FAQ: Vicom Data Migration Services migrations. Vicom delivers data migrations faster, with fewer...
9
1 APPLICATION NOTE FAQ: Vicom Data Migration Services As a provider of turnkey data migration services, Vicom is often asked how our approach compares with alternative methods 1 being considered by customers. Among the comparisons requested, host or server-based migration performed by in‐house IT staffs are the most common because the method is familiar and it offers perceived cost advantages. However, as the size and complexity of SANs have grown and 24x7 operations have become more prevalent, companies are turning increasingly to outsourcing and specialized tools to help minimize the disruptive impact migrations can have on business operations. In their search for new solutions, customers ask for information about migration methods, speeds, project duration, required server and system outage, and data integrity. Their questions include: • How does Vicom’s total, turnkey approach compare with in-house, host- based migrations? • What are the primary advantages of Vicom’s migration approach? • Who are your customers? • How do Vicom’s MaxSpeed and Continuous migration methods compare in: - Migration speed? - System availability? - Time to completion? • How does Vicom verify the data integrity of its migrations? Q: How does Vicom’s approach compare with in-house, host-based migrations? Vicom Turnkey Approach to Data Migrations Vicom System’s DMS (Data Migration Service) is a turnkey service in which an experienced migration specialist manages the entire data migration project, start‐to‐finish — from initial planning to server cutover. Moreover, every DMS migration is backed by a money‐back guarantee of on‐time completion. This guarantee is made possible by: • A purpose‐built, migration appliance that moves data independent of servers and storage systems, at speeds of up to 1 terabyte per hour. 1 For an extensive survey and comparison of other migration methods, see the Vicom Systems whitepaper, “New Watchwords for Networked Storage Migrations,” November 2007.
Transcript of FAQ: Vicom Data Migration Services migrations. Vicom delivers data migrations faster, with fewer...
1
APPLICATIONNOTE
FAQ: Vicom Data Migration Services
Asaproviderofturnkeydatamigrationservices,Vicomisoftenaskedhowourapproachcompareswithalternativemethods1beingconsideredbycustomers.
Amongthecomparisonsrequested,hostorserverbasedmigrationperformedbyin‐houseITstaffsarethemostcommonbecausethemethodisfamiliaranditoffersperceivedcostadvantages.However,asthesizeandcomplexityofSANshavegrownand24x7operationshavebecomemoreprevalent,companiesareturningincreasinglytooutsourcingandspecializedtoolstohelpminimizethedisruptiveimpactmigrationscanhaveonbusinessoperations.
Intheirsearchfornewsolutions,customersaskforinformationaboutmigrationmethods,speeds,projectduration,requiredserverandsystemoutage,anddataintegrity.Theirquestionsinclude:
• HowdoesVicom’stotal,turnkeyapproachcomparewithinhouse,hostbasedmigrations?
• WhataretheprimaryadvantagesofVicom’smigrationapproach?
• Whoareyourcustomers?
• HowdoVicom’sMaxSpeedandContinuousmigrationmethodscomparein:
- Migrationspeed?- Systemavailability?- Timetocompletion?
• HowdoesVicomverifythedataintegrityofitsmigrations?
Q: How does Vicom’s approach compare with in-house, host-based migrations?
VicomTurnkeyApproachtoDataMigrations
VicomSystem’sDMS(DataMigrationService)isaturnkeyserviceinwhichanexperiencedmigrationspecialistmanagestheentiredatamigrationproject,start‐to‐finish—frominitialplanningtoservercutover.Moreover,everyDMSmigrationisbackedbyamoney‐backguaranteeofon‐timecompletion.Thisguaranteeismadepossibleby:
• Apurpose‐built,migrationappliancethatmovesdataindependentofserversandstoragesystems,atspeedsofupto1terabyteperhour.
1Foranextensivesurveyandcomparisonofothermigrationmethods,seetheVicomSystemswhitepaper,“NewWatchwordsforNetworkedStorageMigrations,”November2007.
2
Theapplianceiscapableofmigratingdatawhileserversareofflineoronline.
• SANvirtualizationtechnologythatsimplifiessystemandstorageconnectionbyeliminatingincompatibilitiesandtheneedfordriverandOSupdateinstallationsonhostsystems,includinglegacysystems.
• Automateddiscoveryandmigrationmanagementwhichreducesthelaborandhumanerrorassociatedwithcomplexmigrations.
• Aprovenmigrationprocessforplanning,discovery,migrationmanagement,andverificationthathasbeendevelopedinthecourseofdeliveringofover500enterprisedatamigrations.
• Anon‐intrusiveandsecuremigrationmethod,performedwithouttheneedforsoftwareagentsorsystemmodifications,“musts”formanysecurity‐sensitivefinancialandgovernmentapplications.
• Experiencedmigrationspecialistswhooverseetheprojectfromstarttofinish.
