369Supported storage device requirements . . . . 369Host system requirements . . . . . . . . 370

Fibre-channel requirements . . . . . . . 370Preparing for an SDD installation . . . . . . 371

Configuring the supported storage device . . . 371Configuring fibre-channel adapters . . . . . 371Configuring SCSI adapters for ESS devices . . 371



Upgrading SDD . . . . . . . . . . . 374Displaying the current version of SDD . . . . 374

Configuring SDD . . . . . . . . . . . . 375Maximum number of LUNs . . . . . . . 375Verifying the configuration . . . . . . . . 375Activating additional paths . . . . . . . . 376Verifying that additional paths are installedcorrectly . . . . . . . . . . . . . . 376

Uninstalling SDD . . . . . . . . . . . . 377SAN boot support . . . . . . . . . . . . 378

Booting from a SAN device with Windows 2000and the SDD using Qlogic HBA orlater . . . . . . . . . . . . . . . 378Booting from a SAN device with Windows 2000and the SDD using an Emulex HBA or later . . . . . . . . 379Limitations when you boot from a SAN bootdevice on a Windows 2000 host . . . . . . 380SAN boot disk migration . . . . . . . . 381

Support for Windows 2000 clustering . . . . . 381Special considerations in the Windows 2000clustering environment . . . . . . . . . 381Configuring a Windows 2000 cluster with theSDD installed . . . . . . . . . . . . 382Upgrading the SDD in a two-node clusterenvironment. . . . . . . . . . . . . 382Uninstalling the SDD in a two-node clusterenvironment. . . . . . . . . . . . . 383

SDD server daemon . . . . . . . . . . . 383Verifying if the SDD server has started . . . . 383Starting the SDD server manually . . . . . 383Changing to a different port number for theSDD server . . . . . . . . . . . . . 384Stopping the SDD server . . . . . . . . 384

Chapter 10. Using SDD on a WindowsServer 2003 host system . . . . . . 385Verifying the hardware and software requirements 385

Unsupported environments. . . . . . . . 385Disk storage system requirements . . . . . 385Host system requirements . . . . . . . . 386

SCSI requirements . . . . . . . . . . 386Fibre-channel requirements . . . . . . . 386

Preparing for SDD installation. . . . . . . . 387Configuring the supported storage device . . . 387Configuring fibre-channel adapters . . . . . 387Configuring SCSI adapters for ESS devices . . 388



Upgrading the SDD . . . . . . . . . . 391Displaying the current version of the SDD. . . 391Upgrading from a Windows NT host system toWindows Server 2003. . . . . . . . . . 392

Configuring the SDD . . . . . . . . . . . 392Maximum number of LUNs . . . . . . . 392Verifying the configuration . . . . . . . . 392Activating additional paths . . . . . . . . 393Verifying that additional paths are installedcorrectly . . . . . . . . . . . . . . 394

Uninstalling the SDD. . . . . . . . . . . 395SAN boot support . . . . . . . . . . . . 396

Booting a SAN device with Windows Server2003 and the SDD using Qlogic HBA or later . . . . . . . . . . . . 396Booting a SAN device with IA64-bit WindowsServer 2003 and the SDD using a Qlogic HBA . 397Booting from a SAN device with WindowsServer 2003 and SDD using an EMULEX HBA or later . . . . 398

Contents xi

SAN boot disk migration . . . . . . . . 399Support for Windows Server 2003 clustering . . . 399

Special considerations in the Windows Server2003 clustering environment . . . . . . . 400Configure Windows 2003 cluster with the SDDinstalled . . . . . . . . . . . . . . 400Upgrading SDD in a two-node clusterenvironment. . . . . . . . . . . . . 401Uninstalling SDD in a two-node clusterenvironment. . . . . . . . . . . . . 401

SDD server daemon . . . . . . . . . . . 401Verifying if the SDD server has started . . . . 401Starting the SDD server manually . . . . . 402Changing to a different port number for theSDD server . . . . . . . . . . . . . 402Stopping the SDD server . . . . . . . . 402

Chapter 11. Using SDDDSM on aWindows Server 2003, WindowsServer 2008, or Windows Server 2012host system . . . . . . . . . . . . 403Verifying the hardware and software requirements 403

Unsupported environments. . . . . . . . 404Host system requirements . . . . . . . . 404

Fibre-channel requirements . . . . . . . 404Preparing for SDDDSM installation . . . . . . 405

Configuring the supported storage device . . . 405Configuring fibre-channel adapters . . . . . 405

Installing SDDDSM . . . . . . . . . . . 405Installing for the first time . . . . . . . . 405

Installing SDDDSM from CD-ROM . . . . 405Installing SDDDSM from downloaded code 407

Upgrading SDDDSM . . . . . . . . . . 408Displaying the current version of SDDDSM . . 408

Configuring SDDDSM . . . . . . . . . . 408Maximum number of LUNs . . . . . . . 408Verifying the configuration . . . . . . . . 408Activating additional paths . . . . . . . . 410Verifying that additional paths are installedcorrectly . . . . . . . . . . . . . . 410Removing additional paths . . . . . . . . 413Verifying that additional paths are removedcorrectly . . . . . . . . . . . . . . 413

Uninstalling SDDDSM . . . . . . . . . . 415SAN boot support . . . . . . . . . . . . 416

Remote boot support for 32-bit Windows Server2003, Windows Server 2008, or Windows Server2012 using a QLogic HBA . . . . . . . . 416Booting from a SAN device with WindowsServer 2003, Windows Server 2008, or WindowsServer 2012 and the SDD using an Emulex HBA 417

Support for Windows Server 2003, Windows Server2008, or Windows Server 2012 clustering . . . . 418

Special considerations in the Windows Server2003 clustering environment . . . . . . . 418Configuring a Windows Server 2003, WindowsServer 2008, or Windows Server 2012 clusterwith SDDDSM installed . . . . . . . . . 418Removing SDDDSM in a two-node clusterenvironment. . . . . . . . . . . . . 419

