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ISM Book Exercise
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Chapter1
1.AhospitalusesanapplicationthatstorespatientXraydataintheformoflargebinaryobjectsinanOracledatabase.TheapplicationishostedonaUNIXserver,andthehospitalstaffaccessestheXrayrecordsthroughaGigabitEthernetbackbone.AnEMCCLARiiONstoragearrayprovidesstoragetotheUNIXserver,whichhas6TBofusablecapacity.Explainthecoreelementsofthedatacenter.Whatarethetypicalchallengesthestoragemanagementteammayfaceinmeetingtheserviceleveldemandsofthehospitalstaff?Describehowthevalueofthispatientdatamightchangeovertime.
Solution/Hint:
Coreelementsofthedatacenter:ApplicationDatabaseoracle
ServerandoperatingsystemUNIXserver
NetworkLAN,SAN
StoragearrayEMCCLARiiONstoragearrayChallenges:
LongtermpreservationHighcost
Howpatientdatamightchangeovertime:
Forfirst60days,thepatientdataisaccessedfrequently
Afterthattherequirementofthepatientdataisveryless,soitcouldbemovedtoCAS.
2.Anengineeringdesigndepartmentofalargecompanymaintainsover600,000engineeringdrawingsthatitsdesigner'saccessandreuseintheircurrentprojects,modifyingorupdatingthemasrequired.Thedesignteamwantsinstantaccesstothedrawingsforitscurrentprojects,butiscurrentlyconstrainedbyan
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infrastructurethatisnotabletoscaletomeettheresponsetimerequirements.Theteamhasclassifiedthedrawingsas"mostfrequentlyaccessed,""frequentlyaccessed,""occasionallyaccessed,"and"archive."
SuggestandprovidethedetailsforastrategyforthedesigndepartmentthatoptimizesthestorageinfrastructurebyusingILM.
Explainhowyouwilluse"tieredstorage"basedonaccessfrequency.
Detailthehardwareandsoftwarecomponentsyouwillneedtoimplementyourstrategy.
Researchproductsandsolutionscurrentlyavailabletomeetthesolutionyouareproposing.
Solution/Hint:
ClassifythedataaccordingtoaccessfrequencyorvalueandusetieredstoragethatoptimizestheinfrastructurecostandperformancebyusingILM.
Storagerequirementcanbeclassifyas:
frequentlyuseddatashouldbeplacedinhighendstoragearrayoccasionallyaccessedshouldbeinlowendstoragearrayandarchiveddatainspecializedCASsystem
Hardwareandsoftwarecomponentsneeded:
HighendandMidrangestoragearrayContentaddressedstorage(CAS)
FCSAN,LANServer
Software:
ILMtool
Researchonfollowingproductsandsolutions(www.emc.com)
StoragearraysCLARiiON/Symmetrix
CASCentera
FCSANSwitches/DirectorsILMstrategy
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3.Themarketingdepartmentatamidsizefirmisexpanding.Newhiresarebeingaddedtothedepartmentandtheyaregivennetworkaccesstothedepartment'sfiles.IThasgivenmarketinganetworkeddriveontheLAN,butitkeepsreachingcapacityeverythirdweek.Currentcapacityis500MB(andgrowing),withhundredsoffiles.UsersarecomplainingaboutLANresponsetimesandcapacity.AstheITmanager,whatcouldyourecommendtoimprovethesituation?Solution/Hint:
NAS
4.Alargecompanyisconsideringastorageinfrastructureonethatisscalableandprovideshighavailability.Moreimportantly,thecompanyalsoneedsperformanceforitsmissioncriticalapplications.Whichstoragetopologywouldyourecommend(SAN,NAS,IPSAN)andwhy?
Solution/Hint:
SANisarecommendedsolution.
BecauseSANhashighscalabilityandavailability(usingdirectororswitch).
Chapter2
WhatarethebenefitsofusingmultipleHBAsonahost?Solution/Hint:
Highavailability
Anapplicationspecifiesarequirementof200GBtohostadatabaseandotherfiles.Italsospecifiesthatthestorageenvironmentshouldsupport5,000IOPSduringitspeakprocessingcycle.Thedisksavailableforconfigurationprovide66GBofusablecapacity,andthemanufacturerspecifiesthattheycansupportamaximumof140IOPS.Theapplicationisresponsetimesensitiveanddiskutilizationbeyond60percentwillnotmeettheresponsetimerequirementsoftheapplication.Computeandexplainthetheoreticalbasisfortheminimumnumberofdisksthatshouldbeconfiguredtomeettherequirementsoftheapplication.Solution/Hint:
Numberofdiskrequired=max(sizerequirement,IOPSrequirements)Tomeetthesizerequirement=200GB/66GB=4disksTomeettheIOPSrequirement=5000IOPS/(140x0.6IOPS)=60disks=max(4,60)=60disks
Whichcomponentsconstitutethediskservicetime?WhichcomponentcontributesthelargestpercentageofthediskservicetimeinarandomI/O
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operation?Solution/Hint:
seektime,rotationallatencyandtransferrate
seektime
Whydoformatteddiskshavelesscapacitythanunformatteddisks?Solution/Hint:
Inordertomakestoragedevicefunctional,itneedtobeformatted.CommontypesofdriveformatsareFAT32,NTFSandext2.Ineachoftheformattingschemes,aportionofthestoragespaceisallocatedtoconfiguredfilesystemtoenablecatalogingdataonthediskdrive.
TheaverageI/Osizeofanapplicationis64KB.Thefollowingspecificationsareavailablefromthediskmanufacturer:averageseektime=5ms,7,200rpm,transferrate=40MB/s.DeterminethemaximumIOPSthatcouldbeperformedwiththediskforthisapplication.Takingthiscaseasanexample,explaintherelationshipbetweendiskutilizationandIOPS.Solution/Hint:
Thediskservicetime(Rs)isakeymeasureofdiskperformance;andRsalongwithdiskutilizationrate(U)determinestheI/Oresponsetimeforapplications.
