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  • Nutanix Complete ClusterA Technical Whitepaper

  • NUTANIX COMPLETE CLUSTER:ATECHNICALWHITEPAPER

    Table of Contents

    ExecutiveSummary............................................................................... 3

    Introduction........................................................................................... 4

    LimitationsofCurrentArchitecture........................................... 4

    TheGoogleApproach................................................................. 4

    NutanixCompleteClusterArchitecture.............................................. 6

    MainPillars.................................................................................. 6

    ArchitectureOverview................................................................ 7

    NutanixScale-OutConvergedStorageKeyComponents...... 8

    KeyFeatures........................................................................................ 11

    CapacityOptimization.............................................................. 11

    EaseofManagement................................................................ 11

    PerformanceandScalability..................................................... 12

    HighAvailability........................................................................ 13

    Conclusion........................................................................................... 15

  • EXECUTIV

    ESUMMARY

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    Executive SummaryStorageisthebiggestchallengeinvirtualizeddatacenterstoday.Thenetwork

    storagearchitecturedesignedfifteenyearsagoforphysicalserversistoo

    expensiveandcomplexforvirtualmachines.Withoutanenterprise-class

    alternative,organizationsareforcedtousetraditionalsolutions,whichcant

    keepupwithvirtualmachinesthataredynamic,growrapidlyinnumberand

    continuetodemandnewlevelsofperformanceandcapacity.

    NutanixCompleteClusterisascale-outcomputeandstorageinfrastructure

    thatallowsorganizationstovirtualizetheirdatacenterswithoutrequiring

    networkstorage(SANorNAS).Builtfromthegroundupforvirtualmachines,it

    providescompletecomputeandstoragecapabilitiesalongwithenterprise-class

    performance,scalability,availabilityanddatamanagementfeatures.Itleverages

    industry-standardhardwarecomponents,solid-statedrivesandmarket-leading

    hypervisorstoprovideanout-of-the-boxsolutionthatmakesvirtualization

    extremelyeasyandcosteffective.

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    IntroductionLimitations of Current ArchitectureOrganizationsarebuildingtheirvirtualizationinfrastructureusingthe

    traditionalservers-connected-to-storage-over-a-networkarchitecture,which

    cantadapttotheever-changingdemandsofvirtualization.Inadditiontoslow

    performance,networkstoragehasbecomethesinglebiggestsourceofcostand

    complexityinvirtualizedenvironments.Thenetworkstorage-basedarchitecture

    workedwellforphysicalserversthatservedrelativelystaticworkloads.

    Virtualization,andnowCloudComputing,hasmadedatacentersextremely

    dynamic;virtualmachinesarecreatedonthefly,movefromservertoserverand

    dependheavilyonsharedresources.Thesecharacteristicsmakethemanagement

    ofvirtualmachinesandtheirunderlyingphysicalinfrastructureextremely

    complex.

    Datavolumesaregrowingatarapidpaceinthedatacenter,thankstotheease

    ofcreatingnewVMs.Intheenterprise,newinitiativeslikedesktopvirtualization

    contributetothistrend.Serviceprovidersdealwithanevenlargernumberof

    VMsastheybuilddatacenterstoservecustomerswhocantaffordthecost

    andmanagementoverheadthatvirtualizationrequires.Thisgrowingpoolof

    VMsisexertingtremendouscost,performanceandmanageabilitypressureon

    thetraditionalarchitecturethatconnectscomputetostorageoveramulti-hop

    network.

    Theriseofsolid-statedrivesisanothertrendthatisrapidlywideningthegap

    betweencomputeandstoragetiers.UseofSSDsthatare100X-1000Xfaster

    thantraditionalharddiskswillmaketheexistingnetworkbottlenecksand

    networkcomplexityevenworse,ifvirtualmachinesneedtoaccessthemovera

    network.ManySAN/NASvendorsareaddingSSDstotheirsolutions,charginga

    heftypremiumforthesedrivesandrequiringadditionalinvestmentsinnetwork

    bandwidthtoaccessanalreadyexpensivetierofstorage.