SDDDSM datapath command support . . . . . 420SDDDSM server daemon . . . . . . . . . 420

Verifying if the SDDDSM server has started . . 421Starting the SDDDSM server manually . . . . 421Changing to a different port number for theSDDDSM server . . . . . . . . . . . 421Stopping the SDDDSM server . . . . . . . 421

Chapter 12. Using the SDD server andthe SDDPCM server. . . . . . . . . 423SDD server daemon . . . . . . . . . . . 423

Understanding how the SDD server daemonworks . . . . . . . . . . . . . . . 423

Path reclamation . . . . . . . . . . 423Path probing . . . . . . . . . . . 423sddsrv and the IBM TotalStorage ExpertV.2.1.0 . . . . . . . . . . . . . . 424sddsrv and IBM TotalStorage support forGeographically Dispersed Sites for MicrosoftCluster Service . . . . . . . . . . . 424

SDDPCM server daemon . . . . . . . . . 425sddsrv.conf file format . . . . . . . . . . 425pcmsrv.conf file format . . . . . . . . . . 426Enabling or disabling the sddsrv or pcmsrvTCP/IP port. . . . . . . . . . . . . . 427Changing the sddsrv or pcmsrv TCP/IP portnumber . . . . . . . . . . . . . . . 427Disabling the probing function in sddsrv . . . . 427Changing the probing interval in sddsrv . . . . 428

Chapter 13. Using the datapathcommands . . . . . . . . . . . . 429datapath clear device count . . . . . . . . 431datapath disable ports . . . . . . . . . . 432datapath enable ports . . . . . . . . . . 433datapath open device path . . . . . . . . . 434datapath query adapter . . . . . . . . . . 436datapath query adaptstats . . . . . . . . . 438datapath query device . . . . . . . . . . 439datapath query devstats . . . . . . . . . . 442datapath query essmap . . . . . . . . . . 444datapath query portmap. . . . . . . . . . 446datapath query version . . . . . . . . . . 448datapath query wwpn . . . . . . . . . . 449datapath remove adapter . . . . . . . . . 450datapath remove device path . . . . . . . . 451datapath set adapter . . . . . . . . . . . 453datapath set device policy . . . . . . . . . 454datapath set device path. . . . . . . . . . 455datapath set qdepth . . . . . . . . . . . 456

Appendix A. SDD, SDDPCM, andSDDDSM data collection for problemanalysis. . . . . . . . . . . . . . 457Enhanced trace capability for the SDD andSDDDSM. . . . . . . . . . . . . . . 457

Using sddgetdata to collect information forproblem determination . . . . . . . . . 457

Enhanced trace capability for SDDPCM . . . . 458

xii Multipath Subsystem Device Driver User's Guide

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dbadaveHighlight

Using sddpcmgetdata to collect information forproblem determination . . . . . . . . . 459

Appendix B. System log messages 461AIX error and information messages . . . . . 461SDDPCM error log messages . . . . . . . . 462Windows log messages . . . . . . . . . . 464

Notices . . . . . . . . . . . . . . 465Trademarks . . . . . . . . . . . . . . 467

IBM license agreement for machine code . . . . 467

Glossary . . . . . . . . . . . . . 471

Index . . . . . . . . . . . . . . . 493

Contents xiii

xiv Multipath Subsystem Device Driver User's Guide

Figures1. Multipath connections between a host system

and the disk storage in a disk storage system . 52. Multipath connections between a host system

and the disk storage with the SAN VolumeController . . . . . . . . . . . . . 6

3. SDDPCM in the protocol stack . . . . . . 1004. Workload imbalance when one link receives

twice the load of the other links . . . . . 1285. Workload imbalance when one link is more

heavily loaded than another link . . . . . 1296. Workload imbalance when one host sharing

workload across two paths loses one path . . 1297. Example showing ESS devices to the host and

path access to the ESS devices in a successfulSDD installation on a Windows 2000 hostsystem . . . . . . . . . . . . . . 373

8. Example showing ESS devices to the host andpath access to the ESS devices in a successfulSDD installation on a Windows Server 2003host system . . . . . . . . . . . . 390

9. Example showing SAN Volume Controllerdevices to the host and path access to theSAN Volume Controller devices in asuccessful SDDDSM installation on aWindows Server 2003 host system . . . . 407

Copyright IBM Corp. 1999, 2013 xv

xvi Multipath Subsystem Device Driver User's Guide

Tables1. SDD platforms on supported storage devices 12. SDD in the protocol stack . . . . . . . . 33. Package-naming relationship between SDD

1.3.3.x and SDD 1.4.0.0 (or later) . . . . . 124. SDD 1.4.0.0 (or later) installation packages for

different AIX OS levels and the supported AIXkernel mode, application mode, and interface . 20

5. Major files included in the SDD installationpackage . . . . . . . . . . . . . . 22

6. List of previously installed installationpackages that are supported with theinstallation upgrade. . . . . . . . . . 25

7. Maximum LUNs allowed for different AIX OSlevels . . . . . . . . . . . . . . 39

8. Recommended maximum paths supported fordifferent number of LUNs on AIX 5.2 or later . 39

9. Recommended SDD installation packages andsupported HACMP modes for SDD versionsearlier than SDD 1.4.0.0 . . . . . . . . 55

10. Software support for HACMP 4.5 on AIX 4.3.3(32-bit only), 5.1.0 (32-bit and 64-bit), 5.2.0(32-bit and 64-bit) . . . . . . . . . . 55

11. Software support for HACMP 4.5 on AIX 5.1.0(32-bit and 64-bit kernel) . . . . . . . . 56

12. PTFs for APARs on AIX with fibre-channelsupport and the SDD server daemon running . 69

13. SDD-specific SMIT panels and how to proceed 8214. Commands . . . . . . . . . . . . 14515. SDD installation scenarios . . . . . . . 18916. Patches necessary for proper operation of

SDD on HP-UX . . . . . . . . . . . 19017. SDD components installed for HP-UX host

systems . . . . . . . . . . . . . 20018. System files updated for HP-UX host systems 20019. SDD commands and their descriptions for

