Checkmssql2005

mssql2005  时间:2021-05-05  阅读:()
DELLPOWERSOLUTIONSReprintedfromDellPowerSolutions,February2006.
Copyright2006DellInc.
Allrightsreserved.
February200626DATABASES:SQLSERVER2005Enterprisedatacentersthathostbusiness-criticalappli-cationsanddatabasescanbeatriskfromfailuresanddisasters.
Availabilityandrecoverabilitybecomecrucialforbusinessoperations.
Currentdatabaseavailabilitytechnolo-giesvaryintheircomplexity,cost,levelofautomation,incurreddowntime,andsupporteddistance.
Amajorchal-lengeforanenterpriseisdeterminingthemostcost-effectiveandleastcomplexsolutiontohelpensuredatabaseavail-abilityandmeetbusinessneeds.
MicrosoftSQLServer2005introducesseveralhigh-availabilityfeaturesandfeatureenhancementsfortheSQLServerdatabaseplatform.
FailoverclusteringFailoverclusteringwithMicrosoftClusterService(MSCS)isapopularwaytoachievehighavailabilityforSQLServer.
WithMSCS,multipleserversornodesarelinkedtofunctionasasinglesystemandprovideanautomaticfailoversolution.
Enterprisesareconnectedtovirtualserv-ersandnotphysicalservers;eachactivephysicalservermayhostoneormorevirtualservers.
Ifoneofthephysicalserversfailsbecauseofeitherahardwareorsoftwareproblem,MSCSdetectsthefailureandmovesresourcesthatresideonthefailingserver—includingthevirtualserver(s)—tooneormoreremainingphysicalservers.
EndusersconnectedtothefailedserverobserveonlyamomentarydelayinaccessingitsresourceswhileMSCSrestartsSQLServerservicesontheremainingserver(s)andremapsthevirtualserverconnections.
Installingafailoverclusterrequiresthefollowing:MicrosoftWindows2000Server(AdvancedServerorDatacenterServer)orMicrosoftWindowsServer2003(EnterpriseEdition,DatacenterEdition,Enterprisex64Edition,orDatacenterx64Edition)MicrosoftSQLServer2005(StandardEditionorEnterpriseEdition)SharedstoragebasedonSCSI,FibreChannel,orSerialAttachedSCSIAllcomponents(server,hostbusadapter,andstor-agesystem)andtheclustersolutionlistedintheMicrosoftWindowsServerCatalogFigure1showstwotypicaltwo-nodefailoverclusterconfigurationsforSQLServer2005,oneinactive/passiveBYANANDASANKARAN,DATNGUYEN,ANDNAMNGUYENExploringHigh-AvailabilityFeaturesinMicrosoftSQLServer2005sMicrosoftSQLServer2005offersfailoverclustering,databasemirroring,logshipping,replication,anddatabasesnapshotfeaturesthatcanhelpsafeguardanenterprise'scriticaldataandoperations.
Thisarticlediscussesthesefeaturesandtheirassociatedtrade-offs.
RelatedCategories:ClusteringDatabaseHighavailability(HA)MicrosoftSQLServer2005Visitwww.
dell.
com/powersolutionsforthecompletecategoryindex.
DATABASES:SQLSERVER2005www.
dell.
com/powersolutionsReprintedfromDellPowerSolutions,February2006.
Copyright2006DellInc.
Allrightsreserved.
DELLPOWERSOLUTIONS27modeandoneinactive/activemode.
Inafailoverclusterenvi-ronment,SQLServer2005offersseveraladditionalfeaturesandimprovementscomparedtoSQLServer2000:Supportformultinodeclustering:StandardEditionallowsuptotwo-nodeclusteringandEnterpriseEditionuptoeight-nodeclustering.
SupportforSQLservices:AnalysisServicesfeatureoffersmulti-instancesupportandfull-textindexing.
Easierinstallation:SystemConfigurationCheckautomati-callydetectsandinstallsSQLServerasvirtualserversacrossthenodesinthecluster.
DatabasemirroringDatabasemirroringisdesignedtoaugmenttheavailabilityofSQLServer2005.
