Sun Microsystems Virtual Tape Library User manual

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Virtual Tape Library
VTL User Guide
Part No. 96267
May 2008, Revision G

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96267 • G iii
Revision History
Short Name Part # Revision Date Comments
VTL User Guide 96267 Nov 2006 Base document supplied by the
vendor.
A Jan 2007 Major revision.
B Mar 2007 Published. EC 131376.
C Aug 2007 Major revision.
D Nov 2007 Minor revision.
E Feb 2008 Major revision to cover VTL Plus 2.0
F Mar 2008 Major revision to the commandline
appendix
G May 2008 Revised for VTL Plus 2.0 Update 1.

iv VTL User Guide • May 2008 G • 96267

96267 • G v
Contents
About this book xi
1. Introduction:VTLappliancesandenterprisedata‐protection 1
Features 2
AdvantagesofVTLtapevirtualization 4
Shorterruntimesandreduceddependencyonbackupwindows 4
Shorterruntimesfornon‐sequentialbackupjobs 5
Improvedreliability 5
Betterutilizationoftapesubsystems 5
Improvedutilizationofbackupmedia 6
Larger,moreflexiblelibraries 6
CompatibilitywithACSLSmanagementsoftware 6
Truetapevirtualizationwithdynamicallyallocateddiskspace 7
KeyVTLfeaturesandoptions 8
NDMPmigration 8
VTLhigh‐availabilityoption 9
AutomatedTapeCaching 12
Virtualtapereplication 12
VTLSecureTapeencryptionoption 14

vi VTL User Guide • May 2008 G • 96267
2. UnderstandingVTLZoning 15
Zoningforstandard‐availabilitysystems 15
Zoningforhigh‐availabilitysystems 16
3. UsingtheVTLconsole 19
RunningtheVTLconsoleapplication 20
Populatingtheconsole 20
UnderstandingtheVTLconsoleinterface 22
VirtualTapeLibrarySystem 24
SANClients 25
Reports 25
PhysicalResources 26
4. VTLoperations 27
Managingnetworkconnectivity 27
Managingvirtuallibraries 33
Configuringphysicallibrariesanddevices 34
Configuringandprovisioningvirtuallibraries 39
Creatingvirtualtapes 56
Connectingvirtuallibrarieswithstorageclients 64
ControllingVTLvirtuallibrarieswithACSLS 70
BackinguptheVTLsystemconfiguration 75
Recoveringtheserverconfiguration 79
ProtectingVTLmetadata 79
Administeringuseracountsandpasswords 82
Virtualtapedrivecompression 84
Managingtapes 86
Locatingvirtualtapes 86
Replicatingtapes 86

96267 • G Contents vii
Copyingtapes 104
Movingtapesbetweenvirtualandphysicallibraries 107
Managingtapecaching 120
Creatingandviewingreports 123
Encryptingandshreddingdata 127
WorkingwiththeEventLog 135
UsingtheAttentionRequiredtab 138
ManagingVTLservers 140
5. InstallingtheVTLconsole143
6. Recoveryfollowingasystemfailure 147
Failback 147
Resumingbackupsfollowingafailover/failback 157
7. Configuringemailalerts 159
8. UpdatingVTLsoftware 165
A. VTLcommandlinereference 169
Usingthecommandlineutility 169
Commands 169
Commonarguments 170
Login/logouttotheVTLServer 171
LogintotheVTLServer 171
LogoutfromtheVTLServer 172
Virtualdevices/Clients 172
Getvirtualdevicelist 172
GetClientvirtualdevicelist 173
Addclient 174
Deleteclient 174

viii VTL User Guide • May 2008 G • 96267
Getclientproperties 175
Assignvirtualdevice 175
Unassignvirtualdevice 176
Createvirtualdevice 177
Deletevirtualdevice 177
Getsupportedvirtuallibraries 178
Getsupportedvirtualdrives 179
Createvirtualtapelibrary 179
Addvirtualtapedrive 181
Createstandalonetapedrive 182
Createvirtualtape 183
Movevirtualtape 184
Tapecopy 186
Settapeduplication 186
Settapeproperties 187
Automatedtapecaching 189
Settapecaching 189
Syncphysicaltapes 191
Migratevirtualtapes 192
Reclaimdiskspace 193
Renewcache 193
Systemconfiguration 194
Addalicensekeycode 194
Removealicensekeycode 195
GetVTLinfo 195
Import/Export 196
Importtape 196
Exportvirtualtape 197

