11 在设计Exchange Server 部署方案前的注意事项.docx

11 在设计Exchange Server 部署方案前的注意事项.docx

《11 在设计Exchange Server 部署方案前的注意事项.docx》由会员分享，可在线阅读，更多相关《11 在设计Exchange Server 部署方案前的注意事项.docx（29页珍藏版）》请在冰豆网上搜索。

11在设计ExchangeServer部署方案前的注意事项

Exchange2003DesignConsiderations

BeforeyoubeginplanningaMicrosoft® ExchangeServer 2003messagingsystem,youneedtogatheralargeamountofbusinessandtechnicalinformation.Manycompanieshavetheirownsystemdevelopmentmethodologiestoguidethemthroughtheprocessofdesigningorupgradingsystems.Suchmethodologiesgenerallybeginwithgatheringrequirementsandassessingthecurrentenvironment.Evenifyourcompanydoesnotfollowaformalmethodology,theproperapproachtotheplanningphasebeginswiththesefirststeps.

PlanningyourExchangeServer 2003messagingsystemtypicallyprogressesasfollows:

•

AssessingYourExchangeServer2003DesignRequirements   First,evaluateyourbusiness,administrative,user,andsecurityrequirements,andconductatechnicalassessmentoftheenvironmentinwhichyouplantodeploythemessagingsystem.

•

UnderstandingYourCurrentNetworkEnvironment   Next,assessyourtechnicalsolutions,anddeterminethetargetExchangemessagingsystemdesign.

•

PlanningActiveDirectorywithExchangeServerinMind    Alongwithassessingyourcurrentenvironmentfromaphysicalstandpoint,youshouldunderstandhowWindowsServerandActiveDirectoryaredeployedinyourorganization.

•

UnderstandingVersionsofExchange,Windows,andOutlook   Finally,performagapanalysistodeterminewhatyouneedtoaccomplishtomovefromyourexistingenvironmenttoyourtargetdesign.

PuttingItAllTogether

WhenplanningtheplacementofExchangeserversandtheadministrationofdirectoriesandservers,itisusuallyrecommendedthatyoustartwithacentralizedmodelandaddservers,routinggroups,andadministrativegroupsonlywhennecessary.WiththefeaturesavailableinExchange 2003,WindowsServer 2003,andOutlook 2003,businessesmaybeencouragedtoadoptmorecentralizedmessagingsystemsthanhavebeenpossibleinthepast.Inaddition,withtheproliferationofhigherspeedandhigherbandwidthconnections,companiesmadeupofgeographicallydispersedofficescanconsidercentralizingtheirhardwareandadministrationsothattheycanreducethenumberofserversrequiredinremotelocations.Thefactorsthatdrivecentralizationbreakdownintothreemaincategories:

•

Centralizingthehardwarethatservesremoteoffices   Communicationbetweentheclientcomputerandserveriscompressed,andtrafficissignificantlyreducedduetoimprovementsinOutlookRPCcommunicationandOutlookWebAccess 2003compression.Exchange 2003hasanumberoffeaturesthathelpyouconsolidateyoursitesandadministrativegroups.Inaddition,CachedExchangeModeinOutlook 2003helpsyoureducethenumberofserverslocatedinremotelocationsthatareconnectedwithhighlatency.

•

Reducingthenumberofservers   Toreducetotalcostofownership,itiscommonforcompaniestotrytoreducethenumberofserversneededtosustainthemessagingneedsoftheirusers.Yourcompanymaydecidetoreducethenumberofserversneededbyinvestinginhigh-endservers,includinghighperformanceprocessorsandserverswithmultipleprocessors.WindowsServer 2003andExchange 2003alsosupporthyperthreadingtechnology,inwhichasingleprocessorisabletorunmultiplethreads（andappearsastwoprocessorsinsteadofone）.Theprocessormustbehyperthreading-enabledandyoumustuseWindowsServer 2003andExchange 2003.

•

Centralizingserveranddirectoryadministration   Companiesmaywanttocombineandcentralizetheiradministrativeworkforcetoreduceadministrativecosts.OnefeaturethatsimplifiesadministrationistheimprovedmethodformovingmailboxesinExchangeSystemManager.Administratorscanmovemailboxesmoreefficientlyandcanrecoverfromfailuresmoreeasilywhencorruptitemsareencountered.Inaddition,administratorscanschedulemailboxmovestobeginandendatacertaintime.

AssessingYourExchangeServer2003DesignRequirements

Business,administrative,user,andsecurityrequirementsdirectlyaffectthedesignofyourExchangeServer2003messagingsystem.Becausecompaniesusevariousmethodologiestogatheranddocumentrequirementsuniquetotheirsituations,thissectiondoesnotprovideanexhaustivelistofallpossiblerequirements.Instead,itfocusesonsomegeneraltypesofrequirementsandtheissuesassociatedwitheachthatcaninfluenceyourplanning.

BusinessRequirements

SomeofthebusinessrequirementsthatyouneedtoidentifybeforeyoubeginplanninganExchangemessagingsystemincludethefollowing:

•

ServiceLevelAgreements（SLAs）

•

Networkandhardwarecostconstraints

•

Softwarecostconstraints

Businessrequirements,particularlycostconstraints,determinetheextenttowhichyoumustworkwithintheexistinginfrastructureorwhetheritisfeasibletoupgradethenetworkinfrastructure,hardware,andsoftware.

