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IBM DS8000 manual Logical Configuration flow, Rank layer, Extent pool layer, Logical volume layer

Models: DS8000

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Figure 10-8 Diagram of how parity is striped across physical disks

Rank layer

At this level the ranks are formed. Presently only one array can make up a rank.

Extent pool layer

At this level the extent pools are formed. In Figure 10-7we show that extent pool A is made up of 2 ranks: rank 1 and rank 2. The extents in the pool are 1GB.

Logical volume layer

Layer 6 is the final level of the LUN formation. As illustrated in Figure 10-7,two LUNs were created out of extent pool A. The top LUN is made up of 12 extents, making it a 12 GB LUN. The bottom LUN is made up of 24 extents, making it a 24 GB LUN.

Logical Configuration flow

Figure 10-9 on page 202 shows the recommended flow for performing the Logical Configuration using the GUI.

Chapter 10. The DS Storage Manager - logical configuration 201

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IBM DS8000 manual Logical Configuration flow, Rank layer, Extent pool layer, Logical volume layer

Contents

IBM TotalStorage DS8000 Series Page IBM TotalStorage DS8000 Series Concepts and Architecture First Edition April Contents Page Benefits of virtualization Vi DS8000 Series Concepts and Architecture Summary Viii DS8000 Series Concepts and Architecture Page Page Index Xii DS8000 Series Concepts and Architecture Copyright License Dfsort TrademarksTeam that wrote this redbook PrefaceXvi DS8000 Series Concepts and Architecture Preface Xviii DS8000 Series Concepts and Architecture Comments welcome Become a published authorXx DS8000 Series Concepts and Architecture Part 1 Introduction DS8000 Series Concepts and Architecture Introduction to the DS8000 series Business Continuity DS8000, a member of the TotalStorage DS familyOverview of the DS8000 series Infrastructure SimplificationDS8000 Base frame Hardware overview IBM Standby Capacity on Demand offering for the DS8000 Storage capacityStorage system logical partitions LPARs Storage Hardware Management Console S-HMC for the DS8000Resiliency Family for Business Continuity Supported environmentsIBM TotalStorage Metro Mirror Synchronous Pprc IBM TotalStorage FlashCopyIBM TotalStorage Global Mirror Asynchronous Pprc Service and setupThree-site solution InteroperabilityCommon set of functions PositioningDS8000 compared to ESS IBM TotalStorage DS Storage Manager IBM TotalStorage DS Command-Line Interface DS CLICommon management functions DS8000 compared to DS6000Future directions of storage system LPARs Scalability and configuration flexibilityDS Open application programming interface Performance for zSeries Sequential Prefetching in Adaptive Replacement Cache SarcPerformance IBM TotalStorage Multipath Subsystem Device Driver SDDSummary 16 DS8000 Series Concepts and Architecture Part 2 Architecture 18 DS8000 Series Concepts and Architecture Components Base frame FramesRack operator panel Expansion frameRack operator panel ArchitectureSAN fabric Cache management Server-based SMP designComponents Randomseq Processor complexComponents Processor memory Service processor and SpcnFront view Rear view2 I/O enclosures RIO-GRear view Disk subsystemDevice adapters DS8000 device adapter Disk enclosuresDS8000 disk enclosure Non-switched FC-AL drawbacks11 DS8000 disk enclosure Switched FC-AL advantages12 Disk enclosure switched connections DS8000 switched FC-AL implementationArrays and spares ExpansionArrays across loops 14 DS8000 switched loop layoutAAL benefits Host adaptersDDMs Remote Mirror and Copy with Escon Ficon and Fibre Channel protocol host adaptersControl units and logical paths Escon distancesFibre Channel distances Power and coolingRack Power Control cards RPC Fibre Channel supported serversBattery backup assemblies Primary power suppliesProcessor and I/O enclosure power supplies Disk enclosure power and coolingEthernet switches 42 DS8000 Series Concepts and Architecture Storage system LPARs Logical partitions Partitions Introduction to logical partitioningVirtualization Engine technology Partitioning conceptsPhysical partitioning Ppar Building blockLogical partitioning Lpar Virtual I/O Software and hardware fault isolationDynamic logical partitioning Micro-PartitioningApplication