    The Google ApproachGoogleandotherleadingcloud-generationcompaniessuchasAmazon,Yahoo

    andMicrosoft(Azure)realizedthatanetwork-storagebasedapproachwould

  • INTRODUCTIO

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    5NUTANIX COMPLETE CLUSTER:ATECHNICALWHITEPAPER

    notworkfortheirdatacenters.Theybuiltsoftwaretechnology(suchasGoogle

    FileSystem)thatcouldgluealargenumberofcommodityserverswithlocal

    storageintoasinglecluster.ThisapproachallowedGoogletobuildaconverged

    computeandstorageinfrastructurethatusedcommodityserverswithlocal

    storageasitsbuildingblock.GoogleFileSystemrunsacrossaclusterofservers

    andcreatesasinglepooloflocalstoragethatcanbeseamlesslyaccessedby

    applicationsrunningonanyserverinthecluster.Itprovideshighavailability

    toapplicationsbymaskingfailuresofharddisksandevencompleteservers.

    GoogleFileSystemallowedGoogletobuilddatacenterswithmassivelyscalable

    computeandstorage,withoutincurringthecostsandperformancelimitations

    associatedwithnetworkstorage.

    Nutanixhastakenasimilarscale-outapproachtobuildanenterprise-ready

    computeandstorageinfrastructurethatisdesignedfromthegroundupfor

    virtualmachines.

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    Nutanix Complete Cluster Architecture Main PillarsNutanixCompleteClusterwasdesignedfromscratchtosolvestoragechallenges

    forvirtualmachinesbybuildingasystemthatleveragesthelatestadvancesin

    systemarchitecture,hardwareandsoftwaretechnologies.Therearethreecore

    pillarsoftheNutanixarchitecture:

    Distributed Computing

    TheNutanixarchitectureissimilartoGooglesarchitectureinthatitisascale-

    outcomputeandstorageinfrastructurethateliminatestheneedfornetwork

    storage.Atthesametime,NutanixbuildsuponGooglesarchitectureand

    providesanenterprise-classsolution.WhileGoogleFileSystemisacustom

    solutionthatworksforGooglesinternalapplications(search,Gmail,etc.),

    Nutanixprovidesageneral-purposesolutionforvirtualizedenvironments.In

    additiontoitsscale-outcapabilities,ithasthesameorbetterenterprise-class

    datamanagementfeaturesthatarecommonlyprovidedbyadvancednetwork

    storagesolutions,includinghighavailability,backup,snapshots,anddisaster

    recovery.

    Virtualization

    TheNutanixarchitecturewasdesignedforvirtualmachinessoitsupportsall

    hypervisorfunctionsthataresupportedbythetraditionalnetwork-storage

    basedarchitecture,includingliveVMmigrationandhighavailability.In

    addition,becausetheNutanixarchitectureisVM-aware,itovercomeslimitations

    oftraditionalsolutionsthatwereoptimizedtoworkwithphysicalservers.For

    example,whilethingsaremanagedonaperVMbasisoncomputeside,theunit

    ofmanagementonstoragehastraditionallybeenaLUN.WhenaLUNisshared

    bymanyVMs,itbecomesmoredifficulttoperformstorageoperationssuchas

    backup,recovery,andsnapshotsonaper-VMbasis.Itisalsodifficulttoidentify

    performancebottlenecksinaheavily-sharedenvironmentduetothechasm

    betweencomputingandstoragetiers.TheNutanixarchitectureovercomesthese

    limitations.

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    Solid-State Drives

    TheNutanixarchitecturewasdesignedtotakeadvantageofenterprise-grade

    solid-statedrives(SSDs).Itisimportanttonotethatthetraditionalstorage

    systemsweredesignedforspinningmediaanditishardforthemtoleverage

    SSDsefficientlyduetotheentirelydifferentaccesspatternsthatSSDsprovide.