ServiceLevelAgreements

ServiceLevelAgreement（SLA）requirementsdeterminehowthingssuchasstorage,clustering,andbackupandrecoveryfactorintoyoursystem.WhenassessingSLAs,besuretodetermineyourcompany'sexpectationsregardingavailabilityandrecoverability,includingmessagedeliverytime,percentageofserveruptime,amountofstorageperuser,andamountoftimetorecoveranExchangedatabase.Identifythehoursofregularoperationandtheexpectationsaroundplanneddowntime.Inaddition,identifythecompany'sestimatedcostofunplanneddowntimesothatyoucandesigntheproperamountoffaulttoleranceintoyourmessagingsystem.

NewfeaturesinExchange Server2003andWindowsServer 2003mayaffectthewayyoudesignyoursystemtomeetSLAs.Inparticular,thenewVolumeShadowCopyservicemaychallengethelimitsthatyourSLAspreviouslyimposed.Becausebackupscantakealongtimetocomplete,youpreviouslymayhavehadtolimitthenumberofusersyouhostedoneachmailboxstoretomeetSLAlimitationsforuptime.WithVolumeShadowCopyservice,however,thebackupisperformedfromtheshadowcopy,sothereisnoaffectonthedatabasethattheapplicationsareusing.VolumeShadowCopyserviceallowsyoutobackupExchangedata（oranyapplicationdata）quicklyandwithminimalimpacttoyoure-mailclients.Thishelpsyousupportlargerdatabasesandmoreusersperserver.WhenusedinconjunctionwithsoftwareandhardwarethatsupportsWindowsServer 2003VolumeShadowCopyservice,youcanquicklybackuporrestoreExchangedatabasesofanysize,from100 GBtoseveralterabytes.Youcanalsosetupclustersthatexistindifferentphysicallocations.Allofthesefeaturesprovideimprovedservicelevelsthanmayhavebeenpreviouslypossible.

NetworkandHardwareCostConstraints

FinancialconstraintssurroundingupgradestotheexistingnetworkandhardwaredirectlyaffectthedesignofyourExchangemessagingsystem.Dependingontheintegrityofyourexistingnetwork,certainupgradesmaybenecessarytomeetbusinessanduserrequirements.Incaseswhereupgradepossibilitiesarelimited,youmayormaynotbeabletotakeadvantageofcertainmessagingfeatures,suchasRPCoverHTTPinExchange 2003.Thisfeaturecanhelpyouprovideabettermessagingexperienceoverexistinglow-speed,unreliablenetworkconnections.

Ifitispartofyourbusinessstrategytoreducetotalcostofownershipbyconsolidatingorcentralizingserverhardware,certainfeaturesinExchange 2003,WindowsServer 2003,andOutlook 2003canhelpfacilitatethisstrategy.Forexample,Exchange 2003islesssubjecttomemoryfragmentation,whichmeansthatExchange 2003serverswithfastprocessorscanhandlemoreusersperserverbeforereachingamemoryfragmentationlimit.ThisisalsothecasewithWindowsServer 2003,whichmanagesmemorybettersoyoucanhostmoreusersonaserverbeforeyouencountermemoryfragmentationissues.BettermemorymanagementdoesnotnecessarilymeanthatyouwillseesignificantgainsinCPUperformanceorscalability,butusuallyyoucanhostmoreusersonaserver.

Formoreinformationaboutnewfeatures,see"UnderstandingVersionsofExchange,Windows,andOutlook."

SoftwareCostConstraints

Aswithnetworkandhardwareupgrades,financialconstraintssurroundingupgradestooperatingsystems,serverapplications,andapplicationsforclientcomputersdirectlyaffectthedesignofyourExchangemessagingsystem.Forexample,ifyoucanupgradeyourclientcomputerstoOutlook 2003,theCachedExchangeModefeatureprovidesabetterexperienceoversloworlowbandwidthnetworkconnections.

AdministrativeRequirements

Yourcompany'sadministrativerequirementshaveasignificantimpactonsystemdesign,especiallyifyouwanttoreduceadministrativecostsbymovingtowardamorecentralizedmodel.

Businessesusuallyimplementadministrativemodelsthatgenerallyfallintotwocategories:

•

Centralizedmanagement   AsinglegroupmaintainscompletecontroloftheExchangesystem.Withthismodel,youimplementasmallnumberofadministrativegroups,whetheryouhaveasingledatacenteroralargenumberofbranchoffices.Asingleinformationtechnologygroupperformsalladministrativetasks.Thismodelistypicalinsmall-ormedium-sizedcompanies,butcanalsobeusedinlargercompaniesthathavehighbandwidthconnectivitybetweenallregionaloffices.

•

Distributedmanagement   CompletecontrolovermanagementoftheExchangesystemisdistributedtocompanyregionsordivisions.Thecompanymightcreateatleastoneadministrativegroupforeachregionordivision,witheachadministrativegroupcontainingroutinggroups,policies,servers,publicfolderdirectoryhierarchies,andotherobjectsspecifictoeachdivision.Acentralinformationtechnologygroupmayberesponsibleformanagingstandardsand