Withthisfeature,transactionstoadatabasehostedonaSQLServerinstance,referredtoastheprincipal,canbecon-tinuouslyduplicatedinrealtimeontoacopyhostedonanotherinstance,referredtoasthemirror.
Theprincipalandmirrorserversareconsideredpartnersinadatabasemirroringsession.
Transac-tions(suchasinsertions,updates,anddeletions)ontheprincipaldatabaseareduplicatedbycontinuouslysendingtransactionlogrecordstothemirroroverthenetwork(seeFigure2).
Themirrorreceivesthelogrecordscontinuouslyandrestoresthem.
Iftheprincipalormirrorserverincursafailure,themirror-ingsessionisdisconnected.
Beforestartingthemirroringsession,administratorsmustinitializethemirrordatabasefromaprincipaldatabasefull-restorewiththeNORECOVERYoption.
Besidestheprimaryandmirror,amirroringsessionmayincludeanoptionalthirdserver,referredtoasthewitness.
Thewitnessserverenablesautomaticfailoverafteraprincipalserverfailurebypromotingthemirrortofunctionastheprincipal.
Usingawitnessserverhelpsachieveaquorumandpreventsaccidentalpromotionofthemirrordatabasethatresultsfromcommunicationfailuresbetweentheprincipalandmirror.
Databasemirroringrequiresthefollowingconfiguration:Theprimaryandmirrordatabasesmustbehostedonsepa-rateSQLServer2005instances.
TheprincipaldatabasemustbesettotheFullRecoverymodel,nottheBulk-LoggedRecoveryorSimpleRecoverymodel.
Databasemirroringcanbeconfiguredinanyofthefollowingthreeoperatingmodesbasedontransactionsafetylevelandthepresenceofawitnessserver:High-availabilitymode:Inthismode,logrecordsaretrans-ferredsynchronouslyfromtheprincipaldatabasetothemirror.
Theprincipalwaitsforanacknowledgmentfromthemirrorbefore"hardening"logrecordstoitsdisk.
Inadditiontoprovidingsynchronoustransfer,thismodeusesawitnessservertoenableautomaticfailover.
High-protectionmode:Thismodeissimilartothehigh-availabilitymodeexceptthatitdoesnotsupportawitnessserver,andthusautomaticfailoverisnotpossible.
However,failovercanbeperformedmanuallytopromotethemirrordatabase.
Becausethelogrecordsaretransferredsynchro-nouslyinthismode,themirrordatabaseissynchronousandconsistentwiththeprincipal.
High-performancemode:Inthismode,logrecordsaretransferredasynchronouslyfromtheprincipaltothemirrordatabase.
Theprincipaldoesnotwaitforanacknowledg-mentfromthemirrorbefore"hardening"itslogstothedisk,Figure1.
FailoverclusterconfigurationsforSQLServer2005SQLServer2005db1db2SQLServer2005HeartbeatLANActivePassiveSQLServer2005db1SQLServer2005HeartbeatLANActiveActivedb2Figure2.
Databasemirroringfordatabasedb1inhigh-availabilitymodeLANPrincipalMirrordb1db2db3SQLServer2005db5db6SQLServer2005SQLServer2005db1TransactionlogrecordsLogrecoveryWitnessDATABASES:SQLSERVER2005DELLPOWERSOLUTIONSReprintedfromDellPowerSolutions,February2006.
Copyright2006DellInc.
Allrightsreserved.
February200628andthemirrorisnotguaranteedtobesynchronouswiththeprincipalatanypoint.
Thismodedoesnotsupportawit-nessserver,andthusneitherautomaticnormanualfailoverispossible.
However,aforcedfailovercanbeperformedtorecoverthemirror,withsomedatalossoccurringbecausemirroringisasynchronous.
Akeyadvantageofdatabasemirroringisthatitprovidesquickfailoverandhighavailabilitywithminimalhardwarecostandcomplexity.
Formerly,suchSQLServermirroringsolutionswereoftenfeasibleonlywithexpensive,proprietaryhardware-basedmechanisms.