96267 • G Contents ix
Getimport/exportjobstatus 198
Resumeimport/exportjobs 199
Deleteimport/exportjobs 200
Suspendimport/exportjobs 200
Cancelimport/exportjobs 200
Replication 201
Createareplica 201
Promoteareplica 203
Removereplication 203
Suspendreplication 204
Resumereplication 205
Setreplicationproperties 205
Getreplicationproperties 206
Getreplicationstatus 207
Startreplication 207
Stopreplication 208
Physicaldevices 208
Inventoryphysicaltapelibrary 208
Getphysicaltapelist 209
Movephysicaltape 209
Ejectphysicaltape 210
AssignphysicalresourcetoVTL 211
UnassignphysicalresourcefromVTL 211
Getphysicaldeviceinformation 212
Rescanphysicaldevices 213
Importdisk 213
PreparephysicaldeviceforVTLserver 214
Reports 215

xVTL User Guide • May 2008 G • 96267
Serverthroughputreport 215
SCSIchannelthroughputreport 216
Devicethroughputreport 217
Physicalresourcesconfigurationreport 218
Diskusagereport 218
Physicalresourcesallocationreport 219
Specificphysicalresourceallocationreport 219
FibreChanneladapterconfigurationreport 220
Replicationstatusreport 220
Virtuallibraryinformationreport 221
Virtualtapeinformationreport 222
Createjobreport 223
EventLog 224
GetEventLog 224
Technicalsupport 225
GetX‐Ray 225
Getattentionrequiredinformation 226
B. Requiredports 227
C. Troubleshooting 229
Problemsduringconsoleoperations 229
Problemsaffectingphysicalresources 232
Problemswithvirtualresources 233
Problemsduringimport/exportoperations 237
TakinganX‐rayfortechnicalsupport 239
D. SNMPtraps 243
E. ILOMcommandreference 275

96267 • G xi
Aboutthisbook
Thisbookintroducestapevirtualizationandguidesyouthroughtheadministration
ofSunStorageTekVirtualTapeLibrary(VTL)solutions,includingVTLPlus2.0and
VTLValuesystems.Itstartswithahigh‐levelexplanationofVTLtechnology,
commondeploymentarchitectures,andspecialfeatures.Itthenprovidesdetailed
instructionsforcarryingoutthetaskscommontoVTLadministrationaccordingto
SunVTLbestpractices,including:
■SANzoning
■usingtheVTLConsolegraphicaluserinterface(GUI)andinstallingcopieson
managementstations
■administeringlocalareanetwork(LAN)connections
■designing,creating,andmanagingvirtuallibrariesandvirtualtapes
■usingspecialfeatureslikeautomatictapecaching,automatictapearchiving,and
tapereplication
■usingencryptionanddatacompressionfeaturestobestadvantage
■handlingfailbackafterahigh‐availabilitysystemhasfailedover
■reporting
■configuringandusingemailnotifications
Finally,appendicesprovideadditionalinformationthat,whilenotessentialtoa
normalinstallation,mayproveusefulinspecialcircumstances.
Thedocumentistask‐oriented,organizedaroundtheworkyouhavetodoratherthan
aroundthefeaturesorcomponentsoftheproduct.Eachchapterandsectionbegins
withalistofthetasksitcontains.Tasksarepresentedinorder,andthestepsineach
processarenumbered,inthesequenceinwhichtheyaretobeperformed.
Conditionalsteps(stepsthatyouperformonlyinspecifiedcircumstances)begin
withthecondition(“IfA...”)andendwiththecorrespondingaction(“...doB”);if
theconditiondoesnotapply,yousimplyskipthestep.Eachtaskendswitha
referencetothenexttaskinthesequence:
Nexttask:“Installing...”onpage 3.