Thetotaldiskservicetime(Rs)isthesumofseektime(E),rotationallatency(L),andtheinternaltransfertime(X):Rs=E+L+X
EisdeterminedbasedontherandomnessoftheI/Orequest.LandXaremeasuresprovidedbydiskvendorsastechnicalspecificationsofthedisk.Averageseektimeof5msinarandomI/Oenvironment,orE=5msDiskrotationspeedof7,200rpmfromwhichrotationallatency(L)canbedetermined,whichisonehalfofthetimetakenforafullrotationor
L=(0.5/7,200rpmexpressedinms)40MB/sinternaldatatransferrate,fromwhichtheinternaltransfertime(X)isderivedbasedontheblocksizeoftheI/O.Withablocksizeof64KB,X=64KB/40MBConsequentlyRs=5ms+(0.5/7,200)+64KB/40MB=5+4.167+1.6=10.767ms
Themaximumno.ofI/OsservicedpersecondorIOPS=1/RSInotherwords,foranI/Owithablocksizeof64KBand
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Rs=10.767ms,themaximumIOPSwillbe1/(10.767*10"3)=92.876IOPS
6.ConsideradiskI/OsysteminwhichanI/Orequestarrivesattherateof80IOPS.Thediskservicetimeis6ms.
a.Computethefollowing:UtilizationofI/Ocontroller,Totalresponsetime,Averagequeuesize,andTotaltimespentbyarequestinaqueue.
b.Computetheprecedingparameteriftheservicetimeishalved.Solution/Hint:
Arrivalrate(a)=80IOPS,consequently,thearrivaltimeRa=1/a=1/80=12.5msRs=6ms(given)
1.Utilization(U)=Rs/Ra
=6/12.5=0.48or48%
2.Responsetime(R)=Rs/(1U)
=6/(10.48)=11.5ms
3.Averagequeuesize=U/(1U)
=(0.48)2/(l0.48)=0.44
4.Timespentbyarequestinaqueue=UxR,orthetotalresponsetimeservicetime=0.48x11.5=5.52ms
Now,ifcontrollerpowerisdoubled,ortheservicetimeishalved;consequentlyRs=3msinthisscenario.
1.Utilization(U)=Rs/Ra=3/12.5=0.24or24%
2.Responsetime(R)=Rs/(1U)=3/(10.24)=3.9ms
3.Averagequeuesize=U2/(lU)=(0.24)2/(10.24)=0.08
4.Timespentbyarequestinaqueue=0.24x3.9=0.936ms
7.RefertoQuestion6andplotagraphshowingtheresponsetimeandutilization,considering20percent,40percent,60percent,80percent,and100percentutilizationoftheI/Ocontroller.Describetheconclusionthatcouldbederivedfromthegraph.Solution/Hint:
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1.
Utilization=20%=0.2
Responsetime
7.5ms
2.
Itili/ation=40
%=0.4
Responsetime=
10ms
3.
Utilization=60
%=0.6
Responsetime
15ms
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4.
1tiliAition=80
%=0.8
Responsetime
30ms
5.
LUili/ation=100
%=1
Responsetime=
infinity
70i
^,,,,,,,,
102030405060708090
Utilization(%)
Chapter3
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1.WhyisRAID1notasubstituteforabackup?Solution/Hint:
RAID1providesprotectionagainstdiskfailureandnotasolutionfordatarecoveryduetodisaster.
2.WhyisRAIDnotanoptionfordataprotectionandhighavailability?Solution/Hint:
Itdoesnotprovideanydataprotection.
3.ExplaintheprocessofdatarecoveryincaseofadrivefailureinRAID5.Solution/Hint:
ItperformsXORoperationbetweenremainingdisksandregeneratelostdata.
4.WhatarethebenefitsofusingRAID3inabackupapplication?Solution/Hint:
BackupapplicationperformslargesequentialI/OsandRAID3givesbestresultincaseoflargesequentialI/Ooperation.
5.DiscusstheimpactofrandomandsequentialI/OindifferentRAIDconfigurations.
Solution/Hint:
RAID
Random
Sequential
3
Goodforrandomreadsandpoortofairforsmallrandomwrites.
verygoodforsequentialreadsandgoodforlarge,sequentialwrites.
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5
Verygoodforrandomreads.Fairforrandomwrite.Slowerduetoparityoverhead.
Goodforsequentialreads.Fairtogoodforsequentialwrites.
1/0
Verygoodforrandomwrite.
Poortofairforsequentialwrites
6.A10Krpmdriveisratedtoperform130IOPS,anda15Krpmdriveisratedtoperform180IOPSforanapplication.Theread/writeratiois3:1.ComputetheRAIDadjustedIOPSforthe10Kand15KdrivesforRAID1,RAID5,andRAID6.
Solution/Hint:QuestionInvalid
7.Anapplicationhas1,000heavyusersatapeakof2IOPSeachand2,000typicalusersatapeakof1IOPSeach,witharead/writeratioof2:1.Itisestimatedthattheapplicationalsoexperiencesanoverheadof20percentforotherworkloads.CalculatetheIOPSrequirementforRAID1,RAID3,RAID5,andRAID6.
Solution/Hint:
1000heavyusersatapeakof2IOPSeach=2000IOPS2000typicalusersatapeakof1IOPSeach=2000IOPS
Assumemaximumconcurrency90%
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[(2000+2000)*0.9]=3600hostbasedIOPSfor3000usersduringpeak
activityperiod
read/writeratio2:1
8.ForQuestion7,computethenumberofdrivesrequiredtosupporttheapplicationindifferentRAIDenvironmentsif10Krpmdriveswitharatingof130IOPSperdrivewereused.
Solution/Hint:
NumberofdrivesrequiredtosupporttheapplicationindifferentRAIDenvironments,if10krpmdriveswitharatingof130IOPSperdrive
ForRAID1ForRAID3ForRAID5ForRAID6
3600*2/3+(2*1/3*3600)3600*2/3+(4*1/3*3600)3600*2/3+(4*1/3*3600)3600*2/3+(6*1/3*3600)
4800IOPS7200IOPS7200IOPS9600IOPS
ForRAID1=4800/130=37drivesForRAID3=7200/130=55drivesForRAID5=7200/130=55drivesForRAID6=9600/130=74drives
Chapter4
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1.ConsiderascenarioinwhichanI/Orequestfromtrack1isfollowedbyanI/Orequestfromtrack2onasectorthatis180degreesawayfromthefirstrequest.Athirdrequestisfromasectorontrack3,whichisadjacenttothesectoronwhichthefirstrequestismade.Discusstheadvantagesanddisadvantagesofusingthecommandqueuingalgorithminthisscenario.
Solution/Hint:
Inthisscenario,commandqueuingproviderotationallatencyoptimizationwhererequestfromtrack3isservicedbeforerequest2toavoidonerotationtiming.Assumeifrequest3isfromthesametrack1inthatcasecommandqueuingprovidesseektimeoptimizationandimprovesdiskperformance.
2.WhichapplicationbenefitsthemostbybypassingthewritecacheandWhy?
Solution/Hint:
ApplicationwithverylargesizeI/Owrites.
3.AnOracledatabaseusesablocksizeof4KforitsI/Ooperation.Theapplicationthatusesthisdatabaseprimarilyperformsasequentialreadoperation.Suggestandexplaintheappropriatevaluesforthefollowingcacheparameters:cachepagesize,cacheallocation(readversuswrite),prefetchtype,andwriteasidecache.