Vicom’sprincipalobjectiveistodeliveryaproblem‐free,on‐timemigrationatanaffordableprice.WhileVicomreliesmainlyonitsSANbasedhardwareDataMigrationAppliancetomigratedatainfast,offlinemodeorcontinuous‐accessonlinemode,wealsousehost‐basedsoftwaretoolsasneededtoperformsupplementalservices,suchasLUNconsolidationandNASmigrations.Thissolution‐orientedapproachenablesVicomtohandledatamigrationsmoreeffectivelythananyotherserviceprovidersinthestorageindustry.
Figure1.VicomAppliance‐BasedOfflineandOnlineMigration
InHouse,HostBasedMigrations
Host‐basedmigrationisafrequentchoiceofITmanagers,especiallyforsmallerdatamigrations.Becauseexistingdataiscopiedorreplicatedbetweentheoldstorageplatformandanewerone,anyofseveralmethodsofdatareplicationemployingserver‐processingpowermaybeused.Typically,dataismigratedbetweenoldandnewstoragesystemsbymirroringdatavolumeswithastoragemanagementapplicationorcopyingfilesusingnativeOStools.Insomeinstances,third‐partydatamigrationapplicationsarealsoused.
3
OneoftheprincipalreasonsITmanagersselectin‐house,host‐migrationmethodsislowerout‐of‐pocketcosts,particularlywhennativeOSutilitiesareused,sinceadditionalhardwareandsoftwarepurchasesarenotrequired.Relianceonexistingutilitiesandsystemsoftwarealsoeliminatestheneedfornewapplicationqualificationandtraining.Whenused,mirroringorfile‐copymethodsalsoenablecontinuousserveraccesstothesource(old)storagewhiledataismigratedtothenew(target)storageinthebackground.Fromaprojectmanagementstandpoint,datasetsmaybemovedindividuallyandreorganizedatthesametime—agoodoptionwhenthemigrationisrelativelysimpleandsmallinscale.
Bycomparison,specializeddatamigrationsoftwareapplicationsareoftenpreferabletonativesystemutilitiesbecausededicatedtoolscanprovidebetter,moretailoredcontroloverthemigrationprocess.Whenmigrationsoftwareisconsidered,automationanddiscoveryshouldbeamongtheprincipalreasonsforitsselection.Ataminimum,thesoftwareshouldincludemechanismsforSANdiscovery,migrationplanning,andactivemigrationmanagementandcontrols.Itshouldalsobenotedthathost‐basedmigrationsoftwaretoolsaretypicallylimitedintheirrangeofplatformcompatibilitybecausetheymustbeportedtovariousoperatingsystems.WhilethesetoolsmayworkwithcurrentOSplatforms,legacysystemsoftenpresentupgradeanddriverincompatibilityissues.
Q: What are the primary advantages of Vicom’s
migration approach?
Whilehost‐basedmigrationprovidessomeadvantages,manyofthesetendtobeoffsetbyimplementationandoperatingconsiderations,especiallyasthescaleofmigrationsandnumberofserverplatformsincrease.Inaddition,althoughout‐of‐pocketexpensesofin‐househost‐basedmigrationsmayappearsmall,thecostofITresourcescanaddupquickly.Byundertakingamigrationproject,ITassumesallresponsibilityandriskforon‐timeprojectdelivery.Moreover,latemigrationdeliveriescanalsoaddsignificantlytoleasedstoragecostsandadverselyaffectbusinessoperations.Accordingtoa2005surveyofover200ITmanagersbytheEnterpriseStorageGroupandInfoStorMagazine,83percentofinternalmigrationprojectsexceedplannedstafftime,61percentrequiremoredowntimethanexpected,and54percentareoverbudget.VicomAdvantages:ExperienceandTechnology
Vicom’stechnology,automation,provenprocesses,andspecialist‐backedserviceseliminatemuchofthecomplexityandlaborassociatedwith
Server
SAN
Figure2.Host‐BasedMigration
4
migrations.Vicomdeliversdatamigrationsfaster,withfewerproblems,andzerooperatingrisk.And,withtheexceptionofcustomizedmigrations,Vicomalsoprovidesamoney‐backguaranteeforon‐timecompletionofeachofitsmigrations.
AdvantagesofVicommigrationsoverin‐house,host‐basedmethodsinclude:
• Automateddiscoveryandconfigurationverificationthateliminateslaborandhumanerrorassociatedwithmanualmigrationmanagement.
• SANvirtualizationtechnologythateliminatesSANcompatibilityissuesandtheneedforsoftwareanddriverinstallationonhostsystems,savingtimeandlabor.
• Afast,independentdata‐movingappliancethatmigratesdataatmuchhigherratesthanpossiblewithhost‐powereddatamigrations.Typically,theVicomapplianceinMaxSpeedmodemigratesdataat600GBto1TBperhourcomparedto100GBperhourorlessforhost‐poweredmigrations.