HP-UX host systems . . . . . . . . . 20120. SDD components for a Linux host system 21921. Summary of SDD commands for a Linux host

system . . . . . . . . . . . . . . 22022. SDD installation scenarios . . . . . . . 32823. Operating systems and SDD package file

names . . . . . . . . . . . . . . 32824. SDD components installed for Solaris host

systems . . . . . . . . . . . . . 33125. System files updated for Solaris host systems 33226. SDD commands and their descriptions for

Solaris host systems . . . . . . . . . 33327. Windows 2000 clustering SCSI-2

Reserve/Release and PersistentReserve/Release support with MSCS . . . 381

28. Commands . . . . . . . . . . . . 429

Copyright IBM Corp. 1999, 2013 xvii

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xviii Multipath Subsystem Device Driver User's Guide

About this guideThe IBM System Storage Multipath Subsystem Device Driver (SDD) supports astorage-redundant configuration environment for a host system that is attached tostorage devices. It provides enhanced data availability, dynamic input/output(I/O) load balancing across multiple paths, and automatic path-failover protectionfor the following host systems:v IBM AIX

v HP-UXv Supported Linux distributions, levels, and architecturesv Novell Netwarev Sun Solarisv Microsoft Windows NTv Microsoft Windows 2000v Microsoft Windows Server 2003v Microsoft Windows Server 2008v Microsoft Windows Server 2012

The IBM System Storage Multipath Subsystem Device Driver Path Control Module(SDDPCM) provides AIX Multipath I/O (MPIO) support. It is a loadable module.During the configuration of supported storage devices, SDDPCM is loaded andbecomes part of the AIX MPIO Fibre Channel protocol device driver. The AIXMPIO-capable device driver with the SDDPCM module provides the samefunctions that SDD provides.

The IBM System Storage Multipath Subsystem Device Driver Device SpecificModule (SDDDSM) provides multipath I/O support for Windows platforms basedon the MPIO technology provided by Microsoft.

Who should use this guideThis guide is intended for users who will install and configure IBM SystemStorage Multipath Subsystem Device Driver (SDD), IBM System Storage MultipathSubsystem Device Driver Path Control Module (SDDPCM), or IBM System StorageMultipath Subsystem Device Driver Device Specific Module (SDDDSM). Theinstaller of SDD, SDDPCM, or SDDDSM should be:v Familiar with the operating systems on which the driver will be installedv Familiar with the storage systems on which the driver will be operatedv Familiar with the applications used with the driverv Aware of the procedures in this documentv Aware of related installation and service publications

Summary of changesThis guide contains information that was published in the IBM System StorageMultipath Subsystem Device Driver User's Guide and technical updates in thatinformation. All changes to this guide are marked with a vertical bar (|) in the leftmargin.

Copyright IBM Corp. 1999, 2013 xix

|

Note: For the more recent updates that are not included in this guide, go to theSDD website at:

www.ibm.com/servers/storage/support/software/sdd

Updated informationWith SDDDSM version 2.4.3.3-5, SDD extends support to the Microsoft WindowsServer 2012 platform. With SDDDSM version 2.4.3.4, the logging feature isenhanced to dynamically configure the size and count of the log files. Two newparameters max_log_size and max_log_count are added to the sddsrv.conf file.

Changes to this edition also include an update to the descriptions of themax_log_size and max_log_count parameters in the pcmsrv.conf file.

Command syntax conventionsThis section describes the notational conventions that this book uses.

Highlighting conventionsThe following typefaces are used to show emphasis:

boldfaceText in boldface represents menu items and command names.

italics Text in italics is used to emphasize a word. In command syntax, it is usedfor variables for which you supply actual values.

monospaceText in monospace identifies the commands that you type, samples ofcommand output, examples of program code or messages from the system,and configuration state of the paths or volumes (such as Dead, Active,Open, Closed, Online, Offline, Invalid, Available, Defined).

Special characters conventionsThe following special character conventions are used in this book:

* asterisksAsterisks (*) are used as wildcard symbols to search for the beginning orremaining characters of the installation package name.

For example, the asterisks in the beginning and at the end of Sddcharacters in the lslpp -l *Sdd* command are used as wildcard symbolsto search for the characters ibm... and ...rte.

... ellipsisEllipsis indicates that more commands are in the next command line.

< > Indicate optional parameters.

Related informationThe tables in this section list and describe the following publications:v The publications for the IBM TotalStorage Enterprise Storage Server (ESS)library

v The publications for the IBM System Storage DS8000 libraryv The publications for the IBM System Storage DS6000 library

xx Multipath Subsystem Device Driver User's Guide

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v The publications for the IBM System Storage DS5000 and DS Storage Managerlibrary

v The publications for the IBM System Storage DS4000 libraryv The publications for the IBM System Storage SAN Volume Controller libraryv The publications for the IBM Tivoli Storage Productivity Center and IBM TivoliStorage Productivity Center for Replication libraries

v Other IBM publications that relate to the ESSv Non-IBM publications that relate to the ESS

See Ordering IBM publications on page xxvi for information about how to orderpublications. See How to send your comments on page xxvi for informationabout how to send comments about the publications.

The ESS libraryThe following customer publications make up the ESS library. Unless otherwisenoted, these publications are available in Adobe portable document format (PDF)on a compact disc (CD) that comes with the ESS. If you need additional copies ofthis CD, the order number is SK2T-8803. These publications are also available asPDF files by clicking the Documentation link on the following ESS website:

http://www-947.ibm.com/systems/support/

See IBM Publications Center on page xxvi for information about ordering theseand other IBM publications.

Title DescriptionOrdernumber

IBM TotalStorageEnterprise StorageServer CopyServicesCommand-LineInterface Reference

This guide describes the commands that you can usefrom the ESS Copy Services command-line interface(CLI) for managing your ESS configuration and CopyServices relationships. The CLI application provides a setof commands that you can use to write customizedscripts for a host system. The scripts initiate predefinedtasks in an ESS Copy Services server application. You canuse the CLI commands to indirectly control Peer-to-PeerRemote Copy (PPRC) and IBM FlashCopy configurationtasks within an ESS Copy Services server group.