Solution/Hint:
Cachepagesize:4K
Cacheallocation(readversuswrite):morereadcache
prefetchtype:fixedprefetch
Writeasidecache:Largevalue
Chapter5
1.DASprovidesaneconomicallyviablealternativetootherstoragenetworkingsolutions.Justifythisstatement.
Solution/Hint:
Setuprequiresarelativelylowerinitialinvestment
Setupismanagedusinghostbasedtools,suchasthehostOS,whichmakes
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storagemanagementtaskseasyforsmallandmediumenterprises.Requiresfewermanagementtasks,andlesshardwareandsoftwareelementstosetupandoperate.
2.HowistheprioritysequenceestablishedinawideSCSIenvironment?Solution/Hint:
InawideSCSI,thedeviceIDsfrom8to15havethehighestpriority,buttheentiresequenceofwideSCSIIDshaslowerprioritythannarrowSCSIIDs.Therefore,theoverallprioritysequenceforawideSCSIis7,6,5,4,3,2,1,0,15,14,13,12,11,10,9,and8.
3.WhyisSCSIperformancesuperiortothatofIDE/ATA?Explainthereasonsfromanarchitecturalperspective.
Solution/Hint:
SCSIoffersimprovedperformanceandexpandabilityandcompatibilityoptions,makingitsuitableforhighendcomputers.Numberofdevicessupportedis16
SCSIarchitecturederivesitsbasefromtheclientserverrelationshipSCSIinitiator,oraclient,sendsarequesttoaSCSItarget,oraserver.ThetargetperformsthetasksrequestedandsendstheoutputtotheinitiatorWhenadeviceisinitialized,SCSIallowsforautomaticassignmentofdeviceIDsonthebus,whichpreventstwoormoredevicesusingthesameSCSIIDs.
4.ResearchbladeserverarchitectureanddiscussthelimitationsofDASforthisarchitecture.
Solution/Hint:DASLimitations
DASdoesnotscalewell,hasalimitednumberofports
AlimitedbandwidthinDASrestrictstheavailableI/Oprocessingcapability.
ThedistancelimitationsassociatedwithDAS
Inabilitytosharetheresources,unusedresourcescannotbeeasilyreallocated,resultinginislandsofoverutilizedandunderutilizedstoragepools.
5.WhatwouldyouconsiderwhilechoosingserialorparalleldatatransferinaDASimplementation?Explainyouranswerandjustifyyourchoice.
Solution/Hint:
DistanceandspeedarethekeyfactorsSerialdatatransfercanovercomethedistancelimitationsParalleldatatransfercanovercometheseedlimitationsParalleldatatransferissuitableforInternalDAS
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SerialdatatransferissuitableforExternalDAS
6.Ifthreeharddiskdrivesareconnectedinadaisychainandcommunicateover
SCSI,explainhowtheCPUwillperformI/Ooperationswithaparticulardevice.Solution/Hint:
Eachdiskwillbeidentifiedbycn|tn|dnnumber
Asthethreedisksareconnectedinadaisychaincnandtnnumberwillbethesameforallthedisks
SCSIcommands/responsewillbeusedforthecommunication
Chapter6
1.Whatiszoning?Discussascenario,
(i)wheresoftzoningispreferredoverhardzoning.
(ii)wherehardzoningispreferredoversoftzoning.Solution/Hint:
ZoningisanFCswitchfunctionthatenablesnodeswithinthefabrictobelogicallysegmentedintogroupsthatcancommunicatewitheachother.Azoneconsistsofselecteddevices,suchashostbusadapters(HBAs)andstoragedevices,inthefabric.Devicesassignedtoonezonecancommunicatewithotherdevicesinthesamezone,butnotwithdevicesinzonesofwhichtheyarenotmembers.Thiszoningpracticeprovidesafast,efficient,andreliablemeansofcontrollingtheHBAdiscovery/loginprocess.Withoutzoning,theHBAwillattempttologintoallportsonthefabricduringdiscoveryandduringtheHBA'sresponsetoastatechangenotification.Withzoning,thetimeandFibreChannelbandwidthrequiredtoprocessdiscoveryandthestatechangenotificationareminimized.
(i)SoftzoningisalsocalledWWNzoninganditispreferredwhenuserneedflexibilitytophysicallymoveattachednodesbetweenswitchportsrecabletheSAN,thatmaytakeplaceduringswitchmaintenanceandrepairwithoutreconfiguringthezoneinformation.ThisispossiblebecausetheWWNisstatictothenodeport.
(ii)Hardzoningisalsocalledportzoning,itisconvenientwhenthereisaneedforhardwarereplacementasWWNisuniquelyassociatedwithahardware.
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2.DescribetheprocessofassigningFCaddresstoanodewhenloggingintothenetworkforthefirsttime.
Solution/Hint::
Tologontothefabric,anodesendsaFLOGIframewiththeWorldWideNodeName(WWNN)andWorldWidePortName(WWPN)parameterstotheloginserviceatthewellknownFCaddressFFFFFE.Inturn,theswitchacceptstheloginandreturnsanAccept(ACC)framewiththeassignedFCaddressforthedevice.ImmediatelyaftertheFLOGI,theN_portregistersitselfwiththelocalnameserverontheswitch,indicatingitsWWNN,WWPN,andassignedFCaddress.
3.Seventeenswitches,with16portseach,areconnectedinameshtopology.Howmanyportsareavailableforhostandstorageconnectivityifyoucreateahighavailabilitysolution?
Solution/Hint:
Totalports=17*16=272
NumberofISL136
EachISLconsumes2ports
numberofportsavailableforhosts
4.DiscusstheadvantageofFCSWoverFCAL.
Solution/Hint::
Unlikealoopconfiguration,aFibreChannelswitchedfabric(FCSW)networkprovidesinterconnecteddevices,dedicatedbandwidth,andscalability.Theadditionorremovalofadeviceinaswitchedfabricisminimallydisruptive;itdoesnotaffecttheongoingtrafficbetweenotherdevices(ascomparedtoFCAL).InFCSW,nodesdonotsharealoop;instead,dataistransferredthroughadedicatedpathbetweenthenodes.FCuses24bitfibrechanneladdressingschemeforconnectivitywhichcansupportupto15milliondevices(FCALuses8bitaddressingwhichcansupportupto127devicesonaloop)
5.HowflowcontrolworksinFCnetwork.Solution/Hint::
Flowcontrolisusedtodefineandregulatethepaceofflowofdataframesbetweensenderandreceiverduringdatatransmission.FCtechnologyusestwoflowcontrolmechanisms:buffertobuffercredit(BBCredit)andendtoendcredit(EECredit).
BB_Credit:Theprocessisasfollows
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1.Atlogin,thetransmitterandthereceiverexchangeparametersandestablishtheBBCreditvalue.