xii VTL User Guide • May 2008 G • 96267
Whenthesetupprocessbranches,thetaskendswithconditionalalternatives:
Nexttask:
■Ifthecustomerdoesnotplantorunthemanagementconsolefromahoston
thelocalareanetwork(LAN),pressSkip,andgotothenexttask.
■Otherwise,carryouttheprocedure“ConfiguringtheEthernetLAN”on
page 57.
Whenyouhavefinishedasequenceoftasks,thisisclearlynoted:
Stop here.
Tominimizethetimeyouspendswitchingbetweenpublicationsorbetweenmajor
sectionsofthedocument,wehavemadeanefforttoavoidcrossreferencesto
externalinformationwhereverpossible.Ifyouneedtohaveafigure,atable,ora
procedure,itshouldalwaysbe,atworst,onaneighboringpage.
Takingadvantageofthisbook’shypertextfeatures
Ifyouchoosetoviewthisbookonline,ratherthaninprintedform,youcanjump
quicklytoanypartofthebookbyclickingonthecorrespondingentryunderthe
BookmarkstabontheleftsideoftheAdobeAcrobatinterface.Inaddition,clicking
onentriesinthetableofcontents,crossreferences,orreferencestosubsequenttasks
willtakeyoudirectlytotheindicatedpartofthedocument.Youcanthenusethe
backarrowontheAdobeAcrobatReadertoreturn,ifdesired,tothepointyouleft.
Inaddition,clickingonmostUniformResourceLocators(URLs)andonmost
referencestoonlineresourceswillopenyourdefaultwebbrowsertothe
correspondingwebpage,sothatyoucan,ifnecessary,obtainarequireddownload
immediately(beaware,however,URLstospecificpageschangefrequentlyandmay
notalwaysbeaccurate).

96267 • G About this book xiii
Understandingtheconventionsusedinthisbook
Thetablebelowillustratestheconventionsthatrepresentliteralandvariablevalues,
commands,andpropertynamesinthisbook.
Obtainingthelatestinformationandsupportingresources
TheSunStorageTekSupportportal<www.support.storagetek.com>provides
linkstothelatestdocumentation,softwareupdates,andlicensingresourcesforVTL
Plussolutions.Alwayschecktheportalforupdatestothisdocumentbefore
proceeding.DocumentsdistributedonCDROMmaynotreflectthelatestchangesto
VTLhardware,software,andservices.
Commentingonthisbook
Sunwelcomesyourcommentsandsuggestionsforimprovingthisbook.Contactus
at[email protected]. Pleaseincludethetitle,partnumber,issuedate,andrevision:
VTL User Guide,partnumber96267(May2008Revision G).
Convention Meaning Examples
AaBbCc123 Fixed‐widthtextisusedforliteralvalues,
includingnamesofcommands,files,
directories,literalcomputerinputs/outputs,
andUniformResourceLocators(URLs)
Edityour.loginfile.
Use ls -a tolistfiles.
% You have mail.
AaBbCc123
AaBbCc123
Obliquetextisusedforvariablesthatstand
forrealnamesorvaluesandforbooktitles.
Todeleteafile,type:
rmfilename.
ABCD Bold,san‐seriftextindicatescalloutsin
illustrations.
Click Submit (Abelow).
1. Numberedparagraphsindicatestepsina
processthatshouldbeexecutedinsequential
order.
■Bulletedparagraphsindicatelistsof
alternativesorcomponents.
[VTL_Plus]#acommandlineprompt