    Whileharddiskshavetodealwiththerotationandseeklatencies,SSDsdo

    nothavesuchmechanicallimitations.Thisdifferencebetweenthetwomedia

    requiresthesoftwaretobeoptimizeddifferentlyforperformance.Onecannot

    simplytakesoftwarewrittenforharddisk-basedsystemsandhopetouseit

    efficientlyonsolid-statedrives.TheNutanixarchitectureusesSSDstostorea

    varietyoffrequently-accesseddata,fromVMmetadatatoprimarydatastorage,

    bothinadistributedcacheforhigh-performanceandinpersistentstoragefor

    quickretrieval.TomaximizetheperformancebenefitsofusingSSDs,theNutanix

    architecture:

    ReservesSSDsforI/O-intensivefunctions

    Includesspace-savingtechniquesthatallowlargeamountsoflogicaldatato

    bestoredinasmallphysicalspace

    Migratescoldorinfrequently-useddatatoharddiskdrivesautomatically,

    allowsadministratorstobypassSSDsforlow-priorityVMs

    Architecture OverviewNutanixCompleteClusterisascale-outclusterofhigh-performancenodes,

    orservers,eachrunningastandardhypervisorandthatcontainsprocessors,

    memoryandlocalstorage,includingSSDs)andharddiskdrives.Eachnode

    runsvirtualmachinesjustlikeastandardvirtualmachinehost.Inaddition,

    localstoragefromallnodesisvirtualizedintoaunifiedpoolbyNutanixScale-

    outConvergedStorage(SOCS)(Figure1).Ineffect,SOCSactslikeanadvanced

    SANthatuseslocalSSDsanddisksfromallnodestostorevirtualmachinedata.

    VirtualmachinesrunningontheclusterwritedatatoSOCSasiftheywere

    writingtoaSAN.SOCSisVM-awareandprovidesadvanceddatamanagement

    features.Itbringsdataclosertovirtualmachinesbystoringthedatalocallyon

    thesystem,resultinginhigherperformanceatalowercost.NutanixComplete

    Clustercanhorizontallyscalefromafewnodestoalargenumberofnodes,

    enablingorganizationstoscaletheirinfrastructureastheirneedsgrow.

  • NUTANIX

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    8NUTANIX COMPLETE CLUSTER:ATECHNICALWHITEPAPER

    Server 1 Server 2 ..............

    FusionIO HDDs

    Virtual Machine / Virtual Disk

    Server N

    N u t a n i x S c a l e - O u t C o n v e r g e d S t o r a g e ( S O C S )

    Figure 1: Nutanix Scale-Out Converged Storage Architecture

    WithNutanixCompleteCluster,allvirtualizationfeatures,includinghigh

    availabilityandliveVMmigration,continuetoworkseamlessly.Administrators

    createvirtualmachinesonNutanixCompleteClusterusingtheirstandard

    processes.NutanixSOCSprovidesstorageforthesevirtualmachinesintheform

    ofvirtualdisks,orvDisks,whicharestandardiSCSIdevices.

    Nutanix Scale-Out Converged Storage Key ComponentsThekeytotheNutanixarchitectureisSOCSapatent-pendingscale-out

    convergedstoragelayerthathasthefollowinguniquesetofcapabilities:

    Itisconvergedwiththecomputelayer.VMsandSOCSco-existonthesame

    cluster.

    ItisVM-aware.SOCSprovisionsstorageonaper-VMbasisandcanidentifyI/O

    comingfromeachVM.

    Itcanscaleoutfromafewnodestoalargenumberofnodes.

    Ithasground-upintegrationwithsolid-statedrives.

    Itprovideshighavailabilityagainstdiskornodefailures.

    ItprovideshighperformancebymakingI/Oaccesslocal,leveragingsolid-state

    drivesandemployingaseriesofpatent-pendingperformanceoptimizations.

    Itprovidesuniquecapacityoptimizationcapabilities.

    SOCSisenabledbythefollowingcomponents:

  • NUTANIX

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    n-Way Controller Cluster

    WhiletraditionalSANsolutionstypicallyhave1,2,4or8controllers,ann-node

    NutanixCompleteClusterhasncontrollers(Figure2).EverynodeonNutanix

    CompleteClusterrunsaspecialvirtualmachine,calledaControllerVM.This

    virtualmachineactsasavirtualcontrollerforSOCS.AllControllerVMsin

    theclustercommunicatewitheachothertoformasingledistributedsystem.