SC26-7494(See Note.)

IBM TotalStorageEnterprise StorageServerConfigurationPlanner forOpen-SystemsHosts

This guide provides guidelines and work sheets forplanning the logical configuration of an ESS that attachesto open-systems hosts.


IBM TotalStorageEnterprise StorageServerConfigurationPlanner for S/390

and IBM EserverzSeries Hosts

This guide provides guidelines and work sheets forplanning the logical configuration of an ESS that attachesto either the IBM S/390 or IBM Eserver zSeries hostsystem.


About this guide xxi

Title DescriptionOrdernumber

IBM TotalStorageEnterprise StorageServer HostSystemsAttachment Guide

This guide provides guidelines for attaching the ESS toyour host system and for migrating to fibre-channelattachment from either a Small Computer SystemInterface (SCSI) or from the IBM SAN Data Gateway.


IBM TotalStorageEnterprise StorageServer Introductionand PlanningGuide

This guide introduces the ESS product and lists thefeatures you can order. It also provides guidelines forplanning the installation and configuration of the ESS.

GC26-7444

IBM TotalStorageStorage SolutionsSafety Notices

This publication provides translations of the dangernotices and caution notices that IBM uses in ESSpublications.

GC26-7229

IBM TotalStorageEnterprise StorageServer SCSICommandReference

This publication describes the functions of the ESS. Itprovides reference information, such as channelcommands, sense bytes, and error recovery proceduresfor UNIX, IBM Application System/400 (IBM AS/400),and IBM Eserver iSeries 400 hosts.

SC26-7297

IBM TotalStorageEnterprise StorageServer SubsystemDevice DriverUser's Guide

This publication describes how to use the IBMTotalStorage ESS Subsystem Device Driver (SDD) onopen-systems hosts to enhance performance andavailability on the ESS. SDD creates redundant paths forshared LUNs. SDD permits applications to run withoutinterruption when path errors occur. It balances theworkload across paths, and it transparently integrateswith applications.

SC26-7637

IBM TotalStorageEnterprise StorageServer User'sGuide

This guide provides instructions for setting up andoperating the ESS and for analyzing problems.


IBM TotalStorageEnterprise StorageServer WebInterface User'sGuide

This guide provides instructions for using the two ESSWeb interfaces: ESS Specialist and ESS Copy Services.


IBM TotalStorageCommonInformation ModelAgent for theEnterprise StorageServer Installationand ConfigurationGuide

This guide introduces the common interface model (CIM)concept and provides instructions for installing andconfiguring the CIM agent. The CIM agent acts as anopen-system standards interpreter, providing a way forother CIM-compliant storage resource managementapplications (IBM and non-IBM) to interoperate witheach other.

GC35-0485

IBM TotalStorageEnterprise StorageServer ApplicationProgrammingInterface Reference

This reference provides information about the ESSapplication programming interface (API).

GC35-0489

Note: No hardcopy book is produced for this publication. However, a PDF file is availablefrom http://www-947.ibm.com/systems/support/.

xxii Multipath Subsystem Device Driver User's Guide

The DS8000 libraryThe following publications make up the IBM System Storage DS8000 library. Thesepublications are available from www.elink.ibmlink.ibm.com/public/applications/publications/cgibin/pbi.cgi.

Title Order number

IBM System Storage DS8000 Introduction and PlanningGuide

GC35-0515

IBM System Storage DS Command-Line InterfaceUser's Guide for the DS6000 series and DS8000 series

GC53-1127

IBM System Storage DS8000 Host Systems AttachmentGuide

SC26-7917

IBM System Storage DS Application ProgrammingInterface 5.4.1 and 5.4.2 Installation and Reference

GC35-0516

IBM CIM Agent for DS Open Application ProgrammingInterface 5.5

GC26-7929


Title Order number

IBM System Storage DS6000 Installation,Troubleshooting, and Recovery Guide

GC26-7925

IBM System Storage DS6000 Introduction and PlanningGuide

GC26-7924

IBM System Storage DS6000 Host System AttachmentGuide

GC26-7923

IBM System Storage DS6000 Messages Reference GC26-7920

IBM System Storage DS Command-Line Interface User'sGuide for the DS6000 series and DS8000 series

GC53-1127

IBM System Storage DS6000 Quick Start Guide GC26-7921

The DS5000 and DS Storage Manager libraryThe following publications make up the IBM System Storage DS5000 and DSStorage Manager library. These publications are available fromwww.elink.ibmlink.ibm.com/public/applications/publications/cgibin/pbi.cgi.

Title Order number

IBM System Storage DS Storage Manager Version 10.xInstallation and Host Support Guide

GC53-1135

IBM System Storage DS Storage Manager Version 10.xCopy Services Guide

GC53-1136

IBM System Storage DS4000/DS5000 Fibre Channeland Serial ATA Intermix Premium Feature InstallationOverview

GC53-1137

IBM System Storage DS5100 and DS5300 Installation,User's and Maintenance Guide

GC53-1140

About this guide xxiii

Title Order number

IBM System Storage EXP5000 Storage ExpansionEnclosure Installation, Users, and Maintenance Guide

GC53-1141

IBM System Storage DS Storage ManagerCommand-Line Programming Guide

GC52-1275

IBM System Storage DS5000 Quick Start Guide: QuickReference for the DS5100, DS5300 and EXP5000

GC53-1134

IBM TotalStorage DS4300 Fibre Channel StorageSubsystem Installation, Users, and Maintenance Guide

GC26-7722


Title Order number

IBM System Storage DS4000 Storage Manager ConceptsGuide

GC26-7734

IBM System Storage DS4000 Storage Manager 10Installation and Host Support Guide

GA76-0422

IBM System Storage DS4000 Storage Manager CopyServices Guide

GC27-2172

IBM System Storage DS4000 Storage Manager FibreChannel and Serial ATA Intermix Premium FeatureInstallation Overview

GC26-7907

IBM System Storage DS4000 Hard Drive and StorageExpansion Enclosure Installation and Migration Guide

GC26-7849

IBM System Storage DS3000/DS4000 Command-LineProgramming Guide

GC52-1275

IBM System Storage DS4000 EXP420 StorageExpansion Unit Installation, User's and MaintenanceGuide

GC27-2050

IBM System Storage DS4000 EXP810 StorageExpansion Enclosure Installation, User's andMaintenance Guide

GC26-7798

IBM TotalStorage DS4000 EXP700 and EXP710 StorageExpansion Enclosures Installation, Users, andMaintenance Guide

GC26-7735

IBM System Storage DS4200/DS4700 Quick StartGuide

GC27-2147

IBM System Storage DS4700 Installation, User's andMaintenance Guide

GC26-7843

IBM System Storage DS4800 Quick Start Guide GC27-2148

IBM System Storage DS4800 Installation, User's andMaintenance Guide

GC26-7845

IBM System Storage DS4800 Controller Cache UpgradeKit Instructions

GC26-7774

xxiv Multipath Subsystem Device Driver User's Guide

The SAN Volume Controller libraryThe following publications make up the SAN Volume Controller library. Unlessotherwise noted, these publications are available in Adobe PDF from the followingwebsite:

http://www.ibm.com/storage/support/2145

Title Order number

IBM System Storage SAN Volume Controller PlanningGuide

GA32-0551

IBM System Storage SAN Volume Controller Model2145-8A4 Hardware Installation Guide

GC27-2219

IBM System Storage SAN Volume Controller Model2145-CF8 Hardware Installation Guide

GC521356

IBM System Storage SAN Volume Controller SoftwareInstallation and Configuration Guide

SC23-6628

IBM System Storage SAN Volume ControllerCommand-Line Interface User's Guide

SC26-7903

IBM System Storage SAN Volume Controller CIMAgent Developer's Guide

SC23-6665

IBM System Storage SAN Volume Controller HostAttachment Guide

SC26-7905

IBM System Storage SAN Volume ControllerTroubleshooting Guide

GC27-2227

IBM System Storage SAN Volume Controller HardwareMaintenance Guide

GC27-2226

The Tivoli Storage Productivity Center and Tivoli StorageProductivity Center for Replication libraries

The following publications make up the Tivoli Storage Productivity Center andTivoli Storage Productivity Center for Replication libraries. These publications areavailable from the following website:

http://www-05.ibm.com/e-business/linkweb/publications/servlet/pbi.wss

Title Order number

IBM Tivoli Storage Productivity Center and IBM TivoliStorage Productivity Center for Replication Installationand Configuration Guide

SC27-2337

IBM Tivoli Storage Productivity Center User's Guide SC27-2338

IBM Tivoli Storage Productivity Center Messages SC27-2340

IBM Tivoli Storage Productivity Center Command-LineInterface Reference

SC27-2339

IBM Tivoli Storage Productivity Center ProblemDetermination Guide

GC27-2342

IBM Tivoli Storage Productivity Center WorkflowUser's Guide

SC27-2341

About this guide xxv

Ordering IBM publicationsThis section tells you how to order copies of IBM publications and how to set up aprofile to receive notifications about new or changed publications.

IBM Publications CenterThe Publications Center is a worldwide central repository for IBM productpublications and marketing material.

The IBM Publications Center offers customized search functions to help you findthe publications that you need. Some publications are available for you to view ordownload at no charge. You can also order publications. The Publications Centerdisplays prices in your local currency. You can access the IBM Publications Centerthrough the following website:

http://www-05.ibm.com/e-business/linkweb/publications/servlet/pbi.wss

How to send your commentsYour feedback is important to help us provide the highest quality information. Ifyou have any comments about this book, you can submit them in one of thefollowing ways:v E-mail Internet: [email protected] IBMLink from U.S.A.: STARPUBS at SJEVM5 IBMLink from Canada: STARPUBS at TORIBM IBM Mail Exchange: USIB3WD at IBMMAILBe sure to include the name and order number of the book and, if applicable,the specific location of the text you are commenting on, such as a page numberor table number.

v Mail or faxFill out the Readers' Comments form (RCF) at the back of this book. Return it bymail or fax (1-800-426-6209), or give it to an IBM representative. If the RCF hasbeen removed, you can address your comments to:

International Business Machines CorporationRCF Processing DepartmentDepartment 61C9032 South Rita RoadTucson, Arizona 85775-4401U.S.A.

xxvi Multipath Subsystem Device Driver User's Guide

Chapter 1. Overview of the SDDThe IBM System Storage Multipath Subsystem Device Driver (SDD) supports astorage-redundant configuration environment for a host system that is attached tothe following devices:v IBM TotalStorage Enterprise Storage Server (ESS)v IBM System Storage DS8000v IBM System Storage DS6000v IBM System Storage SAN Volume Controllerv IBM System Storage DS5000v IBM System Storage DS4000v IBM BladeCenter S SAS RAID Controller Module (RSSM)v IBM System Storage DS3950

This guide uses the following terminology:v The phrase supported storage devices refers to the following types of devices: RSSM DS3950, DS4100 (AIX only), DS4200, DS4300, DS4500, DS4700, DS4800,

DS5020, DS5100, DS5300, DS6000, and DS8000 ESS SAN Volume Controller

v The phrase disk storage system refers to ESS, DS8000, or DS6000 devices.v The phrase virtualization product refers to the SAN Volume Controller. Table 1indicates the products that different SDD platforms support.

v The phrase DS4000 refers to DS4100 (AIX only), DS4200, DS4300, DS4500,DS4700, and DS4800 devices.

v The phrase DS5000 refers to DS5100 and DS5300 devices.v The phrase RSSM refers to IBM BladeCenter S SAS RAID Controller Moduledevices.

v The phrase Open HyperSwap refers to Open HyperSwap replication.v The phrase Open HyperSwap device refers to pair of volumes that are managed ina Tivoli Productivity Center for Replication copy set.

v The phrase Open HyperSwap session refers to a collection of Tivoli ProductivityCenter for Replication managed copy sets.