xiv VTL User Guide • May 2008 G • 96267

96267 • G 1
CHAPTER 1
Introduction:VTLappliancesand
enterprisedata‐protection
SunStorageTekVirtualTapeLibrary(VTL)technologymakesthebenefitsofdisk‐to‐
disk‐to‐tapearchitectureavailabletocomplexbackupenvironmentsthatcannot
readilyaccommodatethedisruptionsandadministrativeburdensthatoften
accompanymajorchangestoinformation‐managementenvironmentsandprocesses.
VTLsolutionsmakediskmediaavailabletoapplicationsthatareconfiguredtowork
withtape.VTLsoftwarepresentsyourexistingtape‐centricbackuparchitecturewith
whatappeartobefamiliartapelibraries,drives,anddatacartridgeswhilemanaging
thecomplexitiesoftheimplementation—diskarrays,RAIDgroups,andlogical
volumes—internally.
Suchtransparencyisabsolutelycriticalwhenbackupisjustoneaspectofan
enterprise‐widebusiness‐continuityplan.Whenlegacysystemsandmultiple,
interdependentapplications,procedures,policies,and/orserviceprovidersare
involved,evenmodestchangestoabackuparchitecturecanhaveunforeseen,far‐
reachingconsequences.
Theadvantagesthatdisk‐to‐diskbackuphastoofferarenolesscriticalincomplex
environments.Heavyworkloads,tightschedules,andmultipledependenciesoften
makebackupwindowsverytightornon‐existent.Jobsthatfailtocompletecannot,
inmostcases,beretried.Tape‐basedbackupsystemsperformwellwhenhandling
bigjobs,likefullbackupsoflargefilesandfilesystemsthatcanstreamlarge
amountsofsequentialdata.Butmuchofthecurrentbackupworkloadconsistsof
intermittent,essentiallyrandomI/O—incrementals,fullbackupsofheterogeneous
smallserversandworkstations,andsmallfiles(suchasthoseassociatedwithemail
systems).Tapedrivesperformpoorlyundertheseconditions.Butdisk‐basedstorage
isideallyplacedtohandlethistypeofI/O.
Theremainderofthischapterprovides:
■abriefsummaryofVTL“Features”onpage 2
■adetaileddiscussionofthe“A d va n t a g e s ofVTLtapevirtualization”onpage 4
■amorein‐depthlookatselected,“KeyVTLfeaturesandoptions”onpage 8.

Features
2VTL User Guide • May 2008 G • 96267
Features
TheSunStorageTekVTLsolutionhasthefollowingfeatures:
■Emulationofmostwidelyusedtapelibraries,drives,andmediatypes,including
thelatestSunStorageTekT10000‐seriesdrivesandmedia
■Dynamicallocationofdiskcapacity
VTLsoftwarecanallocatediskspacetovirtualtapesin5‐GBincrements,upto
thefull,ratedcapacityoftheemulatedmedia.Thisminimizeswastedspace,
providesnaturalloadbalancing,andoptimizestheperformanceofthediskarray.
■AutoArchivefeature
TheAutoArchiveoptionwritesdatatophysicaltapewheneverabackup
applicationorutilitymovesavirtualtapefromavirtuallibrarytoan
import/exportslot.Thephysicaltapelibrarymustsupportbarcodes:theVTL
softwarehastofindamatchingbarcodeinthephysicallibraryinordertoexport
avirtualtapetoaphysicalcartridge.
■ReplicationoftapestolocalandremoteVTLsystems
VTLsoftwaresupportsmanualcopyingandbothevent‐andpolicy‐driven
automaticreplicationmethods.
■AutomatedTapeCachingoption
Withtheoptionaltape‐cachingfeature,VTLsoftwarecanautomaticallysavea
singlevirtualvolumewithasinglebarcodeintwophysicalforms,oneondisk
andoneonphysicaltape.Thetape‐cachingfeaturemanagesretentionand
migrationofthephysicalimages,underthecontrolofuser‐specifiedpoliciesand
schedules.Thisletsuserskeepspaceinthediskcachefreefornewbackupsets
whileretainingthetapeimagesofoldervirtualvolumes.Whenavirtualvolume
nolongerresidesinthediskcache,apointerinthecacheseamlesslyredirects
requeststothetapeimage.
■Highavailabilityoption
Anoptional,high‐availabilityconfigurationprovidesintelligentfailover,with
duplicate,self‐monitoringVTLservernodesandredundant,primaryandstandby
pathsbetweenbackupapplicationsandVTLdata.
■Encryptionandsecuredatadestruction
Toensurethatthedatathatyouexporttophysicaltapeisconfidentialandsecure,
VTLoffersaSecureTapeOptionthatusestheAdvancedEncryptionStandard
(AES)algorithmpublishedbytheNationalInstituteofStandardsandTechnology,
anagencyoftheU.S.government.