• Guaranteedfallbacktooriginalsystemoperationintheunlikelyeventthatissuesariseduringamigration.
• Provenmigrationprocessesdevelopedinthedeliveryofover500enterprisemigrations.
• Experiencedmigrationspecialistswhohavedeliveredmigrationsinabroadrangeofenvironments,configurations,andoperatingcircumstances.Thisincludeslegacy/mixedplatformandmixedfabricenvironments,clusteredservers,bootLUN,LUNconsolidation,andcontinuousavailabilityoperations.
• Aone‐stop,solution‐orientedmigrationservicethatnotonlyuseshighlyefficientVicommigrationappliancetechnology,software,andprocesses,butalsobest‐of‐breedthird‐partysoftwaretoolstosatisfyuniquemigrationrequirements.Ourrepertoireincludeshost‐basedmethodsandsoftware.WemigratebothSANandNASdata.WithVicom,youhaveacost‐effective,single‐vendormigrationproviderregardlessofconfigurationoroperatingneeds.
Example:LaborComparisonBetweenInHouseandVicomMigrations
IncomparingVicom’sapproachwithin‐housemigrationprojects,itiseasytoseewhyVicomholdsmorethana3:1advantageinlaborandtimerequired.Mostcompaniesareconfrontedwiththeneedtoperformlarge‐scaledatamigrationsonlywhenastoragetechnologyrefreshisrequired.Asaresult,mostITstaffsarerelativelyinexperiencedatdeliveringcomplexmigrations.Often,theyhaveonlybasicprocessesestablishedforplanning,coordinatingserverandstorageavailabilities,andmigratingdata.Forthesamereason,migrationtoolsandexperienceinusingthemaretheexceptionratherthantherule.Bycomparison,aVicommigrationspecialistsperformmigrationseveryweek.Provenprocessesarefollowedoneverymigration,whiletoolsandsoftwareeliminatemuchofthelaborandneedfortroubleshootingassociatedwithmanualmigrations.
5
Toshowhowthesedifferencesaffecttheimplementationandcompletionofamigrationproject,Table2comparestheestimatedlaborfora10‐terabyte/10‐server,in‐househost‐basedmigrationconfiguredforonlineoperationwiththelaborforanequivalentonlineContinuousmigrationusingaVicommigrationappliance.
Asshownbythiscomparison,thein‐house,on‐linemigrationrequiresalmostthreetimesthelaborneededforaContinousmigrationusingtheVicomappliance.Incontrast,aVicomMaxspeedofflinemigrationwouldbeabout25percentmoreefficientthantheContinuousmethod,resultingina4:1Vicomadvantage.(Note:thecomparisondoesnotincludetimespentinreplicatingdatawhileonline,whichwillberoughlythesameforhost‐basedandVicommethods.)
Amongthesevenindividualmigrationstepsshown,Vicomholdsalaboradvantageof2:1to40:1.And,whileVicomtechnologymakesabigdifference,ourexperienceshowsthatoneofthebiggesttime‐saversistheVicommigrationplanningprocess,whichisbuiltoninformationacquiredfromVicomtoolsanddocumentation.
Q: Who are your customers?
VicommigrationcustomersrunthegamutfromFortune1000tosmallandmediumenterprisesacrossarangeofindustries.Throughdirectservicesandservicepartnerships,Vicomhassuccessfullydeliveredover500datamigrationsandmovedoverfivepetabytesofdataindiverseenterpriseenvironments.Selectedcustomersarelistedbelow.ReferencesareavailableuponrequestfromVicomSystems.
Avaya Goody’sClothing ScientificLearningBloomberg Heinz SiemensBlueCross HealthFirst SiriusSatelliteCaterpillarTractor Intelsat SouthernCompanyComcast MCGHealth StateFarmInsuranceDCMA(U.S.Gov’t) Pepsico TexasLegislativeCouncil
Table 2. Labor Comparison for Host-Based vs. Vicom Appliance-Based Migration
6
DeutscheBank Prudential TorayPlasticsDialAmerica ReedBusiness TimkenEsurance RoperSt.FrancisHealth UnileverFruitoftheLoom RoyalCaribbean WellsFargo
Q: How do Vicom’s MaxSpeed and Continuous Migration methods compare in:
• Migration speed?
• System availability?
• Time to completion? Vicom’sMaxSpeedmigrationsareperformedduringplannedoutageperiodswhenserversmaybetakenoffline.Duringtheseperiods,themigrationappliancereplicatesdatafromsourcetonewstoragesystematmaximumavailableI/Obandwidths.However,undersomecircumstancessuchase‐commerce,operatingrequirementsmayseverelyrestricttheperiodinwhichhostserverscanremainoffline.Intheseinstances,itmaybemoreeffectivetouseaContinuousmigrationmethodinwhichdataismigratedinthebackgroundwhilethehostserversremainonline.Figure3illustrateshowthesetwomethodscompareinserveroutagewindowsandtimerequiredtoperformthemigrations.