2.Thetransmitter'scountinitializestotheBBCreditvalue.
3.If(BBCredit>0),transmittersendsaframe,anddecrementsthecountpertransmittedframe.
4.AnRRDY(ReceiverReady)issentfromthereceivingporttothetransmittingportforeveryavailablebufferonthereceivingside.
5.Thetransmitterincrementsthecountby1foreachRRDYitreceivesfromthereceiver.Thetransmittingportmaintainsacountoffreereceiverbuffers.
5.Uponalinkreset,theBBCreditvalueresetstothevaluenegotiateduponlogin.
EE_Credit
Thefunctionofendtoendcredit,knownasEECredit,issimilartothatofBB_Credit.(TheEECreditmechanismisusedfortheflowcontrolforclass1andclass2trafficonly).
6.Whyisclass3servicemostpreferredforFCcommunication?Solution/Hint:
NondedicatedconnectionBBcredit
HighbandwidthutilizationSupportformultiplexing
Chapter7
1.ListandexplaintheconsiderationsforcapacitydesignforbothCPUandstorageinaNASenvironment.
Solution/Hint:
ThescalabilityofcapacitycanbeaconstraintinanintegratedNAS.However,thegatewayNAScanscalefortherequiredconnectivityandstorage.GatewayNASsharesCPUloadwithSANworkloadandmayfaceconstraintonCPUutilization.Typically,CPUcapacityisnotthemajorbottleneckfactorinaNASsystem,butotherconsiderationssuchasmemoryrequirement,numberofnetworkports,filesystem,IOPSrequirements,alongwithstoragecapacityrequirementsareimportantfactor.
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2.SANisconfiguredforbackuptoadiskenvironment,andthestorageconfigurationhasadditionalcapacityavailable.CanyouhaveaNASgatewayconfigurationusethisSAN?DiscusstheimplicationsofsharingthebackuptodiskSANenvironmentwithNAS.
Solution/Hint:
AstheadditionalcapacityisavailablegatewayNAScanbeimplemented.ButduringthebackupwindowitwillhaveconsiderableperformanceimpactonNetworkandhenceNAS.
3.ExplainhowtheperformanceofNAScanbeaffectediftheTCPwindowsizeatthesenderandthereceiverarenotsynchronized.
Solution/Hint:
ThiswillaffecttheNASperformanceasthismayleadtoretransmissionofdata,lowerbandwidthutilization,performancedegradationofthenetwork,intermittentconnectivity,anddatalinkerrors.
4.ResearchtheuseofbabyjumboframesandhowitaffectsNASperformance.Solution/Hint:
CommonEthernetJumboframesizeis9000BytesBabyjumboframessizeis2.5KBBytes
5.ResearchthefilesharingfeaturesoftheNFSprotocol.
Hint:Researchquestion(refertoNFSprotocolsectioninthebook)
6.ANASimplementationconfiguredjumboframesontheNAShead,with9,000asitsMTU.However,theimplementersdidnotseeanyperformanceimprovementandactuallyexperiencedperformancedegradation.Whatcouldbethecause?Researchtheendtoendjumboframesupportrequirementsinanetwork.
Solution/Hint:
Jumboframesareusedattheendpoint(NASHead)withMTUof9000CheckiftheintermediatenetworkusesadifferentMTUsize(e.g.1500).ThiscancausetheroutertodroppacketswhichthenhavetoretransmitattheTCPlayer.
PacketsarethenfragmentedandhavetoreassembletoaccommodatethedifferentMTUsizes.Thisdegradesnetworkperformance.
7.AcmeCorporationistryingtodecidebetweenanintegratedoragatewayNASsolution.TheexistingSANatAcmewillprovidecapacityandscalability.TheIT
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departmentisconsideringaNASsolutionfortheTrainingdepartmentatAcmefortrainingvideos.Thevideoswouldonlybeusedbythetrainingdepartmentforevaluationofinstructors.PickaNASsolutionandexplainthereasonsforyourchoice.Solution/Hint:
ExistingSAN;sothechoicewillbegatewayNASCheckifSANhasadditionalcapacityavailable.
Chapter8
1.HowdoesiSCSIhandletheprocessofauthentication?Researchtheavailableoptions.
Solution/Hint::
CHAP(Challengehandshakeauthenticationprotocol)
2.ListsomeofthedatastorageapplicationsthatcouldbenefitfromanIPSANsolution.
Solution/Hint:
ExtendingreachofexistingSANDisasterrecoverysolutionsRemoteofficeapplications
3.WhatarethemajorperformanceconsiderationsforFCIP?Solution/Hint:
Refersection8.2.2FCIPPerformanceandsecurity
4.ResearchthemultipathingsoftwareavailableforaniSCSIenvironment.WriteatechnicalnoteonthefeaturesandfunctionalityofEMCPowerPathsupportforiSCSI.
Hint:Researchwork
5.ResearchtheiSCSIcapabilitiesinaNASdevice;provideusecaseexamples.Hint:Researchwork
6.Acompanyisconsideringimplementingstorage.Theydonothaveacurrentstorageinfrastructuretouse,buttheyhaveanetworkthatgivesthemgoodperformance.DiscusswhethernativeorbridgediSCSIshouldbeusedandexplainyourrecommendation.
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Solution/Hint:
NativeiSCSIimplementationdoesn'tinvolveanyFCcomponentswhile
BridgediSCSIimplementationinvolvesFCcomponents
Asthecompanydoesn'thavestorageinfrastructureandthenetworktheyhave
givesthemagoodperformancenativeiSCSIshouldbedeployed.
iSCSIenabledStorageisonlyneededifnativeiSCSIistobeimplementedin
thiscase.
7.TheIPbandwidthprovidedforFCIPconnectivityseemstobeconstrained.DiscussitsimplicationsiftheSANsthataremergedarefairlylarge,with500portsoneachside,andtheSANsatbothendsareconstantlyreconfigured.
Solution/Hint:
AsbandwidthisinsufficientIPnetworkwillbecomethebottleneckAsthefabricsonbothsidesarefairlylargeandareconstantlyreconfiguredanydisruptionintheIPnetworkwillleadtoinstabilitiesinunifiedfabric.Theseincludeasegmentedfabric,excessiveRSCNs,andhosttimeouts.
ThesolutioncanbetosegregateFCIPtrafficintoaseparatevirtualfabric,toprovideadditionalstability,
8.ComparedtoastandardIPframe,whatpercentageofreductioncanberealizedinprotocoloverheadinaniSCSIconfiguredtousejumboframeswithanMTUvalueof9,000?
Solution/Hint:
iSCSIPDUsize=1460bytes(containpayloadandadditionalheadersegment)Jumboframesizeof9000MTUoutofwhichpayloadis8960JumboFramesallowsasignificantamountofincreasedpayloadtobedeliveredineachiSCSIPDU.
9.WhyshouldanMTUvalueofatleast2,500beconfiguredinabridgediSCSIenvironment?
Solution/Hint:
FCsupportsframesizeof2148byte
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Chapter9
1.ExplainhowaCASsolutionfitsintotheILMstrategy.Solution/Hint:
AccordingtoILMstrategyvalueofinformationchangesoveritslifecycle,whencreatedvalueofinformationisveryhighanditisfrequentlyaccessedandchanged,henceplacedinahighperformancecostlystorage.Withthetimeitsvaluedropsanditbecomesfixedcontentwhichisrarelyaccessed,butstillholdsplaceincostlystoragespace.Forthecostoptimizationlessaccesseddatashouldbemovedtoarchivedandleavethecostlyspaceforhighvaluedata.CASisasolutionforarchiveddata,whichnotonlyprovidecostbenefitbutalsoprovidefasteraccessandreliablestoragetofixedcontent.
2.ToaccessdatainaSAN,ahostusesaphysicaladdressknownasalogicalblockaddress(LBA).AhostusingaCASdevicedoesnotuse(orneed)aphysicaladdress.Why?
Solution/Hint:
Unlikefilelevelandblockleveldataaccessthatusefilenamesandthephysicallocationofdataforstorageandretrieval,CASstoresdataanditsattributesasanobject.Thestoredobjectisassignedagloballyuniqueaddressknownasacontentaddresswhichisderivedfromtheactualbinaryrepresentationofstoreddata.
3.TheITdepartmentofadepartmentalstoreusestapetoarchivedata.Explain45majorpointsyoucouldprovidetopersuadetheITdepartmenttomovetoaCASsolution.HowwouldyoursuggestionsimpacttheITdepartment?
Solution/Hint:
GuaranteedContentAuthenticityandIntegrity:Datacannotbemanipulated
oncestored,meetregulatoryandbusinesscompliance.
SingleInstanceStorage:Simplifiesstorageresourcemanagement,especially
whenhandlinglargeamountoffixedcontent.
FasterDataRetrieval:Comparedtotape
Technologyindependence:Aslongastheapplicationserverisabletomaptheoriginalcontentaddressthedataremainsaccessible.
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Betterdataprotectionanddisposition:AllfixedcontentisstoredinCASonceandisbackedupwithaprotectionscheme.
Chapter10
1.WhatdoVLANsvirtualize?DiscussVLANimplementationasavirtualizationtechnology.
Solution/Hint:
VLANstandforvirtualLANwhichhassameattributesasofphysicalLAN,butallowshoststobegroupedtogethereveniftheyarenotlocatedonthesamenetworkswitch.Withtheuseofnetworkreconfigurationsoftware,portsonthelayer2switchcanbelogicallygroupedtogether,formingaseparate,VirtualLocalAreaNetwork.VLANshelptosimplifynetworkadministration.PortsinaVLANcanbelimitedtoonlythenumberneededforaparticularnetwork.ThisallowsunusedportstobeusedinotherVLANs.Throughsoftwarecommands,additionalportscanbeaddedtoanexistingVLANiffurtherexpansionisneeded.IfamachineneedstobemovedtoadifferentIPnetwork,theportisreassignedtoadifferentVLANandthereisnoneedforthephysicalmovementofcables.
3.Howcanablocklevelvirtualizationimplementationbeusedasadatamigrationtool?Explainhowdatamigrationwillbeaccomplishedanddiscusstheadvantagesofusingthismethodforstorage.Comparethismethodtotraditionalmigrationmethods.
Solution/Hint:
Conventionallydatamigrationneedsphysicalremappingofserverstonewstoragelocationwhichresultedinapplicationdowntimeandphysicalchanges.Inavirtualizedenvironmentvirtualvolumesareassignedtothehostoutofphysicalpoolofstoragecapacity.Datamigrationisachievedthroughthesevirtualvolumes.Tomoveavirtualvolume,virtualizationsoftwareperformsaredirectionofLOfromonephysicallocationtoanother.DespitethefactthattheLOisphysicallyredirectedtoanewlocationbythevirtualizationsoftware,theaddressofthevirtualvolumepresentedtothehostneverchanges.Thisisaccomplishedthroughvirtualaddressing.Thisallowstheprocesstobetransparentandnondisruptivetothehost.Additionally,sincethecopyingandremappingisdonebythevirtualizationsystem,nohostcyclearerequired,freeingserverstobededicatedtotheirproperapplicationcentricfunction.
Chapter11
1.Anetworkrouterhasafailurerateof0.02percentper1,000hours.Whatisthe
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MTBFofthatcomponent?
Solution/Hint:
MTBFofnetworkrouter=1/Failurerate
=100*1000/0.02=50,00,000hrs
2.TheITdepartmentofabankpromisescustomeraccesstothebankratetablebetween9:00a.m.and4:00p.m.fromMondaytoFriday.Itupdatesthetableeverydayat8:00a.m.withafeedfromthemainframesystem.Theupdateprocesstakes35minutestocomplete.OnThursday,duetoadatabasecorruption,theratetablecouldnotbeupdated,andat9:05a.m.,itwasestablishedthatthetablehaderrors.Arerunoftheupdatewasdone,andthetablewasrecreatedat9:45a.m.Verificationwasrunfor15minutes,andtheratetablebecameavailabletothebankbranches.Whatwastheavailabilityoftheratetablefortheweekinwhichthisincidenttookplace,assumingtherewerenootherissues?
Solution/Hint:
Availability=totaluptime/totalscheduledtimeTotalscheduledtime=7hrs*5=35hrs
Totaluptime=34hrs(asonThursdayratetablewasmadeavailableat10:00aminsteadof9:00am)
Therefore,availabilityoftheratetablefortheweek=34/35
3.'Availabilityisexpressedintermsof9s."Explaintherelevanceoftheuseof9sforavailability,usingexamples.
Solution/Hint:
Uptimeperyearisbasedontheexacttimelinessrequirementsofthe
service,thiscalculationleadstothenumberof"9s"representationforavailabilitymetrics.
Forexample,aservicethatissaidtobe"five9savailable"isavailablefor99.999percentofthescheduledtimeinayear(24x7x365).
Uptime(%)Downtime(%)DowntimeperDowntimeper
YearWeek
99.9990.0015.25minutes6sec
4.Provideexamplesofplannedandunplanneddowntimeinthecontextofdatacenteroperations.
