第1題Usethels-lcommandtolistthefollowingfilelist,whichfileisasymboliclinkfileA-rw-rw-rw-2stustu56Sep0911:02-02file01B-rwxrwxrwx2stustu56Sep0911:02-02file02Cdrwxr--r--1stustu1024Sep1008:10file03Dlrwxr--r--1stustu2024Sep1208:12file04第2題Whenyouenterapartofthecommandatthebackofthecommandprompt,pressthe(__)key,andLinuxwillhelpyoutypetheremainingcharactersandsupplementthemintoacompletecommand.Iftherearemultiplematchingcommands,double-click(__)key,Linuxwilldisplayallmatchingcommands.ATABBCONTRLCSHIFTDSPACE第3題WhatisthedefaultSHELLinCentOS?AbashBkshCtcshDsh第4題MayIaskwhichoptionisthewrongdescriptionoftheLinuxkernel.AThekernelistheheartofLinux,whichrealizesthebasicfunctionsoftheoperatingsystemBKernelfunctionsincludecontrollinghardwaredevicesandprovidinghardwareinterfacesCOrdinaryuserscandirectlyinteractwiththekernelDTheLinuxkernelwasinitiallydevelopedbyLinunsTorvalds第5題Theso-calledcommand(Command)inLinuxbroadlyincludes:AexecutablebinaryBexecutablelibraryfileCshellscriptfileDshellbuilt-infunctions正確答案：ACD第6題WhichofthefollowingstatementsaboutcancelingtheshutdowncommandinCentOSiscorrect?AYoucancanceltheshutdowncommandbypressingthectrlandzkeys.BYoucancanceltheshutdowncommandwithshutdown-cCShutdowncommandisirreversibleDBydefaultonlytherootusercancanceltheshutdowncommand正確答案：BD第7題RegardingtheShellinLinux,whichofthefollowingstatementsiscorrect?AShellisakindofsoftwarethatcanfacilitateyouto"talk"withtheLinuxsystem.BOutputsfromawidevarietyofsystemscanbeprocessed.CTheinterfaceprogrambetweentheuserandtheLinuxkernel.DAprogramminglanguagesimilartoC.正確答案：ABC第8題WhichofthefollowingstatementsarefalseaboutcommandsinLinux?ACommandsreferspecificallytobinaryexecutablesinthesystem.BCommandstakeparametersCCommandoptionscanbethoughtofasaswitchthatcontrolsthebehaviorofthecommandDCommandoptionsgenerallystartwitha"--"or"-"symbol正確答案：AB第9題InLinux,whatinformationcanthecommandpromptafteropeningBASHtellyouaboutthehost?AloginhostnameBloginusernameCThecurrentworkingdirectoryoftheuserDUserlastlogintime正確答案：ABC第10題ThetwomostbasicpartitionsrequiredtoinstallLinuxare()and().A/bootpartitionB/homepartitionCrootpartitionDSwappartition正確答案：CD第11題WhichofthefollowingstatementsaretrueaboutCentOS?ACentOS100%compatiblewithRedHatEnterpriseEdition(RHEL)BCentOSdoesnotprovidededicatedtechnicalsupportanddoesnotcontainclosedsourcesoftwareCCentOS64-bitversioncanbeinstalledona32-bitarchitecturemachineDCentOSisrecompiledfromthesourcecodeofRedHatEnterpriseEdition(RHEL)正確答案：ABD第1題Regardingthemodeofvi,whichofthefollowingstatementsarecorrect?AvihasfourbasicmodesBInthecommandlinemodeofvi,youcaninputactioncommands,suchasmovingthecursor,deleting,copying,pasting,etc.CIntheinputmodeofvi,youcanentercharactersDIntheinputmode,presstheESCkeytoenterthegeneralmodeEPressthe:signinthenormalmodetoenterthecommandlinemode正確答案：CDE第2題Regardingtheactioninstructionsinvi,whichofthefollowingstatementsarecorrect?ATheddcommandmeanstodeletethelinewherethecursorislocatedBThexcommandmeanstodeletethepreviouscharacterwherethecursorislocatedCTheucommandcanundotheoperationDctrl+rcanresumeoperationEAlloftheabovecommandsneedtobeenteredincommandlinemode正確答案：ACD第3題Onvi,thefollowingstatementsarewrong?Avicomespre-installedinalmostallLinuxdistributionsBThemostcompactversionofviisasmallversionofviCviisrichinfunctionsandextremelyefficientDvimisanimprovedversionofvi,perfectlyforwardcompatiblewithvi第4題Whichofthefollowingcommandsindicatesthatviisforcedtoexitwithoutsaving.A:wqB:qC:q!D:!q第5題Movetoline15,copy10linesdown,movetotheendofthetext,paste,whichofthefollowingiscorrect?A15G;10yy;G;pB15$;10y;G;pC15g;10y;$;pD15$;10p;G;y第6題Movedown10linesandlocatetotheendoftheline,whichofthefollowingiscorrect?A10$B10ddC10jD10kManagingfiles-part1(listing,manipulatingfiles)第1題Ifwesaythatafilehasapermissionof541,whatdoesitmean?AReadable,non-writable,andexecutableforthefileowner,readable,non-writable,andexecutableforusersinthesubordinateusergroup,unreadable,non-writable,andexecutableforotherusersBReadable,writableandexecutableforthefileowner,readable,non-writableandexecutableforusersinthesubordinateusergroup,unreadable,writableandnon-executableforotherusersCReadable,writableandexecutableforthefileowner,readable,writableandnon-executableforusersinthesubordinateusergroup,unreadable,writableandnon-executableforotherusersDReadable,writable,andexecutableforthefileowner,unreadable,writable,andexecutableforusersinthesubordinateusergroup,unreadable,writable,andexecutableforotherusers第2題Regardingthemvcommand,whichusagesareachievable?Amv/tmp/file01~canmovethefile01fileinthetmpdirectorytothecurrentuser'shomedirectory.Bmv./file01./file02canrenamethefile01fileinthecurrentworkingdirectorytofile02.Cmv-R~/sampledir.Youcanmovethesampledirdirectoryunderthehomedirectorytothecurrentworkingdirectory.Dmv-f./file01~canmovethefile01fileinthecurrentdirectorytothecurrentuser'shomedirectoryandoverwritethefilewiththesamename.正確答案：ABD第3題Withregardtothecpcommand,whichusesareachievable?Acp-R~/sampledir.Youcancopythesampledirdirectoryunderthecurrentuser'shomedirectorytothecurrentdirectory.Bcp./file01./file02..cancopythefile01fileinthecurrentdirectorytothecurrentdirectoryandrenameittofile02,andcopythefile01filetotheupperdirectoryofthecurrentdirectory.Ccp/home/stu/file01~/rootcancopythefile01directorytotherootuser'shomedirectoryDcp-R../sampledir~rootcancopythesampledirdirectoryintheupperdirectorytotherootuser'shomedirectory正確答案：AD第4題Whichstatementsarecorrectaboutthecpcommand?AThecpcommandcancopymultiplefilesatthesametimeBBydefault,whenthecpcommandencountersafilewiththesamenamewhencopying,itwillbeautomaticallyoverwrittenCBydefault,thecpcommandwillcopythefileattributestogetherDThecpcommandcancopyandrenamefilesatthesametime正確答案：AD第5題WhatstatementsarewrongaboutfilepermissionsinLinux?AFilepermissionsarechangedaccordingtodifferentusersBForafile,userscanbedividedintofileownerandotherusersCFileownerscanhavemultipleDInallcases,thefileownerhasfullpermissionsonthefile正確答案：BCD第6題Ifyouusethels-lcommandtolistfiles,thefirstfieldofthefileis-rwxr-x,thethirdfieldisstu,andthefourthfieldissgroup,thenthefollowingstatementsarewrongAUsersinthesgroupcanmodifythisfileBThestuusercanexecutethisfileCUsersexceptthefileownerandsubordinategroupuserscanreadthisfileDUsersinthesgroupcanexecutethisfile正確答案：AC第7題Ifyouusethels-lcommandtolistfiles,thefirstfieldofthefileisdrwxr-x,whatdoesitmeanAThisisasymboliclinkfile,whichisreadable,writable,andexecutableforthefileowner,readable,non-writable,andexecutableforusersinthesubordinateusergroup,andunreadable,writable,andexecutableforotherusersBThisisanordinaryfile,whichisreadable,writable,andexecutablebythefileowner,readable,non-writable,andexecutablebyotherusers,andunreadable,writable,andexecutablebyusersinthesubordinateusergroup.CThisisadirectoryfile,whichisreadable,writable,andexecutableforthefileowner,readable,non-writable,andexecutableforusersinthesubordinateusergroup,andunreadable,non-writable,andnon-executableforotherusers.DThisisadirectoryfile,whichisreadable,writable,andexecutableforthefileowner,readable,writable,andexecutableforusersinthesubordinateusergroup,andunreadable,writable,andexecutableforotherusers.第8題Regardingthecatcommand,whichofthefollowingdescriptionsarecorrect?AThecatcommandcanbeusedtomergemultipletextfilesBThecatcommandcanmarkthetextwithlinenumberswhenoutputtingtextCSuitableforviewingtextfilesofanysizeDUsetheupanddownarrowkeystoscrollthroughthefilecontents正確答案：AB第9題Regardingthelesscommand,whichofthefollowingdescriptionsarecorrect?AThelesscommanddoesnotoutputthecontentofthetextfiledirectlytothecommandlineBYoucanusetheupanddownarrowkeystopageupanddownCThelesscommandcanbesaidtouse":keyword"tofindaspecificstringinatextfileDUsectrl+Xtoexitless第10題Regardingthetailandheadcommands,whichofthefollowingdescriptionsarecorrect.Aheaddisplaysthefirst5linesofthefilebydefaultBtailcanonlyviewonetextfileatatimeCThispairofcommandsisoftenusedtoviewlogfilesDYoucanusethe-noption(nisanaturalnumber)tospecifythenumberoflinestobedisplayedbytailandhead正確答案：CD第11題RegardingwildcardsinLinux,whichofthefollowingdescriptionsarecorrect?AWildcardscanbeusedtooperateonbatchfilesB*canmatchanysinglecharacterC[0-9]canmatchanysinglecharacterbetween0and9D[!A-Z]canmatchanysinglecharacterexceptuppercaseAtoZ正確答案：ACD第12題Nowyouneedtofindallthefilesnamedtempintherootdirectory,andthendeletethem.Youdon’tneedtobepromptedwhendeletingthem.HowcanIdothis?Afind/-nametemprm*BWriteashellscripttoachieveCfind/-nametemp–execrm{}\;Dfind/-nametemp–execrm第13題Thefollowingcommandscanreplacealllowercasetsinthetextfilenamedfile.txtinthecurrentdirectorywithuppercaseTs.Atr't''T'file.txtBtr't''T'file.txtCcut't''T'file.txtDcut't''T'file.txt第14題Nowchangethepermissionofthewwwfileinthe/directorytoonlythemainuserhastheexecutionpermission,andnooneelsehasanypermission.WhatshouldIdo?Achmod100/wwwBchmod001/wwwCchmod700/wwwDchmod007/www第15題Regardingabsolutepathsandrelativepaths,whichofthefollowingstatementsareincorrect?A/etc/sysconfig/network-scripts/ifcfg-eth0isarelativepathB./file01isarelativepathCTheword"relative"intherelativepathreferstorelativetothecurrentworkingdirectoryDmnt/myworkisarelativepath正確答案：ABManagingfiles-part2(archiving,compressingfiles,linkingfiles,viewingtextfiles,findingfiles)第1題Regardingthegzipcommand,whichofthefollowingpracticescanachievethegoal?Atar-czftmpdir.gz./tmpdircancompressthetmpdirdirectoryunderthecurrentdirectoryintoacompressedfilenamedtmpdir.gz.Bgzip-9./file01cancompressfile01withthehighestcompressionratio.Cgzip-d./file.gzcandecompressthefile.gzcompressedfiletothecurrentdirectory.Dgzip./file01./file02cancompressthefile01andfile02filesinthecurrentdirectoryintocompressedfilesnamedfile01.gzandfile02.gzrespectively.