isolation Why Logically Partition?Server consolidation Production and test environmentsLpar and storage facility images DS8000 and LparIncreased flexibility of resource allocation DS8300 Model 9A2 Lpar and storage facility image 2 DS8300 Lpar implementationDS8300 Lpar resource allocation Storage facility image hardware componentsProcessor and memory allocations Storage Facility Image Processor complexRIO-G interconnect separation 4 DS8300 Model 9A2 configuration optionsModel conversion DS8300 example configurationModel conversions regarding Lpar functionality Lpar security through Power Hypervisor PhypLpar protection Power Hypervisor Lpar and Copy ServicesFlashCopy Lpar benefitsRemote mirroring Storage system LPARs Logical partitions Example of storage facility images in the DS8300 Addressing capabilities with storage facility imagesDS8300 addressing capabilities 60 DS8000 Series Concepts and Architecture RAS Storage facility image NamingStorage complex Storage unitProcessor complex Processor complex RASPermanent monitoring Reliability, availability, and serviceabilitySelf-healing Memory reliability, fault tolerance, and integrity+1 redundancy Resource deallocation Fault maskingConcurrent Maintenance Hypervisor Storage image independenceMetadata checks Server RASRIO-G a self-healing interconnect 2 I/O enclosureData flow Server failover and failbackNormal data flow FailoverFailback NVS recovery after complete power lossSingle or multiple path Host connection availabilityEnclosure Multi-pathing software SAN/FICON/ESCON switchesZSeries host connection Open systems host connectionDisk path redundancy Switched disk connectionsRAID-5 implementation in the DS8000 RAID-5 overviewRAID-10 overview RAID-5 theoryRAID-10 theory Spare creationRAID-10 implementation in the DS8000 Floating spares Predictive Failure Analysis PFAHot plugable DDMs Rack cooling fans Battery backup unitsRack power control card RPC Disk scrubbingEmergency power off EPO Building power lossPower fluctuation protection Power control of the DS8000Installation process Microcode updatesHMC considerations Management consoleDifferent code versions across storage images Virtualization concepts Storage system virtualization Virtualization definitionStorage Facility virtualization Abstraction layers for disk virtualizationPhysical layer as the base for virtualization Array sitesArray site ArraysCreation of an array RanksForming an FB rank with 1 GB extents Extent poolsServer0 CKD volumes Logical volumesFixed Block LUNs Volume with ISeries LUNs Allocation and deletion of LUNs/CKD volumesLogical subsystems LSS DB2 Address groups Volume accessHost attachment Volume groupSummary of the virtualization hierarchy 11 Host attachments and volume groups12 Virtualization hierarchy Placement of dataBenefits of virtualization 13 Optimal placement of data101 102 DS8000 Series Concepts and Architecture 103 IBM TotalStorage DS8000 model overview and scalabilityModel naming conventions DS8000 highlights2 DS8100 Model 3 DS8300 Models 922 and 9A2 Maximum configuration for the ModelIBM TotalStorage DS8000 model overview and scalability Model comparison DS8000 model comparison Designed for scalabilityScalability for capacity Large and scalable capacityComparison of models for capacity Scalability for performanceAdding DDMs Future planLinear-scalable architecture Way I/O controllersBenefit of the DS8000 for scalability RIO-GModel conversions Model upgrades114 DS8000 Series Concepts and Architecture 115 Copy ServicesCopy Services functions Introduction to Copy ServicesPoint-in-Time Copy FlashCopy Read from the target volume Read from the source volumeWrite to the source volume No background copy option Point-in-Time Copy function authorizationRefresh target volume also known as Incremental FlashCopy FlashCopy optionsIncremental FlashCopy Data Set FlashCopyData Set FlashCopy Multiple Relationship FlashCopyConsistency Group FlashCopy What is Consistency Group FlashCopy?FlashCopy Source Volume FlashCopy Target Volume FlashCopy to Pprc Primary VolumeMetro Mirror Synchronous Pprc Inband Commands over Remote Mirror linkRemote Mirror and Copy Peer-to-Peer Remote Copy Persistent FlashCopyMetro Mirror Global Copy PPRC-XDGlobal Copy Global Mirror Asynchronous PprcGlobal Mirror How Global Mirror worksGlobal Mirror How it works OS Global Mirror XRC 11 z/OS Global Mirror Secondary server12 z/OS Metro/Global Mirror Comparison of the Remote Mirror and Copy functionsGlobal Copy PPRC-XD What is data consistency? What is a Consistency Group?How does Consistency Group keep data consistency? 