    UnliketraditionalSAN/NASsolutionsthatarelimitedtoasmallnumberoffixed

    controllers,thisarchitecturecontinuestoscaleasmorenodesareadded.

    Node 1 Node 2 ..............

    SSDs HDDs

    Virtual Machine / Virtual Disk

    Node N

    Control ler VM Control ler VM Control ler VM...... . . . . . . . .

    .... ............ .... ............ .... ............

    Figure 2: Nutanix Scale-Out Controller VM Architecture

    Heat-Optimized Tiering Cache (HOTcache)

    HOTcacheisahighperformancecachebackedbySSDsfromeachnodeina

    cluster.WhenguestVMswritedata,thatdataisfirstwrittentoHOTcacheand

    then,inthebackground,itisflushedtoSOCS.HOTcacheusesasequentialdata

    layouttoprovidehighperformanceevenifworkloadsfromVMsgetmixedinto

    arandomworkload.HOTcachekeepsonedatacopyonalocalSSDandanother

    copyonadifferentnodesothatthereisnodataloss,eveninthecaseofanode

    failure.

    Distributed Metadata Service (Medusa)

    Intraditionalstoragesystems,controllersoftenbecomeabottleneckasmore

    storageisadded.Oneofthemainreasonsforthisissueisthatthestorage

    metadataisstoredonthecontrollers.Traditionalsystemsscaletoasmall

    numberofcontrollers,soasthenumberofVMsincreases,sodoestheI/Oload

    oneachcontroller.Nutanixsdistributedmetadataservice,Medusa,distributes

  • NUTANIX

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    theclustermetadataacrosstheclusterforscalabilityandreplicatesthedata

    onmultiplenodesforfaulttolerance.Theserviceishighlyavailableandcan

    toleratemultiplemodulefailures.Incomparison,traditionalsolutionsthat

    dependonafewstoragecontrollerscannottoleratemultiplecontrollerfailures.

    Distributed Data Maintenance Service (Curator)

    Nutanixsdistributeddatamaintenanceservice,Curator,isaMapReduce1

    -basedframeworkforexecutingbackgrounddatamanagementoperationsina

    massivelyparallelmanner.Suchoperationsinclude:

    Migrationofcolddatatolowertiers(forHeat-OptimizedTiering)

    Garbagecollectionofdatathathasbeendeleted

    Dataconsistencythroughroutinechecksums

    Replicationofdataincaseofnodeordiskfailures

    Re-balancingofdatawhennodesareaddedorremoved

    MigrationofdatatomaximizelocalaccesswhenaVMmovesfromonenode

    toanother

    FlashStore

    FlashStoreisthepersistent,flash-basedstorageprovidedbythepoolingof

    SSDsfromallnodesinthecluster.DataisfirstwrittentoFlashStoreandthen

    movedofftoDiskStore,asitbecomescold.Ascolddatabecomeshotagain,

    itisbroughtbackintoFlashStore.ForvDisksthatservelowpriorityVMs,

    administratorshaveanoptiontoskipFlashStore.

    DiskStore

    DiskStoreisthehigh-capacitySATAstoragetierspreadacrossthecluster.

    DiskStoreprovideslargestoragecapacityforcolddata.NutanixsHeat-

    OptimizedTiering(HOT)combinesFlashStoreandDiskStoretoprovidehigh

    performanceaswellashighcapacityatalowercost.

    1 MapReduceisatechnologyoriginallybuiltatGoogleformassivelyparallelanalysisofdatainacluster

  • KEYFEATURES

    11NUTANIX COMPLETE CLUSTER:ATECHNICALWHITEPAPER

    Key FeaturesNutanixCompleteClusternotonlyeliminatestheneedforaSAN,butitalso

    providestopofthelineavailability,performanceanddatamanagement

    features.Someofthekeyfeaturesaredescribedbelow.