Table 1. SDD platforms on supported storage devicesSupported storage device

Platform ESS DS8000 DS6000 DS5000 DS4000 DS3950 RSSM

SANVolume

Controller

AIX SDD U U U U

AIXSDDPCM

U U U U U U U U

HP U U U U U U U

Linux U U U U

Copyright IBM Corp. 1999, 2013 1

|

Table 1. SDD platforms on supported storage devices (continued)Supported storage device

Platform ESS DS8000 DS6000 DS5000 DS4000 DS3950 RSSM

SANVolume

Controller

Novell U U U

SUN U U U U

WindowsNT SDD

U U

Windows2000 andWindows2003 SDD

U U U U

Windows2003,Windows2008, andWindows2012SDDDSM

U U U U U

The SDD supports a storage-redundant configuration environment for a hostsystem that is attached to storage devices. It provides enhanced data availability,dynamic input/output (I/O) load-balancing across multiple paths, and automaticpath failover protection.

This guide provides step-by-step procedures on how to install, configure, and useSDD features on the following host systems:v IBM AIX (SDD and SDDPCM)v HP-UXv Supported Linux distributions, levels, and architectures. For up to dateinformation about specific kernel levels supported in this release, see theReadme file on the CD-ROM or visit the SDD website:www.ibm.com/servers/storage/support/software/sdd

v Novell Netware (disk storage systems only)v Sun Solarisv Microsoft Windows NT, Windows 2000, or Windows 2003 SDDv Microsoft Windows Server 2003 or Windows Server 2008 SDDv Microsoft Windows Server 2003, Windows Server 2008, or Windows Server 2012SDDDSM

The SDD architectureThe SDD is a software solution to support the multipath configurationenvironments in supported storage devices. It resides in a host system with thenative disk device driver and provides the following functions:v Enhanced data availabilityv Dynamic input/output (I/O) load-balancing across multiple pathsv Automatic path failover protectionv Concurrent download of licensed machine code

2 Multipath Subsystem Device Driver User's Guide

|

|||||||

||||||||

||

Table 2 shows the position of the SDD in the protocol stack. I/O operations thatare sent to the SDD proceed to the host disk driver after path selection. When anactive path experiences a failure (such as a cable or controller failure), the SDDdynamically switches to another path.

Table 2. SDD in the protocol stack

S008996Q

Raw disk I/O

SubsystemDevice Driver

AIX SCSI/FCPdisk driver

SCSI/FCPadapter driver

Logical VolumeManager (LVM) I/O

LVMdevice driver

S009318

Disk I/O


Linuxdisk SCSI driver

SCSIadapter driver

File system

S008998Q

Raw disk I/OLogical

Volume Manager I/0

LVMdevice driver


HP disk driver

SCSIadapter driver

S008999Q

Raw disk I/OLogical

Volume Manager I/OLVM

device driver


Sun Solarisdisk driver

SCSIadapter driver

Chapter 1. Overview of the SDD 3

Table 2. SDD in the protocol stack (continued)

S008997Q

System disk I/O


Windows NTdisk driver

adapter driver

System disk I/O

Windows 2000disk driver

adapter driver


System disk I/O

Windows Server 2003disk driver

adapter driver


This space intentionally blank

Each SDD vpath device represents a unique physical device on the storage server.Each physical device is presented to the operating system as an operating systemdisk device. There can be up to 32 operating system disk devices that represent upto 32 different paths to the same physical device.

The SDD vpath devices behave almost like native operating system disk devices.You can use most disk device operations of operating systems on the SDD vpathdevices, including commands such as open, close, dd, or fsck.

Enhanced data availabilityFigure 1 on page 5 shows a host system that is attached through small computersystem interface (SCSI) or fibre-channel adapters to a disk storage system that hasinternal component redundancy and multipath configuration. The SDD, residing inthe host system, uses this multipath configuration to enhance data availability. Thatis, when there is a path failure, the SDD reroutes I/O operations from the failing


path to an alternate operational path. This capability prevents a single failing busadapter on the host system, SCSI or fibre-channel cable, or host-interface adapteron the disk storage system from disrupting data access.

S009000Q

Host System

Port 0

SCSI / FCPadapter 0

SCSI / FCPadapter 1

Cluster 1 Cluster 2

Port 1ESS

LUN 0 LUN 1 LUN 2 LUN 3

Figure 1. Multipath connections between a host system and the disk storage in a disk storagesystem


Figure 2 shows a host system that is attached through fibre-channel adapters to aSAN Volume Controller that has internal components for redundancy andmultipath configuration. The SDD, residing in the host system, uses this multipathconfiguration to enhance data availability. That is, when there is a path failure, theSDD reroutes I/O operations from the failing path to an alternate operational path.This capability prevents a single failing bus adapter on the host system,fibre-channel cable, or host-interface adapter on the SAN Volume Controller fromdisrupting data access.

Note: SAN Volume Controller does not support parallel SCSI attachment.

Dynamic I/O load balancingBy distributing the I/O workload over multiple active paths, the SDD providesdynamic load balancing and eliminates dataflow bottlenecks. In the event of failurein one data path, the SDD automatically switches the affected I/O operations toanother active data path, ensuring path-failover protection.

Automatic path-failover protectionThe SDD failover protection feature minimizes any disruptions in I/O operationsand recovers I/O operations from a failing data path. The SDD providespath-failover protection using the following process:v Detects a path failure.v Notifies the host system of the path failure.v Selects and uses an alternate data path.

Host System

LUN 0 LUN 1 LUN 2 LUN 3

StorageDevice

FCPadapter 0

FCPadapter 1

SANVolume

ControllerFABRIC

Port 0 Port 1

Figure 2. Multipath connections between a host system and the disk storage with the SANVolume Controller


The SDD dynamically selects an alternate I/O path when it detects a software orhardware problem.

Some operating system drivers report each detected error in the system error log.With the SDD automatic path-failover feature, some reported errors are actuallyrecovered from an alternative path.