1st LSS13 Storage Hardware Management Console S-HMC Interfaces for Copy ServicesDS Storage Manager Web-based interface 16 DS8000 Copy Services network componentsTip What is changed from the ESS CLI? DS Command-Line Interface DS CLIDS Open application programming Interface API Future Plans Interoperability with ESS140 DS8000 Series Concepts and Architecture 141 Part 3 Planning and configuration142 DS8000 Series Concepts and Architecture 143 Installation planningGeneral considerations Packaged dimensions and weight for DS8000 modelsDelivery requirements Floor and space requirements Installation site preparation145 Meeting floor load requirements Installing on raised or nonraised floorsCalculating space requirements 147 Power requirementsPower control DS8000 dimensionsInput voltage requirements Power outlet requirementsFans and air intake areas Power connector requirementsPower consumption and environmental information Environmental requirementsAttaching to open systems hosts Host attachmentCooling the storage complex FICON-attached S/390 and zSeries hosts ESCON-attached S/390 and zSeries hosts151 Host systems attachment Where to get the updated information for host attachmentSAN Fabric products 153 Network and SAN requirementsHMC network requirements Channel extension technology productsRemote support connection requirements Remote power control requirementsSAN requirements 155 156 DS8000 Series Concepts and Architecture 157 Configuration planningStorage Hardware Management Console S-HMC Configuration planning overviewExternal S-HMC S-HMC and Ethernet switchesHMC software components Remote servicesDS Storage Manager Required ports 161HMC network topology Secure high-speed connection Dial-up connection163 Call home Remote access165 HMC security considerationsSecurity mechanism 1 Console must initiate session Security mechanism 2 Public key encryptionFTP Offload option Security mechanism 3 Login securityHMC user management 167 Operating environment license OEL required featureLicensed function indicators DS8000 licensed functionsLicense scope for each DS8000 licensed function Optional featuresOperating environment license feature codes Point-in-Time Copy function 2244 Model PTCRemote Mirror for z/OS 2244 Model RMZ Point-in-Time Copy PTC feature codesRemote Mirror and Copy RMC feature codes Remote Mirror and Copy functions 2244 Model RMCOrdering licensed functions Parallel Access Volumes 2244 Model PAVRemote Mirror for zSeries RMZ feature codes Parallel Access Volumes PAV feature codesUser authorize to FlashCopy 25 TB of CKD data 171Solution 173 Disk storage feature activationAdding storage capacity to an existing licensed function Logical configurationsCapacity planning Scenarios for managing licensingCKD RAID rank capacity 175FB RAID rank capacity Sparing rules177 Sparing examplesSparing Example 2 RAID-10 11 Sparing example 3 RAID-5 Different capacity, same RPM 179IBM Standby Capacity on Demand Standby CoD Sparing Example 4 RAID-5181 Capacity and well-balanced configurationDDM to DA Mapping -- 2-way 183 Data migration planningRemote copy technologies Basic commandsOperating system mirroring Software packages6 z/OS data migration methods Migration services and appliances185 15 Different data migration methods Planning for performanceNumber of host ports/channels Parallel Access Volumes z/OS onlyDisk Magic Size of cache storageHot spot avoidance 189 DS Storage Manager logical configurationStorage configuration terminology Configuration hierarchy, terminology, and conceptsPSeries1 PSeries2 Extent pools Array sitesArrays RanksExtent Pool Volume groups Logical volumesVolume Group Address groups Host System CExtent Pool Extent Pool Planning Array site layer Raw or physical DDM layerArray layer Extent pool layer Logical Configuration flowLogical volume layer Rank layerConnecting to the DS8000 Introducing the GUI and logical configuration panelsWelcome panel 10 Entering the URL using the TCP/IP address for the S-HMC12 The Welcome panel Real-time Manager configurationSimulated Manager configuration Copy ServicesLog Creating and defining the users and passwords15 User