Features
96267 • G Chapter 1 Introduction: VTL appliances and enterprise data-protection 3
TheShredfeatureinsuresmilitarystandard,securedatadestructionby
overwritingvirtualtapewithrandombitpatterns.Datadestructionjobsare
queuedsothattheshredprocessdoesnothaveanexcessiveimpactupon
performance.
■Datacompression
SunVTLPlus2.0supportsbothsoftware‐basedandhardware‐baseddata
compression.
Bothdata‐compressiontechnologiesoffersimilarfunctionality.Botharebasedon
theLZOalgorithm.Whennecessary,eithercanincreasetheamountofdatathat
willfitonavirtualtapeofagivencapacity.Compressionratioscanapproach2:1
fordatasetsmadeupofhighlycompressiblefiletypes,suchasplaintextand
uncompressedbitmappedimages(incompressiblefiletypes,suchasZIParchives,
GIFimages,andJPGimagesreducetheattainablecompressionproportionately).
However,theoptionalVTLPlus2.0compressionhardwareofferssignificantly
higherthroughputperformancecomparedwiththesoftware‐onlyapproach.
SpecializedASICs(application‐specificintegratedcircuits)ontheoptional
compressioncardsperformthecalculationsthatsoftware‐onlysolutionsmust
performonthesystemCPU.
■SupportforSunStorageTekACSLSandLibraryStationlibrary‐management
software
ACSLSandLibraryStationsupportmakesahighdegreeofintegrationpossible
betweenVTLsolutionsandcomplexenterprisestorageenvironmentsthatinclude
largelibrarieswithmultiplepartitionsandmixedopensystemsandmainframe
systems.SunVTLvirtuallibrariescancacheorcopytapevolumestostorage
poolsonshared,ACSLS‐managedlibraries.Alternatively,ACSLScanbe
configuredtomanagevirtuallibraries.
■Emailnotifications
TheVTLemailalertsfeaturemonitorsanextensiblesetofpre‐definedcritical
systemfunctionsandautomaticallynotifiesalocalsystemadministratorbyemail.
YoucanextendormodifytheCallHomemonitoringscriptstocustomize
monitoringforyourneeds.
■X‐raydiagnostics
TheX‐rayfeaturecombinessnapshotsofthecurrentstateoftheappliance,its
configuration,anditsenvironmentwithsystemeventlogsandsavestheresultin
astandard,tape‐archive(tar)format.
KeyVTLfeaturesarediscussedinmoredetaillaterinthischapter.

Advantages of VTL tape virtualization
4VTL User Guide • May 2008 G • 96267
AdvantagesofVTLtapevirtualization
AddingSunStorageTekVirtualTapeLibraryappliancestoanexistingtape‐based
backuparchitecturecanthusrealizethefollowingadvantages:
■“Shorterruntimesandreduceddependencyonbackupwindows”onpage 4
■“Shorterruntimesfornon‐sequentialbackupjobs”onpage 5
■“Improvedreliability”onpage 5
■“Betterutilizationoftapesubsystems”onpage 5
■“Larger,moreflexiblelibraries”onpage 6
■“CompatibilitywithACSLSmanagementsoftware”onpage 6
■“Truetapevirtualizationwithdynamicallyallocateddiskspace”onpage 7.
Shorterruntimesandreduceddependencyon
backupwindows
VTLappliancescanhandleanarrowbackupwindowbyusingnumbersofvirtual
drivesoperatinginparallel,somethingthatwouldbehighlyimpracticalwith
physicaltapedrives.Inthisway,thecritical,firstcopyoftheprimarydataisreliably
transferredtodisk‐basedvirtualtapeinminimumtime.Thereafter,vaulting
softwareand/orVTLtape‐cachingfeaturescancopythebackupfromvirtualto
physicalmediausingasmaller,moreeconomicalnumberofphysicaldrives.Seethe
figurebelow:
Multiple virtual drives speed backup during the critical backup window
virtual
tape
drives
virtual library physical library
primary storage
physical
tape
drives
Back up to multiple virtual tape
drives during the critical
backup window
At other times, copy virtual tapes to
physical media using one or two
dedicated tape drives
backup
window

