计算机专业外文翻译教学文稿.docx

计算机专业外文翻译教学文稿.docx

《计算机专业外文翻译教学文稿.docx》由会员分享，可在线阅读，更多相关《计算机专业外文翻译教学文稿.docx（21页珍藏版）》请在冰点文库上搜索。

计算机专业外文翻译教学文稿

计算机专业外文翻译

HowtotroubleshootconnectivityissuesinSQLServer2000

ChrisTull,MicrosoftHelpandSupport

ThisarticlecanhelpyoutoresolveconnectivityproblemswithMicrosoftSQLServer2000.Thisarticlecontainsdescriptionsofcommonconnectivityproblemsandthestepsthatyoucantaketohelpresolveyourconnectivityproblems.

SQLServer2000supportsseveralmethodsofcommunicationbetweentheinstanceofSQLServerandtheclientapplications.IfyourclientapplicationandtheinstanceofSQLServerresideonthesamecomputer,MicrosoftWindowsinterprocesscommunication（IPC）components,suchaslocalnamedpipesortheSharedMemoryprotocol,areusedtocommunicate.However,whentheclientapplicationandtheinstanceofSQLServerresideondifferentcomputers,anetworkIPC,suchasTCP/IPornamedpipes,isusedtocommunicate.

SQLServer2000usesNet-Library,aDLL,tocommunicatewithaparticularnetworkprotocol.AmatchingpairofNet-Librariesmustbeactiveontheclientcomputerandtheservercomputertosupportthenetworkprotocolthatyouwanttouse.Forexample,ifyouwanttoenableaclientapplicationtocommunicatewithaspecificinstanceofSQLServeracrossTCP/IP,theclientTCP/IPSocketsNet-Library（Dbnetlib.dll）mustbeconfiguredtoconnecttotheserverontheclientcomputer.Likewise,theserverTCP/IPSocketsNet-Library（Ssnetlib.dll）mustlistenontheservercomputer.Inthisscenario,theTCP/IPprotocolstackmustbeinstalledonboththeclientcomputerandtheservercomputer.

AfteryouinstallSQLServer2000,youcanconfigurethepropertiesoftheclientNet-LibrariesbyusingClientNetworkUtility.YoucanconfigurethepropertiesoftheserverNet-LibrariesbyusingServerNetworkUtility（Svrnetcn.exe）.TheserverNet-LibrariesareinstalledduringtheinstallationoftheservertoolsinSQLServerSetup.However,someoftheserverNet-Librariesmaynotbeactive.Bydefault,SQLServer2000enablesandlistensonTCP/IP,namedpipes,andSharedMemory.Therefore,foraclienttoconnecttoaservercomputer,theclientmustconnectbyusingaclientNet-LibrarythatmatchesoneoftheserverNet-LibrariesthatiscurrentlybeingusedbytheinstanceofSQLServer.

ForadditionalinformationaboutSQLServercommunicationcomponentsandNet-Libraries,seethefollowingtopicsinSQLServerBooksOnline:

•CommunicationComponents

•ClientandServerNet-Libraries

•ManagingClients

Troubleshootconnectivityissues

MostoftheconnectivityissuesthatyoumaynoticeinSQLServer2000occurbecauseofproblemswithTCP/IP,Windowsauthentication,oracombinationofTCP/IPandWindowsauthentication.

ImportantBeforeyoustarttotroubleshootconnectivityissuesinSQLServer2000,makesurethattheMSSQLServerserviceisstartedonthecomputerthatisrunningSQLServer.

VerifyyourDNSsettings

ThenameresolutionprocessinDomainNameSystem（DNS）isusedtoresolvetheIPaddresstothenameoftheinstanceofSQLServer.Ifthenameresolutionprocessdoesnotworkcorrectly,theinstanceofSQLServerisnotreachable,andyoumayreceiveoneormoreofthefollowingerrormessages:

SQLServerdoesnotexistoraccessdenied

GeneralNetworkError

CannotGenerateSSPIContext

Toverifythatthenameresolutionprocessisresolvingthecorrectserver,youcanpingtheserverbyusingtheservernameandtheIPaddressoftheserver.Todoso,followthesesteps:

1.ClickStart,andthenclickRun.

2.IntheRundialogbox,typecmdintheOpenbox,andthenclickOK.

3.Atthecommandprompt,runthefollowingcommand:

ping

NotetheIPaddressthatisreturned.

4.Atthecommandprompt,runthefollowingcommand（whereIPaddressistheIPaddressthatyounotedinstep3）:

ping–a

Verifythatthecommandresolvestothecorrectservername.Ifeitherofthespecifiedcommandsarenotsuccessful,timeout,ordonotreturnthecorrectvalues,theDNSlookupisnotworkingcorrectlyortheproblemoccursbecauseofothernetworkingorroutingissues.ToseeyourcurrentDNSsettings,runthefollowingcommandatacommandprompt:

ipconfig/all

Toworkaroundthisproblem,addanentryfortheservertothe%systemroot%\system32\drivers\etc\hostsfileontheclientcomputer.YoucanalsoworkaroundtheproblembyconnectingtotheserverbyusingtheNamedPipesNet-library.

Verifytheenabledprotocolsandaliases

Connectivityproblemsmayoccurifthealiasontheclientcomputerissetincorrectly.YoucanviewthealiasesbyusingClientNetworkUtility.Todoso,followthesesteps:

1.StartClientNetworkUtility.IftheSQLServerclienttoolsareinstalledonthecomputerthatisrunningtheclientapplication,followthesestepstostartClientNetworkUtility:

a.ClickStart,andthenpointtoPrograms.

b.PointtoMicrosoftSQLServer,andthenclickClientNetworkUtility.

