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Note: Thisfeatureisuseful when,forexample,anUPDATEstatementhasbrokenadatabasebutyou did notnotice
thedamageforseveralhours.Usethisfeatureto roll backto thelastsnapshottakenbeforeanincidentoccurred.The
snapshotisoneofseveralvolumesintheSAN,eachrepresentingasnapshotofthemainvolumeforthatserverona
differentdate,atadifferenttime.
portabledocumentformat(PDF). Astandardspecified byAdobeSystemsIncorporatedfortheelectronic
distributionofdocuments.PDFfiles arecompact;canbedistributedgloballybye-mail,theweb,intranets,or
CD-ROM;and canbeviewedwiththeAcrobatReader.
portal. Awebportalorself-serviceportalisawebsitethatfunctions asapointofaccesstoinformationonthe
Internet.Aportal presentsinformationfromdiversesourcesinaunified way.
R
RecoveryHost. Ahostcomputerthatdrivestherecoveryandrestorationofproductiondataafterafailure.
Recoverypointobjective(RPO). Theacceptableamountofdatalossmeasured intime.Therecoverypointobjective
isthepointintimeto whichyou mustrecoverdataasdefinedbyyourorganization.
Recoverytimeobjective(RTO). Recoverytimeobjective(RTO).Themaximumtolerablelengthoftimethata
computer,system,network,orapplicationcantypicallybedown(until systembootstart)afterafailureordisaster
occurs.TheRTOisafunctionoftheextentto whichtheinterruptiondisruptsnormaloperationsandtheamountof
revenuelostbyunitoftimeasaresultofthedisaster.
Red HatEnterpriseLinux(RHEL). ALinux-based operatingsystemproducedbyRedHatandtargetedtowardthe
commercialmarket,includingmainframes.
replicationagent. Replicationagentscarryoutmanyofthetasksassociated withreplication,includingcreating
copiesofschemaand data,detectingupdatesatthePublisherorSubscriber,and propagatingchangesbetween
servers.Bydefault,replicationagentsrununderMicrosoftSQLServerAgentjobsteps.
replicationclient. ThissoftwarepackageinstallsoneverysourceserverthattheuserwishestoincludeinaVSR
solution.Itactsasthemainpointofcommunicationbetweenthecustomer'sserverandtheVSRManagementServer.
replicationensemble. TheVSRcomponentthatholdsalloftheserversusedinaVSRCinstallationto replicate
customerproductiondata.YoucanhavemultipleReplicationEnsembleswithinaVSRPOD.
replicationserver. TheserverbeingreplicatedbytheIBMSmartCloudVSRservice.
RHEL. SeeRed HatEnterpriseLinux (RHEL).
role. Aserverroleisasetofsoftwareprogramsthat,whentheyareinstalled andproperlyconfigured,letsa
computerperformaspecificfunctionformultipleusersorothercomputerswithinanetwork.Generally,rolesshare
thefollowingcharacteristics:
v Theydescribetheprimaryfunction,purpose,oruseofacomputer.Aspecificcomputercanbededicatedto
performasinglerolethatisheavilyused intheenterprise,ormayperformmultiplerolesifeachroleisonly
lightlyused intheenterprise.
v Theyprovideusersthroughoutanorganizationaccesstoresourcesmanagedbyothercomputers,suchasWeb
sites,printers,orfilesthatarestoredondifferentcomputers.
v Theytypicallyincludetheirowndatabasesthatcanqueueuserorcomputerrequests,orrecordinformationabout
networkusersandcomputersthatrelatestotherole.Forexample,ActiveDirectoryDomainServicesincludesa
databaseforstoringthenamesandhierarchicalrelationshipsofall computersinanetwork.
v Assoonastheyareproperlyinstalledandconfigured,rolesfunctionautomatically.Thisallowsthecomputerson
whichtheyareinstalledto performprescribedtaskswithlimitedusercommandsorsupervision.
Seealso:
v User
v CustomerVSRAdministrator
v IBMVSRAdministrator
roleservices. Softwareprogramsthatprovidethefunctionalityofarole.Whenyouinstallarole,youcanchoose
whichroleservicestheroleprovidesforotherusersandcomputers inyourenterprise.Someroles,suchasDNS
R
Glossary
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