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Solution/Hint:
Examplesofplanneddowntime:installation/integration/maintenanceofnewhardware,softwareupgradesorpatches,takingbackups,application
anddatarestores,facilityoperations(renovationandconstruction),refresh/migrationoftestingenvironmenttotheproductiondata
Examplesofunplanneddowntime:failurecausedbydatabasecorruption,componentfailure,humanerrors
5.HowdoesclusteringhelptominimizeRTO?Solution/Hint:
RTOof1hour:Clusterproductionserverswithcontrollerbaseddiskmirroring.
RTOofafewseconds:Clusterproductionserverswithbidirectionalmirroring,enablingtheapplicationstorunatbothsitessimultaneously.
6.Howisthechoiceofarecoverysitestrategy(coldandhot)determinedinrelationtoRTOandRPO?
Solution/Hint:
RTOandRPOsmallhotsite
RTOandRPOlargecoldsite
7.Assumethestorageconfigurationdesignshowninthefollowingfigure:
Performthesinglepointoffailureanalysisforthisconfigurationandprovideanalternateconfigurationthateliminatesallsinglepointsoffailure.
Solution/Hint:
Singlepointoffailure:host,switch,storagearray,HBA,arrayportandpath
AlternateconfigurationasshownbelowtoavoidSPF
Host
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StorageArray
t.iuslhimiISkrhrh
RedundantFCSwitcherI
Chapter12
1.Amanufacturingcorporationusestapeasitsprimarybackupstoragemediathroughouttheorganization:
FullbackupsareperformedeverySunday.
IncrementalbackupsareperformedMondaythroughSaturday.
Theenvironmentcontainsmanybackupservers,backingupdifferentgroupsofservers.
Theemailanddatabaseapplicationshavetobeshutdownduringthebackupprocess.
Duetothedecentralizedbackupenvironment,recoverabilityisoftencompromised.Therearetoomanytapesthatneedtobemountedtoperformafullrecoverincaseofacompletefailure.Thetimeneededtorecoveristoolengthy.Thecompanywouldliketodeployaneasytomanagebackupenvironment.Theywanttoreducetheamountoftimetheemailanddatabaseapplicationsareunavailable,andreducethenumberoftapesrequiredtofullyrecoveraserverincaseoffailure.
Proposeabackupandrecoverysolutiontoaddressthecompany'sneeds.Justifyhowyoursolutionensuresthattheirrequirementswillbemet.
Solution/Hint:
Thesolutionshouldhavethefollowingelements:
Centralizedbackupserver
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Backupagentstoavoidtherequirementforcriticalapplicationstobeshutdownduringthebackupprocess.
Useofacumulativebackuppolicyinsteadofincrementalbackups,reducingtheamountoftaperequiredforafullrestore.
2.TherearelimitedbackupdevicesinafilesharingNASenvironment.Suggestasuitablebackupimplementationthatwillminimizethenetworktraffic,avoidanycongestion,andatthesametimenotimpacttheproductionoperations.Justifyyouranswer.
Solution/Hint:
ThisisachievedbytheintroductionofNDMP,topromotedatatransportbetweenNASandbackupdevices.Duetoitsflexibilityitisnolongernecessarytotransportthedatathroughthebackupserver.Dataissentfromthefilerdirectlytothebackupdevice,whilemetadataissenttothebackupserverfortrackingpurposes.Thissolutionmeetsthestrategicneedtocentrallymanageandcontroldistributeddata,whileminimizingnetworktraffic.NDMP3wayisusefulwhentherearelimitedbackupdevicesintheenvironment,enablingtheNASdevicecontrollingthebackupdevicetoshareitwithotherNASdevices,byreceivingbackupdataviaNDMP.
3.Discussthesecurityconcernsinbackupenvironment.
Solution/Hint:
Majorsecurityconcerninbackupenvironmentisspoofingbackupserver,backupclientorbackupnodeidentitybyunauthorizedhost,togainaccesstobackupdata.Anotherconcernisbackuptapebeinglost,stolen,ormisplaced,especiallyifthetapescontainhighlyconfidentialinformation.Backuptotapeapplicationsarealsovulnerabletosecurityimplicationsiftheydonotencryptdatawhilebackingup.Lastlybackupdatashreddingshouldalsoconsider,byperformingsafetapedataerasureoroverwritingiftheynolongerrequired.
4.Whatarethevariousbusiness/technicalconsiderationsforimplementingabackupsolution,andhowdotheseconsiderationsimpactthebackupsolution/
implementation?
Solution/Hint:
>RTOandRPOaretheprimaryconsiderationsinselectingandimplementinga
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>specificbackupstrategy.
>Retentionperiod
>Backupmediatype
>Backupgranularity
>Timeforperformingbackupandavailablebackupwindow
>Locationandtimeoftherestoreoperation
>filecharacteristics(location,size,andnumberoffiles)anddatacompression
5.Whatisthepurposeofperformingoperationbackup,disasterrecovery,andarchiving?
Solution/Hint:
Operationbackup:TorestoredataintheeventofdatalossorlogicalcorruptionsDisasterrecovery:Forrestoringdataatanalternatesitewhentheprimarysiteis
incapacitatedduetoadisaster.Archiving:Forlongtermdataretention(regulatorycomplianceorbusiness
requirement)
6.Listandexplaintheconsiderationsinusingtapeasthebackuptechnology.Whatarethechallengesinthisenvironment?
Solution/Hint:
Advantages:
Offsitedatacopy
LowerinitialcostChallenges:
Reliability
Restoreperformance(mount,loadtoready,rewind,dismounttimes)
SequentialAccess
HVACcontrolledenvironment
Shipping/handlingchallenges
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7.Describethebenefitsofusing"virtualtapelibrary"over"physicaltapes."
Features
Tape
VirtualTape
OffsiteCapabilities
Yes
Yes
Reliability
Noinherentprotectionmethods
RAID,spare
Performance
Subjecttomechanicaloperations,loadtimes
Fastersinglestream
Use
Backuponly
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Backuponly
Chapter13
1.Whatistheimportanceofrecoverabilityandconsistencyinlocalreplication?Solution/Hint:
Recoverabilityenablesrestorationofdatafromthereplicastotheproductionvolumesintheeventofdatalossordatacorruption.RecoverabilitymustprovideminimalRPOandRTOforresumingbusinessoperationsontheproductionvolumes.
Consistencyensurestherestartabilityfromdata.Businessoperationcannotresumefrominconsistentdata.
2.Describetheusesofalocalreplicainvariousbusinessoperations.
Solution/Hint:
AlternatesourceforbackupFastrecovery
DecisionsupportactivitiessuchasreportingTestingplatformDatamigration
3.Whataretheconsiderationsforperformingbackupfromalocalreplica?
Solution/Hint:
ThereplicashouldbeconsistentPITcopyofthesourceReplicashouldnotbeupdatedwhenthebackupwindowisopen
4.Whatisthedifferencebetweenarestoreoperationandaresynchronizationoperationwithlocalreplicas?Explainwithexamples.