正確答案：CD第2題Regardingthejointuseoftarandgzip,whichofthefollowingdescriptionsarecorrect?Atar-czftmp.tar.gz./file01./file02canpackandcompressthefile01andfile02filesinthecurrentdirectoryintoafilenamedtmp.tar.gzBtar-cdftmp.tar.gzcandecompressandunpackthetmp.tar.gzcompressedfileinthecurrentdirectorytothecurrentdirectoryCThesuffixofthefilecompressedwithtar-czfmustbetar.gzDtar-czfsampledir.tar.gz./sampledircanpackandcompressthesampledirdirectoryunderthecurrentdirectoryintoafilenamedsampledir.tar.gz正確答案：AD第3題Whichofthefollowingstatementsaretrueaboutsymboliclinks?ASourcefilescanberead,written,andexecutedthroughsymboliclinkfiles.BThesymboliclinkfileandthesourcefileareactuallythesamefile.CDeletethesourcefile,thesymlinkfilewillbecomeunusableDCannotcreatesymboliclinkagainforsymboliclinkfile正確答案：AC第4題Regardingtherelationshipbetweenfilehardlinksandsourcefiles,whichofthefollowingdescriptionsarecorrect?AFilehardlinksandsourcefilesactuallyshareafilecontentdataBSourcefiledeletionhasnoeffectonfilehardlinksCAhardlinktoafileononeharddiskpartitioncanbelocatedonanotherpartitionDChangestothehardlinkcontentofthefilewillnotaffectthesourcefile正確答案：AB第5題Regardinghardlinks,whichofthefollowingstatementsarecorrect?ACannotspanfilesystems.BlinktodirectoryCTheinode-numberofthehardlinkfileisthesameastheinode-numberofthelinkedfileDTheprinciplesofhardlinksandsymboliclinksareactuallythesame正確答案：AC第6題WhatstatementsarewrongaboutfilepermissionsinLinux?AFilepermissionsarechangedaccordingtodifferentusersBForafile,userscanbedividedintofileownerandotherusersCFileownerscanhavemultipleDInallcases,thefileownerhasfullpermissionsonthefile正確答案：BCD第7題Regardingthelocatecommand,whichofthefollowingdescriptionsarecorrect?AThelocatecommandcanquicklyfindfilesBIfyoudonotspecifythesearchdirectoryrange,locatewillusethecurrentworkingdirectoryasthesearchrangeCThelocatelookupisfasterbecauseitusesamoreefficientlookupalgorithmDlocatesometimeshastheproblemthatthenewfilecannotbefoundElocatesometimesfindstheproblemoffindingdeletedfiles正確答案：ADE第8題Nowyouneedtofindallthefilesnamedtempintherootdirectory,andthendeletethem.Youdon’tneedtobepromptedwhendeletingthem.HowcanIdothis?Afind/-nametemprm*BWriteashellscripttoachieveCfind/-nametemp–execrm{}\;Dfind/-nametemp–execrm第9題Howtofindthefilesinthe/tmpdirectorygeneratedinthepast24hours,thesizeisgreaterthan5k,andthesuffixis??tmp,anddeletethemwithoutprompting.Afind/tmp–typef?a?ctime?1?a?size+5k-execrm{}\;Bfind/tmp–typef?a?mtime?1?a?size+5k-execrm-f{}\;Cfind/tmp–typef?a?ctime?1?a?size?5k-execrm-r{}\;Dfind/tmp–typef?a?mtime?1?a?size+5k-execrm{}\;第10題Regardingfilepackaging(archiving),whichofthefollowingstatementsarecorrect?AtarcanpackentiredirectoriesBThepackagedfilesizeaftertarpacksmultiplefilesisslightlysmallerthanthesumoftheoriginalfilesizesCThetarpackagefilemusthavea.tarsuffixDYoucanusethetarcommandtomergetwopackagedfilesEYoucanusethetarcommandtoviewthefilesinthepackagedfile正確答案：ADE第11題Regardingthetarcommand,whichofthefollowingpracticescanachievethegoal?Atar-cftmp.tar./file01./file02canpackthefile01andfile02filesinthecurrentdirectoryintothetmp.tarfile.Btar-Af./tmp.tar./tmp01.tarcanmergethetmp.tarfileintotmp01.tar.Ctar-xf./tmp.tar-C~canunpackthetmp.tarpackagefiletothecurrentuser'shomedirectory.Dtar-f./tmp.tar-rfile01candeletethefile01fileinthetmp.tarpackagefile.