Concurrent download of licensed machine code for disk storagesystems

With the SDD multipath mode (configured with at least two paths per multipathdevice), you can concurrently download and install the licensed machine code(LMC) while applications continue to run. For certain disk storage system LMC,the disk storage system I/O bay or tower are quiesced and resumed. Its adaptersmight not respond for the duration of the service action, which could be 30minutes or more.

Note: The SDD does not support single-path mode during the concurrentdownload of LMC. Also, the SDD does not support single-path mode duringany disk storage system concurrent maintenance that impacts the pathattachment, such as a disk storage system host-bay-adapter replacement.

Attention: Do not shut down the host or reconfigure the SDD during theconcurrent download of licensed machine code or you might lose your initial SDDconfiguration.

For information about performing the concurrent download of LMC for ESS, seethe microcode installation instructions for your specific type and model.

Concurrent download of licensed machine code for virtualizationproducts

With the SDD multipath mode (configured with at least two paths per multipathdevice), you can concurrently download and install the licensed machine codewhile your applications continue to run.

At least one path must be configured through each node of a virtualizationproduct group. That is, if only two paths exist, they must go to separate nodes foreach I/O group. However, at least two paths to each node are recommended.

During the code upgrade, each node of an I/O group is upgraded sequentially.The node that is being upgraded is temporarily unavailable, and all I/O operationsto that node fail. However, failed I/O operations are directed to the other node ofthe I/O group, and applications do not see any I/O failures.


For information about performing concurrent download of LMC for virtualizationproducts, see the Configuration Guide for your specific type and model.


Concurrent download of licensed machine code for DS3950, DS4000and DS5000

If you are using the SDD multipath mode, you can concurrently download andinstall the licensed machine code while your applications continue to run, as longas you configure redundant paths to each storage controller port in addition to themultiple host adapter ports.

Because switching a device to another controller is a time-consuming recoveryaction and affects I/O performance, you can use this redundancy to avoid anunnecessary controller failover if a path fails. Therefore, configure a minimum offour paths for each LUN with two host adapter ports and two storage controllerports where each host adapter port has redundancy to each storage controller portand vice versa.


Concurrent download of licensed machine code for IBM BladeCenter SSAS RAID Controller Module (RSSM)

With the SDD multipath mode (configured with two paths per multipath device),you can concurrently download and install the licensed machine code while yourapplications continue to run.

During the code upgrade, each RSSM node is upgraded sequentially. The node thatis being upgraded is temporarily unavailable, and all I/O operations to that nodefail. However, failed I/O operations are directed to the other RSSM node, andapplications do not see any I/O failures.


Refer to RSSM documentation, at the following URL, for information aboutperforming concurrent download of LMC for RSSM:

http://www.ibm.com/systems/support/supportsite.wss/docdisplay?lndocid=MIGR-5078491&brandind=5000020

Active/Passive dual array controller path-selection algorithm forDS3950, DS4000 and DS5000 products

The DS4000 and DS5000 products are dual array controller disk subsystems. EachLUN is assigned to one controller, which is considered the owner, or the activecontroller, of a particular LUN. The other controller is considered as an alternate,or passive, controller. Thus, the SDD distinguishes the following paths to theDS4000 and DS5000 product LUN:v Paths on the ownership (active) controllerv Paths on the alternate (passive) controller

With this type of active/passive dual-controller subsystem device, I/O can be sentonly to the ownership controller. When the SDD selects paths for I/O, it selects


paths that are connected only to the ownership controller. If there is no path on theownership controller that can be used, SDD changes the LUN controller ownershipto an alternate controller, switches the paths that were passive to active, and thenselects these active paths for I/O.

Preferred node path-selection algorithm for the virtualization productsVirtualization products are two-controller disk subsystems. The SDD distinguishesthe paths to a virtualization product LUN:v Paths on the preferred controllerv Paths on the alternate controller

When the SDD selects paths for I/O, preference is always given to a path on thepreferred controller. Therefore, in the selection algorithm, an initial attempt is madeto select a path on the preferred controller. Only if no path can be used on thepreferred controller is a path selected on the alternate controller. This means thatthe SDD automatically fails back to the preferred controller any time a path on thepreferred controller becomes available during either manual or automatic recovery.Paths on the alternate controller are selected at random. If an error occurs and apath retry is required, retry paths are first selected on the preferred controller. If allretries fail on the preferred controller's paths, paths on the alternate controller areselected for retry. The following is the path selection algorithm for the SDD:1. With all paths available, I/O is only routed to paths on the preferred controller.2. If no path on the preferred controller is available, I/O failover processing to the

alternate controller occurs.3. When failover processing to the alternate controller has occurred, automatic

I/O failback processing to the preferred controller occurs if a path on thepreferred controller is available.

The following output of the datapath query device command shows that thepreferred paths are being selected and shows the format of the virtualizationproduct serial number.DEV#: 0 DEVICE NAME: Disk0 Part0 TYPE: 2145 POLICY: OPTIMIZEDSERIAL: 6005676801800005F800000000000004============================================================================Path# Adapter/Hard Disk State Mode Select Errors

0 Scsi Port4 Bus0/Disk0 Part0 OPEN NORMAL 501876 01 Scsi Port4 Bus0/Disk0 Part0 OPEN NORMAL 501238 02 Scsi Port4 Bus0/Disk0 Part0 OPEN NORMAL 0 03 Scsi Port4 Bus0/Disk0 Part0 OPEN NORMAL 0 04 Scsi Port5 Bus0/Disk0 Part0 OPEN NORMAL 499575 05 Scsi Port5 Bus0/Disk0 Part0 OPEN NORMAL 500698 06 Scsi Port5 Bus0/Disk0 Part0 OPEN NORMAL 0 07 Scsi Port5 Bus0/Disk0 Part0 OPEN NORMAL 0 0

Open HyperSwap ReplicationOpen HyperSwap replication is a special Metro Mirror replication method that isdesigned to automatically failover I/O from the primary logical devices to thesecondary logical devices in the event of a primary disk storage system failure.This function can be done with minimal disruption to the applications that areusing the logical devices.