Withacceptablelatenciesandbandwidth,mirroringcanbedeployedoveralong-distancewideareanetwork(WAN)aspartofadisasterrecoverysolution.
Duringthemirroringsession,themirrordata-baseisnotavailableforclientaccessbecauseitisinarecoverystate,butadatabasesnapshotcanbecreatedonthemirrorforlimitedreporting.
Onlyonemirrordatabasecanbeestablishedforaprinci-paldatabase.
However,theparticipatingSQLServerinstancescanassumediffer-entrolesfordifferentmirror-ingsessions.
Forexample,aSQLServerinstancecanserveasaprincipalforonedatabase,asamirrorforanotherdatabase,andasawitnessforyetanothermirroringsession.
Thenotionofavirtualserver,asisusedinfailoverclustering,doesnotexist.
However,MicrosoftADO.
NETprovidesanapplicationprogramminginterface(API)forclientstoautomaticallyreconnecttothemirrorserverduringfailures.
LogshippingLogshippingissimilartodatabasemirroring.
Itallowsadatabasehostedonaprimaryservertoautomaticallysendtransactionlogstoasecondarydatabaseforduplication.
Thelogrecordsarenottransferredcontinuouslyasindatabasemirroring,butratherinintervals.
Logshippingcomprisesbackingupthetransactionlogsontheprimaryserverinstance,copyingthebacked-uplogstothesecondaryserverinstance,andrestoringthecopiedlogsonthesecondaryserverinstanceperiodically.
TheprimarydatabaseshouldbeconfiguredfortheFullRecoveryorBulk-LoggedRecoverymodel.
ThesecondarydatabaseshouldbeinitializedbyafullrecoveryoftheprimarydatabasewiththeNORECOVERYorSTANDBYoption.
Logshippingcanoptionallyincludeathirdservernamed"mon-itor"torecordthehistoryoflog-shippingoperationsandtoraisealertsduringfailures.
Log-shippingoperationsarecarriedoutbyfourMicrosoftSQLServeragentjobs:backupjob,copyjob,restorejob,andalertjob.
Duringlogshipping,thesecondarydatabaseisnotcompletelysynchronizedwiththeprimarydatabase.
Also,logshippingdoesnotprovideautomaticfailovertothesecondaryserverduringafailure.
Logshippingsupportsmultiplesecondaryserversforaprimaryserver.
Inaddition,aSQLServerinstancecanfunctionasasecondaryormonitorserverformultipleprimaryservers.
Thesecondaryservercanbeuseddirectlyforlimitedqueryprocessing.
Logshippingcanbeusedinscenarioswheremultipledestina-tionserversareneededandwheredelaysinrestoringlogsontheduplicateareacceptable.
ReplicationReplicationisasetoftechnologiesfordistributingdataanddata-baseobjectsacrossMicrosoftSQLServerdatabasesoveranet-work.
Replicationinvolvesapublisherdatabaseinstancethatmakesdataavailableforcopying,adistributorinstanceforcopyingdataandmaintainingmetadata,andsubscriberinstancesthatcanreceivereplicateddata.
SQLServer2005providesthreetypesofreplicationtech-nologiessuitablefordifferentneeds:transactional,merge,andsnapshot.
SQLServer2005addsenhancementstotheserepli-cationmethodstohelpimprovescalability,performance,andmonitoringcapabilities.
Someoftheimprovementsincludeadditionalreplicationdatatypes,supportforpartitionedtablesandfull-textindex,directDataDefinitionLanguage(DDL)replicationforschemachanges,andreplicationfromOracledatabases.
Intransactionalreplication,SQLServer2005addsanimpor-tantfeaturecalledpeer-to-peerreplication,whichenhancestheexistingbidirectionalreplicationoption.
Advantagesofreplicateddatabasesincludedataloadbalancinganddisasterrecovery.
Withthepeer-to-peerreplicationfeature,administratorscansetupmultiplepeer-to-peertransactionalreplicationpairsamongdifferentdatacenters.
Thatway,ifonedatacenterisdown,itcanbefailedovertoitspeercenter(s).