Advantages of VTL tape virtualization
96267 • G Chapter 1 Introduction: VTL appliances and enterprise data-protection 5
Shorterruntimesfornon‐sequentialbackupjobs
Disk‐basedVTLsystemsreduceruntimewhenstorageoperationsarepoorly
matchedtotheoperationalcharacteristicsoftapebackupsystems.Properly
configured,streamingtapebackupsachievetransferratesthatareashighasor
higherthanthoseattainablebydisktechnology.Butmanycommonjobs—suchas
incrementalsandfullbackupsofworkstations—producesemi‐randomI/O.Non‐
sequentialI/Okeepstapedrivesbusymounting,unmounting,andpositioning
media,greatlyreducingthroughput.Disk‐basedsecondarystorageismuchbetter
suitedtothesesemi‐randombackupjobs.
Improvedreliability
Disk‐basedVTLsystemscansignificantlyincreasethereliabilityofthebackup
process.Backupjobsaremorelikelytosucceedthefirsttime,becausethecritical
step—thecreationofacopyofthedata—isasimple,fastwritetoaRAIDsubsystem.
Jammedtapes,lackofreadymedia,andoff‐linedrivesnolongerruinjobs.Seethe
figurebelow:
Backup is more reliable with virtual tape libraries
Betterutilizationoftapesubsystems
Disk‐basedVTLsystemscanimproveutilization,performance,andreliabilityof
tape‐storagesubsystems.Whennon‐sequentialI/Oisbackeduptodisk,tapecanbe
reservedforsequentialjobsthatcanstreamaphysicaltapedrive.Large‐scalefull
backupscan,forinstance,godirectlytotape,insuringmaximumperformance.Jobs
virtual
library
physical
library
primary storage A backup to physical tape can fail when a tape
drive jams or media breaks, because a retry may
not be possible before the backup window closes.
physical
library
backupwindow
FAILURE!
SUCCESS!
A backup to disk-based virtual media always
succeeds, so all data is copied to secondary
media before the backup window closes.
Virtual volumes are
subsequently copied to
physical media outside
the backup window. If
problemsarise,copyjobs
can be retried later.

Advantages of VTL tape virtualization
6VTL User Guide • May 2008 G • 96267
thatproduceintermittentornon‐sequentialI/O,suchasincrementalsandbackupsof
workstations,arecopiedtotapeonlyaftertheyhavebeenbackeduptodiskand
incorporatedintolarge,sequentialbackupsets.Thisapproachusestapedrives
continuously,atclosetotheirmaximumthroughput.Thedrivesspendlesstimeidle,
sincetheymountandrepositionlessoften.Fewerdrivesandtapesareneededfora
givenworkload.Devicesandmediasufferlesswearandtear.
Improvedutilizationofbackupmedia
Tapevirtualizationletsyoucreateemulatedtapevolumesthataremorecloselysized
totheaveragesizeofyourbackupmedia.Ifyoudonotdecidetousetapecaching
(see“A u t o m a t e d TapeCaching”onpage 12),yousetthemaximumcapacityofyour
virtualtapesto50‐60GBortotheaveragesizeofyourbackupjobs(whicheveris
larger).Thisapproachminimizeswastedspaceinthecriticaldiskcache,wherethe
firstcopyofeachbackupjobisstored,andmakesamaximumnumberofcartridges
availableforbackupjobsatanygiventime.Yourcopy/vaultsoftwarecanthen
consolidatethesesmallervolumesontofull‐sizedphysicaltapecartridgesoutside
thebackupwindow.Ifyoualsoenlargethesizeofthelibrary,asdescribedbelow,
youcanaccomodatealargertotalnumberofthesesmallervirtualtapes.
Ifyouadopttapecaching,youcannotsizevirtualtapesthisway,since,asweshall
see,thediskandphysical‐tapeimagesofthevirtualtapemustbelogicallyidentical.
Larger,moreflexiblelibraries
TheSun VTL virtuallibraryfaithfullyemulatesaSunL700physicaltapelibrary.
But,whiletheL700has678slots,theSun VTLcanhaveupto64000inanon‐tape
cachingsolution,dependingonthebackupapplication(see“A u t o m a t e d Tape
Caching”onpage 12).Thisisaparticularlyimportantconsiderationifyouimprove
mediautilizationbyreducingthesizeofyourvirtualtapevolumes,asdescribed
above.Onelargevirtuallibrarycan,onitsown,servealltheneedsofabackup
applicationmasterserver.
CompatibilitywithACSLSmanagementsoftware
Tapevirtualizationletsyoucontroldisk‐basedvirtuallibrarieswiththesame
industry‐standard,SunACSLSsoftwarethatcontrolsphysicaltapelibraries.ACSLS
addsanadditionalvirtualizationlayertoyourbackupenvironment,further
reducingdisruptionstoestablishedinfrastructureandpolicieswhile,atthesame
time,bringingnewcapabilities.