IftheSQLServerclienttoolsarenotinstalledontheclientcomputer,followthesestepstostartClientNetworkUtility:

a.ClickStart,andthenclickRun.

b.IntheRundialogbox,typecliconfgintheOpenbox,andthenclickOK.

2.IntheSQLServerClientNetworkUtilitywindow,clicktheGeneraltab,andthenenablealltheprotocolsthatyouwanttouse.

NoteYoumustatleastenabletheTCP/IPprotocolandthenamedpipesprotocol.

3.ClicktheAliastab,andthenverifythealiasesthatareconfiguredfortheinstanceofSQLServer.

4.VerifythepropertiesofthealiasestomakesurethattheservernameorIPaddressandtheprotocolareconfiguredcorrectly.

Youcancreateanewaliastotesttheconnectivitybyusingtheservername,theIPaddress,orevenbyusingadifferentprotocol.

NoteEarlierversionsofMicrosoftDataAccessComponents（MDAC）haveadifferentuserinterfaceforClientNetworkUtility.Therefore,ifyoudonotseetheoptionsthatarelistedinthisarticle,installalaterversionofMDAConthecomputerthatisrunningtheclientapplication.

VerifythattheinstanceofSQLServerislisteningcorrectly

ToverifythattheinstanceofSQLServerislisteningonnamedpipes,TCP/IP,oranotherprotocolthatyouareusingattheclientapplication,openthecurrentSQLServererrorlogfile.TheSQLServererrorlogfilemaycontainentriesthataresimilartothefollowing:

2003-11-0609:

49:

36.17serverSQLserverlisteningonTCP,SharedMemory,NamedPipes.2003-11-0609:

49:

36.17serverSQLserverlisteningon192.168.1.5:

1433,127.0.0.1:

1433.

IfyouanalyzetheentriesintheSQLServererrorlogfile,youcanverifythattheinstanceofSQLServerislisteningonthecorrectIPaddressandonthecorrectport.Bydefault,adefaultinstanceofSQLServerlistensontheport1433.YoucanalsouseServerNetworkUtilitytoverifytheprotocolsettingsforSQLServerandtochangethepropertiesinSQLServer,includingtheprotocolsthatcanconnecttoSQLServerandtheportsthatcanbeused.FormoreinformationaboutusingServerNetworkUtility,seethe"SQLServerNetworkUtility"topicinSQLServerBooksOnline.

Sometimes,SQLServer2000maynotbindtoport1433oranyotherspecifiedport.ThisproblemmayoccuriftheportisbeingusedbyanotherapplicationorifyouaretryingtoconnectbyusinganIPaddressthatisnotcorrect.Therefore,theTCP/IPconnectionstoSQLServermaynotbesuccessfulandyoumayreceivethefollowingerrormessageintheSQLServererrorlogfile:

2001-11-1415:

49:

14.12serverSuperSocketInfo:

BindfailedonTCPport1433.

IfyoucannotconnecttotheinstanceofSQLServerbyusingaTCP/IPconnection,trytousethenamedpipesprotocolortheSharedMemoryprotocol.Runthefollowingcommandatacommandprompttoobtaininformationabouttheportsthatareinuse:

NETSTAT–an

YoucanalsousethePortqrycommand-lineutilitytoobtainmoreinformationabouttheportsthatareinuse.

NoteFornamedinstancesofSQLServer,SQLServerdynamicallydeterminestheportandlistensonthedeterminedport.Therefore,whenyoustartthenamedinstanceofSQLServer,SQLServertriestolistenontheportthatwaspreviouslybeingused.IfSQLServercannotbindtothatport,thenamedinstancemaydynamicallybindtoadifferentport.Inthatsituation,makesurethattheclientapplicationisalsosettodeterminetheportdynamically.Alternatively,youcanalsospecifyastaticportforthenamedinstancetobindtoandtolistenonbyusingClientNetworkUtility.

TroubleshootMDACIssues

ConnectivityproblemsmayalsooccurbecauseofproblemswithMDAC.Forexample,asoftwareinstallationmayoverwritesomeoftheMDACfilesorchangethepermissionsthatyoumusthavetoaccesstheMDACfiles.YoucanruntheMDACComponentCheckertoverifytheMDACinstallationonyourcomputer.

NoteIfyouareconnectingtoanamedinstanceofSQLServer,makesurethatyouarerunningMDAC2.6orlateronyourcomputer.EarlierversionsofMDACdonotrecognizenamedinstancesofSQLServer.Therefore,connectionstonamedinstancesmaynotbesuccessful.

YoucanusetheOdbcping.exeutilitytoverifyconnectionsthroughtheSQLServerODBCdriver.

YoucanalsotestconnectivitytotheinstanceofSQLServerbyusinga.udlfile.

Troubleshootfirewallissues

IffirewallexistsbetweentheclientcomputerandthecomputerthatisrunningSQLServer,makesurethattheportsthatarerequiredtocommunicatethroughthefirewallareopen.

IfyouusetheTCP/IPprotocoltoconnecttotheinstanceofSQLServer,makesurethatyoucanusetheTelnetprogramtoconnecttotheportwhereSQLServerislistening.TousetheTelnetprogram,runthefollowingcommandatacommandprompt:

Telnet

IftheTelnetprogramisnotsuccess