Solution/Hint:
Restoreoperation
Sourceissynchronizedwiththetargetdata
Forexample,ifsourcecontainsadatabasewherealogicaldatacorruptionoccurs,thedatacanberecoveredbyattachingthelatestPITreplicaofthesourceandmakingincrementalrestoreoperation.Resynchronizationoperation
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Targetissynchronizedwiththesourcedata
Forexample,aftertargetisdetachedfromthesource,bothsourceandtargetdataareupdatedbythehost.Aftersometimethetargetneedstobesynchronizedwiththesourcedata.Forthat,targetisagainattachedtothesourceandincrementalresynchronizationisperformed.
5.A300GBdatabaseneedstwolocalreplicasforreportingandbackup.Thereareconstraintsinprovisioningfullcapacityforthereplicas.Ithasbeendeterminedthatthedatabasehasbeenconfiguredon15disks,andthedailyrateofchangeinthedatabaseisapproximately25percent.Youneedtoconfiguretwopointer
basedreplicasforthedatabase.Describehowmuchcapacityyouwouldallocateforthesereplicasandhowmanysavevolumesyouwouldconfigure.
Solution/Hint:
75GBofsavevolumesarerequired
space/capacityisallocated,sinceitispointerbasedreplica
6.ForthesamedatabasedescribedinQuestion5,discusstheadvantagesofconfiguringfullvolumemirroringiftherearenoconstraintsoncapacity.
Solution/Hint:
Infullvolumemirroring,thesourceneednotbeup/healthyforrecovery.
7.AnadministratorconfiguressixsnapshotsofaLUNandcreateseightclonesofthesameLUN.Theadministratorthencreatesfoursnapshotsforeachclonethatwascreated.Howmanyusablereplicasarenowavailable?
Solution/Hint:
Usablereplicas=6+8+32=46
8.RefertoQuestion5.Havingcreatedthetworeplicasforbackupandreportingpurposes,assumeyouarerequiredtoautomatetheprocessesofbackupandreportingfromthereplicasbyusingascript.Developascriptinapseudolanguage(youcanusethestandardTimeFindercommandsfortheoperationsyouneedtoperform)thatwillfullyautomatebackupandreporting.Yourscriptshouldperformalltypesofvalidationsateachstep(e.g.,validatingwhetherasynchronizationprocessiscompleteoravolumemountissuccessfullydone).
Solution/Hint:
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Createaflowchartinsimplelanguage.
Chapter14
1.Anorganizationisplanningadatacentermigration.Theycanonlyaffordamaximumoftwohoursdowntimetocompletethemigration.Explainhowremotereplicationtechnologycanbeusedtomeetthedowntimerequirements.Whywilltheothermethodsnotmeetthisrequirement?
Solution/Hint:
SANbasedremotereplicationtechnologycanbeusedtoavoidthedowntimeasitprovidenondisruptivedatamigration.Conventionalmethodsneeddowntimetomigratedatafromonelocationtoother.
2.ExplaintheRPOthatcanbeachievedwithsynchronous,asynchronous,anddiskbufferedremotereplication.
Solution/Hint:
RPOthatcanbeachievedwithsynchronousoftheorderofSecondsRPOthatcanbeachievedwithasynchronousoftheorderofMinutesRPOthatcanbeachievedwithDiskbufferedremotereplicationofthe
orderofhours
3.Discusstheeffectsofabunkerfailureinathreesitereplicationforthefollowingimplementation:
Multihopsynchronous+diskbuffered
Multihopsynchronous+asynchronous
Multitarget
Solution/Hint:
Multihopsynchronous+diskbuffered
Sameassynchronous+asynchronous
Multihopsynchronous+asynchronous
Ifthereisadisasteratthebunkersiteorifthereisanetworklinkfailure
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betweenthesourceandbunkersites,thesourcesitewillcontinuetooperateasnormalbutwithoutanyremotereplication.Thissituationisverysimilartotwositereplicationwhenafailure/disasteroccursatthetargetsite.Theupdatestotheremotesitecannotoccurduetothefailureinthebunkersite.Hence,thedataattheremotesitekeepsfallingbehind;buttheadvantagehereisthatifthesourcefailsaswellduringthistime,operationscanberesumedattheremotesite.RPOattheremotesitedependsonthetimedifferencebetweenthebunkersitefailureandsourcesitefailure.
Multitarget
Afailureofthebunkerortheremotesiteisnotconsideredadisasterbecausenormaloperationscancontinueatthesourcesitewhileremotedisasterrecoveryprotectionisstillavailablewiththesitethathasnotfailed.Anetworklinkfailuretoeitherthebunkersite(target1)orthe
remotesite(target2)enablesbusinessoperationstocontinueuninterruptedatthesourcesitewhileremotedisasterrecoveryprotectionisstillavailablewiththesitethatcanbereached.
4.Discusstheeffectsofasourcefailureinathreesitereplicationforthefollowingimplementation,andtheavailablerecoveryoptions:
Multihopsynchronous+diskbuffered
Multihopsynchronous+asynchronous
Multitarget
Solution/Hint:
Multihopsynchronous+diskbuffered
Sameassynchronous+asynchronous
Multihopsynchronous+asynchronous
Ifthereisadisasteratthesource,operationsarefailedovertothebunkersitewithzeroornearzerodataloss.Butunlikethesynchronoustwositesituation,thereisstillremoteprotectionatthethirdsite.TheRPObetweenthebunkerandthirdsitecouldbeontheorderofminutes.
Multitarget
Ifasourcesitedisasteroccurs,BCoperationscanbestartedwiththebunker(target1)ortheremotesite(target2).Undernormalcircumstances,thedataatthebunkersiteisthemorerecentandupto
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date.Hence,operationsareresumedwiththebunkersitedata.Insomecircumstances,thedataontheremotesiteismorecurrentthanthedataonthebunkersiteforexample,ifthenetworklinksbetweenthesourceandbunkersiteshasfailed.Inthiscase,theworkloadwouldcontinueatthesourcesitewithjusttheasynchronousreplicationtotheremotesite.Ifthesynchronouslinksaredownlongenough,thenthedataattheremotesitewouldbemorecurrentthanthedataatthebunkersite.Ifasourcesitedisasteroccursatthistime,thedataontheremotesiteshouldbeusedtorecover.Thenetworklinksbetweenthebunkerandremotesitesareactivatedinthissituationtoperformincrementalsynchronization.TheRPOisnearzeroifthebunkersitedataisused,anditisinminutesiftheremotesitedataisused.
5.Ahostgenerates8,000I/OsatpeakutilizationwithanaverageI/Osizeof32KB.Theresponsetimeiscurrentlymeasuredatanaverageof12msduringpeakutilizations.WhensynchronousreplicationisimplementedwithaFibreChannellinktoaremotesite,whatistheresponsetimeexperiencedbythehostifthenetworklatencyis6msperI/O?