administration panel Using the help panels information center17 View of the information center Navigating the GUI20 View of the Storage Complexes section 19 View of the storage complexes in the work area21 Storage unit view of the pull-down Radio buttons and check boxesConfiguring a storage complex Logical configuration processConfiguring the storage unit 25 The General storage unit information panel Configuration advancement steps 28 Specify I/O adapter configuration panel 29 Create host systems, screen Configuring the logical host systems31 View of the General host information panel 33 Define host ports panel, with updated host information Click Apply assignment and OK Creating arrays from array sites36 The Definition method panel 38 The Add arrays to ranks panel with FB selected Creating extent pools39 The Definition method panel Creating FB volumes from extents41 The Select extent pool panel 42 The Define volume properties panelClick Volume Groups Creating volume groups44 The Define volume group properties filled out Assigning LUNs to the hosts Deleting LUNs and recovering space in the extent poolClick Host Systems Click Finish Creating CKD volumesClick Volumes → zSeries Creating CKD LCUsClick Storage Units Displaying the storage unit Wwnn49 View of the Wwnn in the General panel 230 DS8000 Series Concepts and Architecture 231 Functionality IntroductionSupported environments Installation methodsESS Copy Services command flow using ESS Copy Services CLI Command flowSecure sockets DS CLI command flowTCP/IP ports DS8000 split network DS6000 command flowESS CLI co-existence Command flow for the DS6000CLI co-existence Storage managementUser security Command modesSingle command mode Example 11-1 Using DS CLI via a single commandExample 11-3 Creating a DS CLI script Interactive modeScript mode Example 11-4 Using DS CLI in interactive modeUser assistance Lists all available DS CLI commandsLists all DS CLI commands with syntax information Syntax conventionsDS CLI return codes Example 11-8 Use of the help -lcommandReturn codes Man pagesUsage examples Example 11-11 Example of a configuration scriptExample 11-10 Return code examples Mixed device environments and migration Which CLI to use based on what hardware you have installedMigration considerations DS CLI migration exampleMigration tasks Determining the saved tasks to be migratedCollecting the task details A portion of the tasks listed by using the GUIUsing the GUI to get the contents of a FlashCopy task Converting the saved task to a DS CLI commandConverting a FlashCopy task to DS CLI Example 11-14 Using interactive dscli mode without profilesCreating a user ID for use only with ESS Using DS CLI commands via a single command or scriptProcedure to create an encrypted password file Setting up a profileExample 11-18 Establishing a FlashCopy with a single command Issuing a DS CLI command and scripting itExample 11-19 Creating an executable file Example 11-20 Using script mode252 DS8000 Series Concepts and Architecture 253 Performance considerationsSpeed gap between server and disk storage What is the challenge?New and enhanced functions 255 Where do we start?Pprc over Fibre Channel links Switch from Escon to Ficon portsSSA backend interconnection Arrays across loopsHow the DS8000 series overcomes FC-AL shortcomings Fibre Channel switched disk interconnection at the back endHow does the DS8000 address the challenge? FC-AL shortcomingsMemory 259 New four-port host adapters Fibre Channel device adapter261 POWER5 Heart of the DS8000 dual cluster designRIO-G Interconnect 263 RIO-G InterconnectVertical growth and scalability Performance and sizing considerations for open systems265 Workload characteristicsData placement in the DS8000 Cache size considerations for open systems266 DS8000 Series Concepts and Architecture LVM striping267 Stripe sizeDetermining the number of paths to a LUN Determining where to attach the hostSubsystem Device Driver SDD Dynamic I/O load-balancing Connect to zSeries hosts Performance and sizing considerations for z/OS269 12 DS8100 frontend connectivity example partial view Performance potential in z/OS environmentsProcessor memory size considerations for z/OS environments Appropriate DS8000 size in z/OS environments271 Or zSeries channel consolidation 273 Disk array sizing considerations for z/OS environmentsConfigure one