Althoughthereisnolimittothenumberofnodesinapeer-to-peertopology,man-ageabilityofthepeer-to-peerrelationshipsbetweennodescanbecomeaconstraint.
SQLServer2005providesthreetypesofreplicationtechnologiessuitablefordifferentneeds:transactional,merge,andsnapshot.
SQLServer2005addsenhancementstothesereplicationmethodstohelpimprovescalability,performance,andmonitoringcapabilities.
DATABASES:SQLSERVER2005www.
dell.
com/powersolutionsReprintedfromDellPowerSolutions,February2006.
Copyright2006DellInc.
Allrightsreserved.
DELLPOWERSOLUTIONS29DatabasesnapshotsAdministrativeandapplicationerrorscanbeamajorcauseofdatabasedowntime.
SQLServer2005introducesafeaturecalledData-baseSnapshotstohelpprotectadatabasefromerroneoususeroperationsandtoaugmentdatabasebackupandrestoreoperations.
TheDatabaseSnapshotsfeatureallowsrecoveryfromusererrorsbyallowingthedatabasestatetoreverttoapointintimebeforetheerror(s)occurred.
Itworksinstand-alone,failoverclus-tering,anddatabasemirroringenvironments.
However,itdoesnotworkwithalog-shippingsecondarydatabase.
Adatabasesnapshotisasnapshotofanentiredatabaseatagiventime.
Thesnapshotiscreatedinstantlyandcanbeusedforread-onlytaskssuchasreporting.
Asnapshotmusthavebeencre-atedbeforetheerroroccurredforanadministratortorestorethedatabasetoaconsistentstate.
Snapshotcreationdoesnotimposerestrictionsonthebasedatabaseoperations.
Administratorscancreatemultiplesnapshotsfromadatabaseaswell.
TheSQLServer2005DatabaseSnapshotfeatureemploysacopy-on-writemechanism.
Onlychangestothebasedatabase—nottheentirebasedatabase—arerecordedafterthesnapshothasbeentaken.
Thesnapshotisapointerimagetothebasedatabase.
Itsharestheunchangedpagesofthebasedatabaseandrequiresonlyextrastorageforchangedpages.
TheDatabaseSnapshotmechanismisillustratedinFigure3.
TheDatabaseSnapshotfeatureisdesignedtobeextremelyspace-efficient.
Anymodificationsuchasawrite(step1inFigure3)tothebasedatabaseafterasnapshotistakenwillberecorded(step2inFigure3)aspartofthetargetsnapshot.
IfI/Oreadrequests(step3inFigure3)aretoblocksthathavenotchangedsincethesnapshotwascreated,thentherequestwillreadfromthebasedatabase.
IfI/Orequestsaretoblocksthathavechangedsincesnapshotcreation,thentherequestwillbereadfromthesnapshot.
Figure4summarizesthehigh-availabilityfeaturesandoptionsavailableinMicrosoftSQLServer2005.
Ahigh-availabilitydatabaseplatformMicrosoftSQLServer2005offersseveralfeaturesthataredesignedtohelpaugmentavailabilityofdata.
DellPowerEdgeservers,DellPowerVaultstorage,andDell/EMCstoragearealsodesignedwithabroadarrayofredundanthardwareandsoftwarefeaturestomaximizehardwareavailability.
ThefeaturesinDellhardwareandSQLServer2005provideanintegrated,industry-standardapproachtohighdatabaseavailability.
Acombinationofthesecomponentscangreatlybenefitenterpriseswithhigh-availabilitydatabaserequirements.
AnandaSankaranisasystemsengineerintheHigh-AvailabilityClusterDevelopmentGroupatDell.
Hiscurrentinterestsrelatedtohigh-availabilityclusteringincludestoragesystems,applicationperformance,businessconti-nuity,andclustermanagement.
Anandahasamaster'sdegreeinComputerSciencefromTexasA&MUniversity.
DatNguyenisasystemsengineerintheHigh-AvailabilityClusterDevelop-mentGroupatDell.
Hisresponsibilitiesincludedevelopingstorageareanetwork(SAN)–basedhigh-availabilityclusteringproducts.
Hiscurrentinterestsareinenterprisestorageproductsandtechnologies.