Solution/Hint:
Actualresponsetime=12+(6*4)+(32*1024/8000)=40.096Where12ms=currentresponsetime6msperI/O=latency32*1024/8000=datatransfertime
Chapter15
1.Researchthefollowingsecurityprotocolsandexplainhowtheyareused:Hint:Researchwork
2.Astoragearraydialsasupportcenterautomaticallywheneveranerrorisdetected.Thevendor'srepresentativeatthesupportcentercanlogontotheserviceprocessorofthestoragearraythroughtheInternettoperformdiagnosticsandrepair.Discusstheimpactofthisfeatureinasecurestorageenvironmentandprovidesecuritymethodsthatcanbeimplementedtomitigateanymaliciousattacksthroughthisgateway.
Solution/Hint:
Modificationattacks
Inamodificationattack,theunauthorizeduserattemptstomodifyinformationformaliciouspurposes.Amodificationattackcantargetdataatrestordataintransit.Theseattacksposeathreattodataintegrity.DenialofService
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DenialofService(DoS)attacksdeniestheuseofresourcestolegitimateusers.Theseattacksgenerallydonotinvolveaccesstoormodificationofinformationonthecomputersystem.Instead,theyposeathreattodataavailability.TheintentionalfloodingofanetworkorwebsitetopreventlegitimateaccesstoauthorizedusersisoneexampleofaDoSattack.
Eavesdropping
Whensomeoneoverhearsaconversation,theunauthorizedaccessiscalledEavesdropping.Snooping
Thisreferstoaccessinganotheruser'sdatainanunauthorizedway.Ingeneral,snoopingandeavesdroppingaresynonymous.Managementaccess
Managementaccess,whethermonitoring,provisioning,ormanagingstorageresources,isassociatedwitheverydevicewithinthestoragenetwork.MostmanagementsoftwaresupportssomeformofCLI,systemmanagementconsoleorawebbasedinterface.SControllingadministrativeaccess
Controllingadministrativeaccesstostorageaimstosafeguardagainstthethreatsofanattackerspoofinganadministrator'sidentityorelevatinganotheruser'sidentityandprivilegestogainadministrativeaccess.Bothofthesethreatsaffecttheintegrityofdataanddevices.Toprotectagainstthesethreats,administrativeaccessregulationandvariousauditingtechniquesareusedtoenforceaccountability.fProtectingthemanagementinfrastructure
Protectingthemanagementnetworkinfrastructureisalsonecessary.Controlstoprotectthemanagementnetwork
infrastructureincludeencryptingmanagementtraffic,enforcingmanagementaccesscontrols,andapplyingIPnetworksecuritybestpractices.ThesebestpracticesincludetheuseofIProutersandEthernetswitchestorestricttraffictocertaindevicesandmanagementprotocols.
3.DevelopachecklistforauditingthesecurityofastorageenvironmentwithSAN,NAS,andiSCSIimplementations.Explainhowyouwillperformtheaudit.Assumethatyoudiscoveratleastfivesecurityloopholesduringtheauditprocess.Listthemandprovidecontrolmechanismsthatshouldbeimplementedtoeliminatethem.
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Solution/Hint:
SAN,NAS,iSCSI
Servers(Production,management,backup,thirdparty,NAS)
oWhatdataorobjectwasaccessed/attemptedtoaccess?
oWhatactionwasperformed?
oWhenwasexecuted?
oWhoauthorizedandperformedtheaction?
oNFS/CIFSaccess(sharedfiles)
Fabric/IPnetwork
oPhysicalandlogicalaccess
Switches
oPhysicalandlogicalaccessoZoning
Storage
oWhichvolumewasaccessed/attemptedtoaccess?
oWhatactionwasperformed?
oWhenwasexecuted?
oWhoauthorizedandperformedtheaction?
oLUNmasking
oProvisioning
oUpgrade/replacement
oHandlingofphysicalmedia
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Process
Collectlogandcorrelate
Analyzeaccessandchangecontrol
oProductionandDRsiteoBackupandreplicationoThirdpartyservice
Checkalertingmechanism
Checksecuritycontrols
oPhysical
oAdministrative
oTechnological
Identifysecuritygap
Documentationandrecommendation
Fivesecurityloopholes
1.Authenticationallowsmultiplelogin
2.Nofirewall
3.Noauthenticationattheswitchlevel
4.Noencryptionforinflightdata
5.Poorphysicalsecurityatthedatacenter
Control
1.Restrictioninnumberofloginattempt,twopartpassword
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2.Implementfirewalltoblockinappropriateordangeroustraffic
3.Authenticateusers/administratorsofFCswitchesusingRADIUS(RemoteAuthenticationDialInUserService),DHCHAP(DiffieHellmanChallengeHandshakeAuthenticationProtocol),etc.
4.Encryptingthetrafficintransit
5.Increasesecuritymanpowerandimplementbiometricsecurity
Chapter16
1.DownloadEMCControlCentersimulatorandtheaccompanyinglabguidefromhttp://education.emc.com/ismbookandexecutethestepsdetailedinthelabguide.
Labexercise
2.Aperformanceproblemhasbeenreportedonadatabase.Monitoringconfirmsthatat12:00a.m.,aproblemsurfaced,andaccesstothedatabaseisseverelyaffecteduntil3:00p.m.everyday.Thistimeslotiscriticalforbusinessoperationsandaninvestigationhasbeenlaunched.Areportingprocessthatstartsat12:00p.m.contendsfordatabaseresourcesandconstrainstheenvironment.Whatmonitoringandmanagementprocedures,tools,andalertswouldyouestablishtoensureaccessibility,capacity,performance,andsecurityinthisenvironment?Hints:
Monitoring:
Settingupmonitoringandreportingforaccessibility,capacity,performanceandsecurityonproductionandreplicationdataMonitoringandmanagementtoolssuchasECCPerformancemanagerneedtobedeploytogatherallperformancestatisticsdata(historicaldata)Performanceanalysisperformanceconstraintisbecauseoftheresource
Management:
Requirement:Databaseneedtobereplicateforreportingprocess
SBasedonrequirementandinfrastructurechosenreplication
softwareneedtobedeploySProvisionstoragecapacityforreplicationfConfiguretheenvironmentforaccessingreplicateddata(need
configurationathost,networkandstorage)
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SConfigureadequatecapacitybasedonpolicyondataretention
andchangeSConfiguresecurityforreplicateddata
3.ResearchSMISandwriteatechnicalpaperondifferentvendorimplementationsofstoragemanagementsolutionsthatcomplywithSMIS.
Researchwork
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