extent pool for each single rank Configuration recommendations for z/OS275 Minimize the number of extent poolsPlan for a reasonable number of extent pools Extent pool0 Extent pool115 Mix of extent pools 277278 DS8000 Series Concepts and Architecture 279 280 DS8000 Series Concepts and Architecture 281 ZSeries software enhancements13.2 z/OS enhancements Software enhancements for the DS8000Scalability support 283 Large Volume Support LVSRead availability mask support Benefits of the scalability enhancements13.2.5 DS8000 definition to host software Initial Program Load IPL enhancementsRead control unit and device recognition for DS8000 285 New performance statisticsListdata Count Listdata Counts report of DS8000 287Listdata Status 289 Resource Management Facility RMFCoexistence considerations 13.3 z/VM enhancements13.4 z/VSE enhancements Migration considerations291 TPF enhancements292 DS8000 Series Concepts and Architecture 293 Data migration in zSeries environmentsConsolidate storage subsystems Define migration objectives in z/OS environmentsConsiderations for new logical volume size Consolidate logical volumes295 Example 14-1 Data Classes with EF attribute Dynamic Parallel Access Volumes required for large volumes297 Keep source and target volume size at the current sizeSummary of data migration objectives Data migration based on physical migrationPhysical migration with DFSMSdss and other storage software Data migration with Piper for z/OS Software- and hardware-based data migration299 Piper hardware 301 Data migration with z/OS Global MirrorBridge from Escon to Ficon with Metro/Global Copy Hardware- or microcode-based migration303 Data migration with Metro Mirror or Global CopyPprcopy DDNAMEDD02 Query Example 14-3 All data is replicated 305Example 14-5 All data is replicated 491Data migration based on logical migration Data Set Services Utility307 System utilities Hierarchical Storage Manager, DFSMShsmSMS Storage Groups migration source environment 309Storage Group Application Selection Example 14-8 Select SMS storage group in Scds311 Alter Volume Statuses Pool Copy Pool Backup onlyALL Volumes Altered Example 14-12 Confirmation about SMS volume status change313 Combine physical and logical data migration Summary of data migration 14.5 z/VM and VSE/ESA data migration315 316 DS8000 Series Concepts and Architecture 317 318 DS8000 Series Concepts and Architecture 319 Open systems support and softwareOpen systems support Where to look for updated and detailed informationSupported operating systems and servers TotalStorage Proven program DS8000 Interoperability MatrixIBM HBA Search Tool DS8000 Host Systems Attachment GuideAtto Differences to the ESSPlatform and operating system vendors’ pages Emulex CorporationAdditional supported configurations RPQ Boot supportSubsystem Device Driver DS CLI Other multipathing solutionsIBM TotalStorage Productivity Center IBM TotalStorage Productivity CenterMDM main panel Sample Device Manager view Device ManagerSample screenshot of TPC for Disk TPC for DiskTPC for Replication Global Mirror UtilityEnterprise Remote Copy Management Facility eRCMF 332 DS8000 Series Concepts and Architecture 333 Data migration in the open Systems environmentTor Host operating system-based migration Comparison of migration methodsCopy raw devices Basic copy commandsOnline copy and synchronization with rsync Migration using volume management softwareMigration using LVM mirroring Backup and restoreSubsystem-based data migration Migration using backup and restoreCombination of Metro Mirror and Global Copy Metro Mirror and Global CopyPiper migration IBM Piper migrationOther migration applications IBM migration services343 Appendix A. Open systems operating systems specificsCapacity planning considerations Data placement considerationsDS8000 Host Systems Attachment Guide PlanningIostat Unix performance monitoring toolsExample A-1 AIX iostat output Example A-2 SUN Solaris iostat output System Activity Report SARExample A-3 SAR Sample Output VmstatExample A-4 Finding Fibre Channel adapter WWN Other publicationsAIX host attachment scripts Finding the World Wide Port NamesSubsystem device driver SDD Determine the installed SDD levelUseful SDD commands Managing multiple pathsMultipath I/O Mpio Example A-7 lsvpcfg commandUseful Mpio commands Determine the installed Sddpcm levelExample A-8 