DathasaB.
S.
inElectricalEngineeringfromtheUniversityofHouston.
NamNguyenisaseniorconsultantintheHigh-AvailabilityClusterDevelop-mentGroupatDell,andtheleadengineerforDellFibreChannelPowerEdgeClusterproducts.
Hiscurrentinterestsincludebusinesscontinuity,cluster-ing,andstoragetechnologies.
HehasaB.
S.
andanM.
S.
inElectricalEngineeringfromTheUniversityofTexasatAustin.
FORMOREINFORMATIONMicrosoftSQLServer2005:www.
dell.
com/sqlwww.
microsoft.
com/sqlFigure3.
DatabaseSnapshotmechanisminSQLServer2005123456789101112123456789101112123SnapshotsPageBasedatabaseFigure4.
High-availabilityoptionsandfeaturesinSQLServer2005Solution-specicAutomaticcerticationGranularityDatalossfailoverDowntimerequirementsFailoverclusteringSystemandNoYesApproximatelyClustersolutionlisteddatabase20secondsplusinMicrosoftWindowsdatabaserecoverytimeServerCatalogDatabasemirroringDatabaseDependsonYesLessthan3secondsNooperatingmodePeer-to-peerreplicationTableorviewSomeOptionalVariable(littletonone)NoLogshippingDatabaseSomeNoVariableNoDatabasesnapshotsTableorviewSomeNoVariableNo

ZJI-全场八折优惠,香港服务器 600元起,还有日本/美国/韩国服务器

月付/年付优惠码:zji  下物理服务器/VDS/虚拟主机空间订单八折终身优惠(长期有效)一、ZJI官网点击直达ZJI官方网站二、特惠香港日本服务器香港大埔:http://hkdb.speedtest.zji.net/香港葵湾:http://hkkw.speedtest.zji.net/日本大阪:http://jpsk.speedtest.zji.net/日本大阪一型 ...

HostWebis:美国/法国便宜服务器,100Mbps不限流量,高配置大硬盘,$44/月起

hostwebis怎么样?hostwebis昨天在webhosting发布了几款美国高配置大硬盘机器,但报价需要联系客服。看了下该商家的其它产品,发现几款美国服务器、法国服务器还比较实惠,100Mbps不限流量,高配置大硬盘,$44/月起,有兴趣的可以关注一下。HostWebis是一家国外主机品牌,官网宣称1998年就成立了,根据目标市场的不同,以不同品牌名称提供网络托管服务。2003年,通过与W...

腾讯云轻量服务器两款低价年付套餐 2核4GB内存8M带宽 年74元

昨天,有在"阿里云秋季促销活动 轻量云服务器2G5M配置新购年60元"文章中记录到阿里云轻量服务器2GB内存、5M带宽一年60元的活动,当然这个也是国内机房的。我们很多人都清楚备案是需要接入的,如果我们在其他服务商的域名备案的,那是不能解析的。除非我们不是用来建站,而是用来云端的,是可以用的。这不看到其对手腾讯云也有推出两款轻量服务器活动。其中一款是4GB内存、8M带宽,这个比阿里云还要狠。这个真...

mssql2005为你推荐
支持ipad搜狗360因为我做百度,搜狗,360,神马竞价推广已经有一年多了,所以请问下,网上有哪些平台可以接竞价的单呢?中国企业在线中金在线和中金公司有关系吗全国企业信息查询网上如何怎么查询全国企业信用信息公示系统查询美要求解锁iPhone美版解锁的iphone在大陆怎么用支付宝注册网站支付宝申请流程是怎么样的??360防火墙在哪里360防火墙Aliasedinternal免费代理加盟怎样免费加盟代理淘宝社区动力你为什么想当一名社区工作者
虚拟主机排名 国内vps 欧洲免费vps 阿里云邮箱登陆首页 a2hosting jsp主机 php主机 光棍节日志 realvnc 创梦 双线主机 国外ip加速器 工信部网站备案查询 谷歌台湾 开心online reboot asp.net虚拟主机 美国vpn服务器 pptpvpn 赵荣博客 更多