    Capacity OptimizationNutanix QuickClone

    Nutanixenablesadministratorstorapidlydeploynewvirtualmachinesbyusing

    itsQuickClonefeature.QuickClonesarewriteablesnapshotsthatbehavejust

    likestandardvDisks-administratorscanattachthemtoaVM,writedataon

    them,andevensnapshotthemfurther.Thisisusefulfordeployingnewvirtual

    desktops,creatingtestanddevelopmentcopiesofaproductiondatabaseand

    anyotherscenariorequiringcloneswithoutduplicatingthedata.Thesystem

    alsosupportsread-onlysnapshotsforbackuppurposes.

    Nutanix Thin Provisioning

    Storageforvirtualmachinesisthinlyprovisionedinthesystem.Administrators

    cansetthecapacityofavDiskbutphysicalstorageisallocatedonlywhen

    required.Administratorscanalsosetaminimumreservationparameterthat

    guaranteesthespecifiedamountofstorageforacollectionofvDisks.

    Nutanix Converged Backup

    TheConvergedBackupfeatureprovidesinstantbackupandrecoverycapabilities

    forvDisks.Severalmonthsworthofbackupscanbekeptinsidetheappliance

    withoutrequiringexternalbackupstorage.Whenrecoveryisnecessary,

    administratorscaninstantaneouslyrestoreavDisktoanyofitspastbackups.The

    appliancealsosupportsoffsitebackupsusingstandardthird-partytools.

    Ease of ManagementEase of Deployment

    NutanixCompleteClusterisaplug-and-playsolutionthatincludesallhardware

    andsoftwarenecessarytorunalargenumberofvirtualserversorvirtual

    desktops.AdministratorscansetitupandstartcreatingVMsinamatterof

    minutes.

  • KEYFEATURES

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    Next-Generation User Interface

    NutanixCommandCenterisahighlyintuitiveFlex-baseduserinterface

    thatprovidesadministratorcompletevisibilityacrosscomputeandstorage

    resourcesinthecluster.Itenablesthemtotroubleshootissuesrelatedtoa

    virtualmachineseasilybymappingeachVMtothephysicalresourcesinthe

    system.NutanixCompleteClusteralsoprovidesacommand-lineinterfacefor

    management.

    Nutanix Scale-out Converged Storage (SOCS)

    NutanixSOCSeliminatestheneedformanagingacomplexnetwork-basedstorage

    infrastructure,makingiteasytomanagevirtualenvironmentsatanyscale.

    Conformance to IT Standards

    WhileNutanixCompleteClusterenablesaconvergedarchitecture,itcontinues

    tosupportstandardtoolsandinterfacesthatITdepartmentsalreadyuse.For

    example,thenodesrunanindustry-standardhypervisor(VMwareESXi)andall

    ITprocessesandsoftwaretoolsthatworkwiththishypervisorcontinuetowork

    withNutanix.Similarly,vDisksarestandardiSCSIdevicesthatareconnected

    toVMsusingastandardiSCSIinitiatorinthehypervisor.Byleveragingsuch

    standardinterfaces,NutanixCompleteClustercanseamlesslyfitintoanexisting

    ITecosystem.

    Performance and ScalabilitySolid-State Drives

    NutanixCompleteClusterwasdesignedwithSSDsinmind.Theincludedserver-

    basedSSDsprovidehigherperformancethanSAN-basedSSDsbecausetheyavoid

    thenetworkbottleneck.Traditionalsystemshaveoftenbeenlimitedbythe

    amountofmetadatatheycankeepinacontrollerscache.InNutanixComplete

    Cluster,SSDsareusednotonlyforVMdata,butalsoforstoringSOCSmetadata

    forfastaccess.KeepingrichmetadataonSSDsenablesSOCStoprovide

    advanceddatamanagementcapabilities.Giventhescale-outarchitecture,SSD

    capacityinthesystemgrowsasmorenodesareaddedtothecluster.

  • KEYFEATURES

    13NUTANIX COMPLETE CLUSTER:ATECHNICALWHITEPAPER

    Nutanix Heat-Optimize Tiering (HOT)

    IntheNutanixcluster,avDiskcanbeallocatedamixofSSDandHDDcapacity.

    Toensurethatonlyhigh-valuedatastaysonSSDs,SOCSmovescolddatatohigh-

    capacitySATAdrivesinthebackgroundusingitsHOTfeature.