lspath command result LVM mirroring LVM configurationAIX access methods for I/O LVM stripingConcurrent I/O Boot device supportAIX on IBM iSeries Direct I/OExample A-9 Filemon output file Monitoring I/O performanceIostat FilemonIBM Mpio FC Linux Getting Started with zSeries Fibre Channel Protocol Existing reference materialImplementing Linux with IBM Disk Storage Linux with zSeries and ESS EssentialsSome Linux Scsi basics Important Linux issuesTable A-1 Major numbers and special device files Example A-10 Create new special device files for Scsi disks Missing device filesLimited number of Scsi devices Managing multiple pathsScsi device assignment changes Fibre Channel disks discovered before internal Scsi disks RedHat Enterprise Linux RH-EL multiple LUN supportExample A-12 Sample /etc/modules.conf Adding FC disks dynamicallyExample A-13 SCSi disks attached at system start time Gaps in the LUN sequence Linux on IBM iSeries/proc pseudo file system Troubleshooting and monitoringExample A-16 Sample /proc/scsi/scsi file Generic Scsi tools Performance monitoring with iostatExample A-17 Sample /proc/scsi/qla2300/x Microsoft Windows 2000/2003 HBA and operating system settingsSDD for Windows Figure A-1 Microsoft VDS Architecture Windows Server 2003 VDS supportGeographically Dispersed Sites FC port configurationVolume Shadow Copy Service HP OpenVMSConfigurations Volume configurationOpenVMS volume shadowing Command Console LUNAppendix A. Open systems operating systems specifics 372 DS8000 Series Concepts and Architecture 373 Appendix B. Using DS8000 with iSeriesHardware Logical volume sizesTable B-1 OS/400 logical volume sizes Supported environmentChanging LUN protection Protected versus unprotected volumesUsing 5250 interface Adding volumes to iSeries configurationFigure B-3 Work with Disk Configuration menu Figure B-5 Confirm Add Units Adding volumes to an Independent Auxiliary Storage PoolFigure B-7 iSeries Navigator Signon to iSeries window Figure B-9 SST Signon Figure B-11 New disk pool welcome Figure B-13 Confirm disk pool configuration Figure B-15 Choose the disks to add to the Disk Pool Figure B-17 New Disk Pool Summary Figure B-20 New Disk Pool shown on iSeries Navigator Avoiding single points of failure MultipathFigure B-22 Single points of failure Configuring multipathFigure B-24 Example of multipath with iSeries Adding multipath volumes to iSeries using 5250 interfaceFigure B-25 Adding multipath volumes to an ASP Figure B-27 Adding a multipath volume Adding volumes to iSeries using iSeries NavigatorFigure B-28 New Disk Pool shown on iSeries Navigator Figure B-30 Example of multipath logical units Managing multipath volumes using iSeries NavigatorAppendix B. Using DS8000 with iSeries Figure B-32 Multipath logical unit properties Figure B-33 Multipath connections Multipath rules for multiple iSeries systems or partitionsChanging from single path to multipath Sizing guidelinesCache Planning for arrays and DDMsSize and number of LUNs Number of iSeries Fibre Channel adaptersTable B-2 Capacity per I/O Adapter Sharing ranks between iSeries and other servers Recommended number of ranksTable B-3 Disk operations per second per RAID rank Metro Mirror and Global Copy Connecting via SAN switchesMigration OS/400 mirroringOS/400 data migration Figure B-35 Using Metro Mirror to migrate from ESS to DS8000Figure B-36 Ending allocation for existing disk units FlashCopy Copy Services for iSeriesRemote Mirror and Copy AIX on IBM iSeries ISeries toolkit for Copy ServicesLinux on IBM iSeries 406 DS8000 Series Concepts and Architecture 407 Appendix C. Service and support offeringsIBM Implementation Services for TotalStorage Copy Functions IBM Web sites for service offeringsIBM service offerings IBM Implementation Services for TotalStorage disk systemsEnterprise Remote Copy Management Facility eRCMF IBM Geographically Dispersed Parallel Sysplex GdpsIBM eServer iSeries Copy Services IBM Operational Support Services Support LineAppendix C. Service and support offerings 412 DS8000 Series Concepts and Architecture Other publications IBM Redbooks413 Online resources Help from IBM How to get IBM Redbooks416 DS8000 Series Concepts and Architecture 417 IndexDS CLI OEL Escon Ficon RH-EL BBU Spcn VSE IBM TotalStorage DS8000 Series Concepts and Architecture Page Page IBM TotalStorage DS8000 Series Concepts Architecture