Figure3.MaxSpeedvs.ContinuousMigration
7
Table1belowfurtherillustateshowthetwomethodsdifferinmigrationspeed,serveravailability,andmigrationcompletiontimes.
Timeandspeed‐wise,MaxSpeedmigrationsaremuchfasterthanContinuousalternatives,especiallyasthenumberofserversincreases.ThisisduetothespeedadvantageofVicom’smigrationapplianceandefficiencyoftheMaxSpeedmigrationmethod.Forthetypicalmid‐sizemigrationof5‐30terabytesand10‐20servers,MaxSpeedmigrationscanbecompletedabout4timesfasterthanContinuousmigrations.
InlargeSANstoragemigrations,wheretherearebusiness‐criticalandnon‐businesscriticalavailabilityrequirements,VicomusesbothMaxSpeedandContinuousmigrationmethods.Typically,Maxspeedmigrationisusedtomigratethemajorityofdataquicklyandefficiently,whileContinuousmigrationisreservedforbusiness‐criticalapplications.Thiscombinedapproachproducesacost‐effectiveresult,whilealsosatisfyinghigh‐availabilityoperatingneeds.
Q: How Does Vicom Ensure Migration Data Integrity? Toensuremigrationdataintegritywhilealsomeetingoperatingconstraints,VicomSystemsemploysamulti‐leveldataverificationmethodthathasbeenusedinover500enterprisemigrationswitha100‐percentsuccessrate.Infact,inmigratingoverfivepetabytesofdata,notasinglebyteofdatahaseverbeenlostorcorrupted.Toachievethis,Vicomemploysacombinationofdeviceandsystem‐levelverificationthatincludes:• SAN‐level,error‐correctionlogicbuiltintoVicom’smigrationappliance• SAN‐levelerror‐logging• LUNintegritychecks• Filesystemandapplicationchecks
Table1.MaxSpeedvs.ContinuousMigrationSpeeds
8
SANlevelErrorCorrection
TheVicommigrationapplianceisdesignedforextremelyreliableSANdatareplicationatFibreChannelspeed.Inreplicatingdata,allsourcestoragedataremainsintactduringandaftermigration,providingafail‐safefallbackalternativeintheunlikelyeventofadatamigrationproblem.Throughembeddedhardwaredesign,allmigrateddataissubjectedtoerrorcheckingandsingleanddouble‐biterrorsaredetectedonthefly.Replicationalsorequiresthatdatamustbeverifiedbeforeitcanbewrittentothenewsystem.Error‐correctionandreplicationbytheVicomappliance,combinedwithhighlyreliableSCSI/FCprotocol,producestheequivalentofdirectRAID1mirroringbetweenthesourceandnewstoragesystem.Ineffect,theVicomapplianceactsasadedicatedRAIDcontrollerthatcreatesamirroredcopyofthesourcedata—asimplerandmorereliablemethodthanhost‐basedcopymethodsofdatamigration.
SANlevelExceptionLogging
TheVicomappliancemonitorstheentiredatamigrationandlogsanyexceptionsreportedduringtheoperation.Whenreported,abnormallevelsofexceptionhandlingmayindicatepotentialdataintegrityproblems.Vicomstandardprocedurescallformigrationspecialiststoreviewexceptionlogs,and,ifproblemsareidentified,torepeatthemigrationfortheproblematicLUN.LUNIntegrityChecks
Followingmigration,thefirstandlastdatablocksofeachnewLUNarecomparedwithdatablocksinthesourceLUN.FileSystemandApplicationChecks
Thefinalverificationstepfollowingmigrationconsistsof100‐percentfilesystemconsistencycheck(FSCK)ofdatavolumesand100‐percentapplicationlaunchtest.Ingeneral,customerITstaffshavepreferredtoperformthissetoftestsasameansoffirst‐handmigrationverification,aidedbytheVicommigrationspecialistasrequired.
Figure4.DataIntegrityChecks
9
Asmentionedatthebeginningofthisnote,Vicomhasmigratedoverfivepetabyteswithoutaninstanceoflossorcorruptionofasinglebyteofdata.Thisincludesthemigrationofover100,000LUNs.Basedonactualperformance,webelievetheefficacyofbothVicommigrationtechnologyanddata
www.vicom.com
Copyright 2009, Vicom Systems, Inc. All rights reserved. Vicom Systems, Vicom DMS, and MaxSpeed are trademarks of Vicom Systems, Inc. Other company and product names mentioned herein are trademarks of their respective companies. December 2008. V010809.