Open HyperSwap replication applies to both planned and unplanned replicationsessions. When a session has Open HyperSwap enabled, an I/O error on theprimary site automatically causes the I/O to switch to the secondary site without


any user interaction, and with minimal application impact. In addition, while OpenHyperSwap is enabled, the Metro Mirror session supports disaster recovery. If awrite is successful on the primary site but is unable to get replicated on thesecondary site, IBM Tivoli Storage Productivity Center for Replication suspends theentire set of data consistency checking, thus ensuring that a consistent copy of thedata exists on the secondary site. If the system fails, this data might not be thelatest data, but the data should be consistent and allow the user to manuallyswitch host servers to the secondary site.

You can control Open HyperSwap from any system that is running IBM TivoliStorage Productivity Center for Replication (AIX, Windows, Linux, or z/OS).However, the volumes that are involved with Open HyperSwap must be attachedto an AIX system that is connected to IBM Tivoli Storage Productivity Center forReplication.

SDD distinguishes the paths of the source volume from the paths of the targetvolume on an Open HyperSwap copy set. With an Open HyperSwap device, I/Ocan only be sent to the source volume, so when SDD selects paths for I/O, it onlyselects paths that are connected to the source volume. If there is no path on thesource volume that can be used, SDD will initiate the Open HyperSwap request toTivoli Storage Productivity Center for Replication and work together to performthe swap. After the swap, SDD will select the target volume paths for I/O.

The following output of the pcmpath query device command shows that the targetvolume paths are being selected.DEV#: 14 DEVICE NAME: hdisk14 TYPE: 2107900 ALGORITHM: Load BalanceSESSION NAME: session1OS Direction: H1

Chapter 2. Using the SDD on an AIX host systemThis chapter provides step-by-step procedures for installing, configuring,upgrading, and removing the SDD on an AIX host system that is attached to asupported storage device.

Beginning with SDD 1.4.0.5, the SDD supports the coexistence of ESS and SANVolume Controller devices.

Beginning with SDD 1.6.0.0, the SDD supports the coexistence of all supportedstorage devices.

For updated and additional information that is not included in this chapter, see theReadme file on the CD-ROM or visit the SDD website:

www.ibm.com/servers/storage/support/software/sdd

Supported SDD featuresThe following SDD features are supported in this release:v 32- and 64-bit kernelsv Support for ESS, DS8000, DS6000 and virtualization productsv Preferred node path-selection algorithm for DS6000 and virtualization productsv Changing the SDD path-selection algorithm dynamically. Five path-selectionalgorithms are supported: Failover Round robin Round robin sequential Load balancing Load balancing sequential

v Dynamically adding paths to the SDD vpath devicesv Dynamically opening an invalid or close_dead pathv Dynamically removing or replacing PCI adapters or pathsv Fibre-channel dynamic device trackingv SDD server daemon supportv Support for HACMP

v Support for secondary-system pagingv Support for load-balancing and failover protection for AIX applications and LVMv SDD utility programsv Support for SCSI-3 persistent reserve functionsv Support for AIX trace functionsv Support more than 512 SAN Volume Controller devices from multiple SANVolume Controller clusters on an AIX host

v Storage I/O priority feature in DS6000 and DS8000, only with AIX53 TL04 orlater and with 64-bit kernel

v Two types of reserve policies: No reserve and Persistent reserve exclusive hostv General Parallel File System (GPFS)

Copyright IBM Corp. 1999, 2013 11

v Virtual I/O Server with AIX 5.3 or laterv Dual Virtual I/O Server with AIX 5.3 or laterFor more information about Virtual I/O Server, go to the following website:http://www14.software.ibm.com/webapp/set2/sas/f/vios/documentation/home.html

Verifying the hardware and software requirementsYou must install the following hardware and software components to ensure thatthe SDD installs and operates successfully.

HardwareThe following hardware components are needed:v One or more supported storage devices.v A switch if using a SAN Volume Controller (no direct attachment allowed forSAN Volume Controller)

v Host systemv SCSI adapters and cables (for ESS only)v Fibre-channel adapters and cables

SoftwareThe following software components are needed:v AIX operating system.Starting with SDD 1.6.1.0, the SDD package for AIX 5.3 (devices.sdd.53.rte)requires AIX53 TL04 with APAR IY76997.Starting with SDD 1.6.2.0, the SDD package for AIX 5.2 (devices.sdd.52.rte)requires AIX52 TL08 or later and the SDD package for AIX 5.3(devices.sdd.53.rte) requires AIX53 TL04 or later.

v SCSI and fibre-channel device driversv ibm2105.rte package for ESS devices (devices.scsi.disk.ibm2105.rte ordevices.fcp.disk.ibm2105.rte package if using NIM)

v devices.fcp.disk.ibm.rte for DS8000, DS6000, and SAN Volume Controller

Packages for SDD 1.4.0.0 (and later) will be using new package names in order tocomply with AIX packaging rules and allow for NIM installation. Table 3 showsthe package-naming relationship between SDD 1.3.3.x and SDD 1.4.0.0 (or later).

Table 3. Package-naming relationship between SDD 1.3.3.x and SDD 1.4.0.0 (or later)SDD 1.3.3.x SDD 1.4.0.0 (or later) Notes

ibmSdd_432.rte Not applicable Obsolete. This package hasbeen merged withdevices.sdd.43.rte.

ibmSdd_433.rte devices.sdd.43.rte Not applicable

ibmSdd_510.rte Not applicable Obsolete. This package hasbeen merged withdevices.sdd.51.rte.

ibmSdd_510nchacmp.rte devices.sdd.51.rte Not applicable

Not applicable devices.sdd.52.rte New package for AIX 5.2.0(or later).


Table 3. Package-naming relationship between SDD 1.3.3.x and SDD 1.4.0.0 (orlater) (continued)SDD 1.3.3.x SDD 1.4.0.0 (or later) Notes



sdd 1.8--3.4 user guide english version(1)

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