正確答案：AC第12題Whichofthefollowingstatementsaboutfilecompressionarecorrect?ATherearemanytoolsavailableforcompressingfilesinLinux.BAftercompressingafilewiththegzipcommand,thesourcefilewillbedeletedbydefaultCThegzipcommandcanadjusttheratiooffilecompression.DThedefaultextensionofgzipcompressedfilesis.gzEGzipwilldeletethecompressedfilebydefaultwhendecompressingthefile正確答案：ABCDERedirectionandpipes第1題Regardingthetailandheadcommands,whichofthefollowingdescriptionsarecorrect.Aheaddisplaysthefirst5linesofthefilebydefaultBtailcanonlyviewonetextfileatatimeCThispairofcommandsisoftenusedtoviewlogfilesDYoucanusethe-noption(nisanaturalnumber)tospecifythenumberoflinestobedisplayedbytailandhead正確答案：CD第2題RegardingpipesinLinux,whichofthefollowingdescriptionsarecorrect?APipelineisaspecialkindofinputandoutputredirectionBItistoredirectthestandardoutputofonecommandtothestandardinputofanothercommandCCompletingcomplextasksoftenrequiresconstructingcommandpipelinesDAllcommandscanbeusedtoconstructpipelines正確答案：ABC第3題Regardingthecommandecho-e"1apple\n2pear\n3banana">>fruit.txt,whichofthefollowingdescriptionsarewrong.AThiscommandredirectstheoutputofechotothefruit.txtfile.BIftheoriginalcontentinthefruit.txtfilewillbeoverwrittenCTheoutputredirectionofechowillbeappendedtotheendofthefruit.txtfileDThecommandwillerrorifthefruitfiledoesnotexist正確答案：BD第4題RegardinginputandoutputredirectioninLinux,whichofthefollowingdescriptionsarecorrect?AThestandardoutputstream(stdout),displaysoutputfromthecommand,filedescriptoris0BStandardinputstream(stdin),whichprovidesinputtothecommand,filedescriptoris1CForanylinuxcommand,theresultisoutputtotheoutputdevicethroughstdout;DLinuxuses>and>>operatorstoredirectstandardoutputEStandardinputredirectionistoletthecommandgetinputfromthespecifiedfileinsteadofstdin.正確答案：DE第5題Whichofthefollowingstatementsisincorrect?sort-k3<002ZhangSan5500>005LeeSi6600>009WangWu5120>EOFAThiscommandusestheHereDocumentfeatureofinputredirectionBEOFisthedelimiteroftheinputfileandisfixedCTheoutputofthiscommandwillsorttheinputbyfieldthreeDThedelimiterEOFmustbewrittenatthetop.Therecannotbeanycharactersinfrontofit,andtherecannotbeanycharactersbehindit.第6題Howtoredirectthestandardoutputofthels-lfile01file02commandtoafilenamedstdout.txtandignoretheerroroutput.Als-lfile01file021>stdout.txt2>/dev/zerosBls-lfile01file02&>stdout.txt2>/dev/nullCls-lfile01file02&>stdout.txt2>dev/nulDls-lfile01file022>dev/null1>stderr.txtManagingusers第1題Whichcommandshouldbeusedtochangethesubordinategroupofthefilesamplefileinthecurrentdirectorytothestuusergroup?Achmodstu./samplefileBchownstu./samplefileCchown:stu./samplefileDchmod:stu./samplefile第2題Ifwesaythatafilehasapermissionof541,whatdoesitmean?AReadable,non-writable,andexecutableforthefileowner,readable,non-writable,andexecutableforusersinthesubordinateusergroup,unreadable,non-writable,andexecutableforotherusersBReadable,writableandexecutableforthefileowner,readable,non-writableandexecutableforusersinthesubordinateusergroup,unreadable,writableandnon-executableforotherusersCReadable,writableandexecutableforthefileowner,readable,writableandnon-executableforusersinthesubordinateusergroup,unreadable,writableandnon-executableforotherusersDReadable,writable,andexecutableforthefileowner,unreadable,writable,andexecutableforusersinthesubordinateusergroup,unreadable,writable,andexecutableforotherusers第3題Whenloggingintothesystemasuserrootandusingthermcommandtodeletefiles,whichofthefollowingpracticesarecorrect?Arm./sampledircandeletethesampledirdirectoryunderthecurrentdirectoryBrm-f./file01candeletethefile01fileinthecurrentdirectory,andwillconfirmwiththeuserbeforedeleting.Crm-R./sampledircandeletethesampledirdirectoryinthecurrentdirectoryDrmfile01file02candeletethefile01andfile02filesinthecurrentworkingdirectory,andwillconfirmwiththeuserbeforedeleting.正確答案：CD第4題WhatstatementsarewrongaboutfilepermissionsinLinux?AFilepermissionsarechangedaccordingtodifferentusersBForafile,userscanbedividedintofileownerandotherusersCFileownerscanhavemultipleDInallcases,thefileownerhasfullpermissionsonthefile正確答案：BCD第5題Ifyouusethels-lcommandtolistfiles,thefirstfieldofthefileis-rwxr-x,thethirdfieldisstu,andthefourthfieldissgroup,thenthefollowingstatementsarewrongAUsersinthesgroupcanmodifythisfileBThestuusercanexecutethisfileCUsersexceptthefileownerandsubordinategroupuserscanreadthisfileDUsersinthesgroupcanexecutethisfile正確答案：AC第6題RegardingtheusermodcommandinCentOS,thefollowingdescriptioniscorrect:AWhenmodifyingtheuser'sUIDwiththe-uoption,youmustensurethatthisUIDhasnotbeenusedbyothersBWhenusing-Gtomodifytheuser'ssubordinateusergroup,iftheusergroupdoesnotexist,LinuxwillautomaticallycreatethisusergroupCWhentheuserhasloggedintothesystem,theuser'sUIDcannotbemodifiedDInthecasethattheuserhasloggedintothesystem,youcanusethe-loptiontomodifytheuser'susernameEWhenmodifyingtheuser'shomedirectorywiththe-doption,youmustensurethatthedirectorytobespecifiedalreadyexists正確答案：ACE第7題Regardingtheswitchusercommandsu,thefollowingdescriptioniscorrect:AUserpasswordisrequiredwhenswitchingfromrootusertocommonuserBTheuserpasswordisrequiredwhenswitchingfromanormalusertotherootuserCWhenswitchingbetweenordinaryusers,userpasswordsarerequiredDUserpasswordisrequiredwhenswitchingfromrootusertovirtualuserEAfterswitchinguseridentities,theaccessrightstothesystemalsochange正確答案：BCE第8題Assumingthatwelogintothesystemasusernboocer,weareinthehomedirectoryofusernboocer,andnowwewanttoswitchtouserroot.Thefollowingdescriptioniscorrect:AUsesuroottoswitch,youneedtoentertherootuserpassword,andyouwillbeintherootuser'shomedirectoryafterswitching.BUsesu-roottoswitch,youneedtoentertherootuserpassword,afterswitching,youwillbeintherootuser'shomedirectoryCUsesu-lroottoswitch,youneedtoentertherootuserpassword,afterswitching,youwillbeintherootuser'shomedirectoryDUsesuroottoswitch,youneedtoenterthenbooceruserpassword,afterswitching,itisinthenboocerhomedirectoryEUsesu-roottoswitch,youneedtoenterthenbooceruserpassword,afterswitching,youwillbeintherootuser'shomedirectory正確答案：BC第9題Theuserinformationthatcanbeviewedbythefingercommandis:AUserlastlogintimeBusernameCuserhomedirectoryDUserID正確答案：ABC第10題Theuserinformationthatcanbeviewedbytheidcommandis:Auser'screationtimeBUser'sprimaryusergroupCThenameoftheusergrouptowhichtheuserbelongsDuserhomedirectory正確答案：BC第11題Auser'sprimaryusergroupattributewillaffect:AUser-createdfileattributesBUseraccessrightstofilesCWhethertheuserisavirtualuserDCanusersbedeleted正確答案：AB第12題RegardingusergroupsinLinux,thedescriptioniswrong:ATheidentityoftheusergroupiscalledGIDBAusercanonlybelongtooneusergroupCAusergroupcancontainmultipleusersDAtthesametime,auser'smainusergroupcanonlyhaveoneEEachusermustbelongtoanindependentprivateusergroupwiththesamenameastheuser正確答案：BE第13題RegardingtheuserinCentOS,thedescriptionerroris:AVirtualusersareforguestsofthesystemBTheUIDoftherootuserisfixedCThedefaultshellusedbyvirtualusersisBASHDLinuxidentifiesusersbytheirusernamesEOrdinaryusershaveonlylimitedprivilegesonthesystem正確答案：AC第14題InCentOS,bydefault,theUIDrangesforvirtualusersare:A1-499B0-499C0-500DAfter500第15題ThecommandtodisplaytheIDoftheuserandtheIDoftheusergrouptowhichitbelongsis:AsuBwhoCidDfingers第16題RegardingtheuserconfigurationfileusedinLinux,thefollowingdescriptioniscorrect:A/etc/passwdstorestheuser'sencryptedpasswordB/etc/passwdstorestheuser'smainusergroupinformationCIftheuserpasswordisempty,anexclamationpointwillappearinthesecondfieldof/etc/passwd!oranasterisk*DThelastmodificationtimeofthepasswordrepresentedbythethirdfieldin/etc/shadowEUserattributescanbemodifiedbymodifyingthecontentsofthepasswdandshadowfiles正確答案：BDE第17題RegardingtheusergroupconfigurationfileusedinLinux,thefollowingdescriptioniscorrect:AThe/etc/gshadowfilecanonlybereadandwrittenbytherootuserBThefourthfieldof/etc/groupisempty,whichmeansthatthereisnouserintheusergroupCThereareasmanylinesin/etc/groupasthereareusergroupsinthesystemDWhencustomizingsomepermissionmodelswithcomplexrelationshipstructures,itisnecessarytosetusergrouppasswords正確答案：ACD第18題Whichofthefollowingstatementsaboutthesudocommandiscorrect?ABydefault,alluserscanusethesudocommandBTheconfigurationfileforthesudocommandis/etc/sudoersCBydefault,thereareonlyrootconfigurationsinthesudoersfileDTherootusercanexecuteanycommandasanyuserthroughthesudocommand正確答案：BCD第19題WhichofthefollowingstatementsaboutLinuxsystemusermanagementiswrong?AAsasystemadministratorwhomasterstherootuserpassword,theoreticallyitisbesttohaveonlyoneBToexecuteacommandthatonlyarootuserhaspermissiontoexecute,youmustfirstswitchtotherootuseridentityCSomereasonablerootuser"powers"canbeassignedtoregularusersbysomemeansDTherecanonlybeonerootuserinthesystemETosharerootprivilegeswithsomeoneelse,youneedtotellhimtherootpassword正確答案：BE第20題RegardingthecommandgroupmodformodifyingusergroupsinCentOS,thefollowingdescriptioniscorrect:AChangingtheGIDofausergroupatwillmaycausesystemconfusionBWithoption–nyoucanmodifytheusergroupnameCChangingusergroupnamesmaycausesystemconfusionDIfauserusesacertainusergroupasitsmainusergroup,theusergroupnamecannotbemodifiedaftertheuserhasloggedintothesystem正確答案：AB第21題RegardingthegroupdelcommandinCentOS,thefollowingdescriptioniscorrect:AWhendeletingausergroup,theusersbelongingtotheusergroupwillalsobedeletedBIfauserusesausergroupastheirprimaryusergroup,thenthisusergroupcannotbedeletedCWhendeletingausergroup,theuserswhousethisgroupasthemainusergroupwillbedeletedtogetherDCanonlydeleteemptyusergroupsEWhendeletingausergroup,theusersbelongingtotheusergroupwillstillremain正確答案：BEManagingnetworks第1題Regardingtherelationshipbetweenfilehardlinksandsourcefiles,whichofthefollowingdescriptionsarecorrect?AFilehardlinksandsourcefilesactuallyshareafilecontentdataBSourcefiledeletionhasnoeffe