    Scalability

    NutanixCompleteClusterisdesignedtoscalefromafewnodestoalarge

    numberofnodes.Everyaspectofthesystemwasdesignedwiththescalability

    requirementsoftodaysvirtualizeddatacentersinmind.Forexample,there

    isnocentralizedmetadatamasterinthesystem.Themetadatalayeritself

    isdistributedacrossthecluster,eliminatingacommonbottleneckfoundin

    mostscale-outsystems.Also,witheverymodulerunningaSOCSController,

    thenumberofcontrollersinthesystemcanbemuchhigherthanatypical

    network-basedstoragesolutionwithonlyafewcontrollers.Suchdesign

    innovationsenablethesystemtostartsmallandscalemassively.

    High AvailabilityNutanix Cluster RAID

    NutanixCompleteClusterisahighlyavailablescale-outsystemwithnosingle

    pointoffailure.UsingNutanixClusterRAID,dataisstripedacrossdiskswithina

    nodeforhighperformanceandreplicatedacrosstheclusterforhighavailability.

    Thisprovideshighavailabilityforvirtualmachinesevenifdisksorcomplete

    nodesfail.

    Nutanix Distributed Metadata Service (Medusa)

    Nutanixsdistributedmetadataservice,Medusa,distributestheclustermetadata

    acrosstheclusterforscalabilityandreplicatesthedataonmultiplenodesfor

    faulttolerance.Theserviceishighlyavailableandcantoleratemultiplenode

    failures.Incomparison,traditionalsolutionsthatdependonafewstorage

    controllerscannottoleratemultiplefailures.

    Nutanix Instant vDisk Motion

    TheabilitytomigratealiveVMfromonehosttoanotherisaverypowerful

    featureprovidedbytheindustry-standardhypervisors.Sofar,organizations

    havebeenabletoleveragesuchlivemigrationcapabilitiesonlywithnetwork

  • KEYFEATURES

    14NUTANIX COMPLETE CLUSTER:ATECHNICALWHITEPAPER

    storage.Infact,manyorganizationswereforcedtousenetworkstorageonly

    toachievelivemigrationandhighavailability.InNutanixCompleteCluster,live

    VMmigrationissupportedevenwiththeconvergedarchitecturethatuseslocal

    storage.vDisksintheappliancearelogicalentitiesthatarefullymobile.Thisis

    enabledbyNutanixInstantvDiskMotionfeaturethatcanquicklymoveavDisk

    fromonenodetoanother,whennecessary.

    Backup and Recovery

    Theabilitytoperformoff-sitedatabackupandrecoveryiskeytoan

    organizationsdataprotectionstrategy.NutanixCompleteClusterisfully

    compatiblewiththeVMwarevStorageAPIforDataProtection(VADP),and

    providesfullyfunctionalbackupandrecoveryofvirtualmachines,through

    integrationwithVADPcompatiblebackupandrecoveryproducts.

    Disaster Recovery

    DisasterRecoveryiskeytothebusinesscontinuityneedsofanenterprise.

    NutanixCompleteClusterprovidesfailoverandfailbackcapabilitiesthrough

    integrationwithVADPcompatibleDisasterRecoveryproducts.

  • CONCLUSIO

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    ConclusionNutanixCompleteClusterisaninnovativesystemthateliminatestheneedfor

    networkstoragewithoutcompromisingtherequirementsofenterpriseIT.It

    isbuiltusinganext-generationscale-outarchitecturethathasbeenproven

    atsomeofthemostinnovativecloud-generationcompanies.WithNutanix

    CompleteCluster,organizationscanbuildacomputeandstorageinfrastructure

    forvirtualmachinesthatishighlyavailable,fast,richindatamanagement

    featuresandcangrowastheirneedsgrow.

    Executive SummaryIntroductionLimitations of Current ArchitectureThe Google Approach

    Nutanix Complete Cluster Architecture Main PillarsArchitecture OverviewNutanix Scale-Out Converged Storage Key Components

    Key FeaturesCapacity OptimizationEase of ManagementPerformance and ScalabilityHigh Availability

    Conclusion