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Chapter 57. Migration and Integration: NetWare, Unix, and Linux

Chapter 57. Migration and Integration: NetWare, Unix, and Linux

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WhyUseUnixorLinux?

NetWarehasbeenaroundformanyyears,andotherthan

ARCnetitisperhapstheoldestPCnetworkingtechnologystillin

existenceonawidescale.NetWare,however,hasbeen

deployedinlargenetworksthatspangreatgeographical

distances,aswellasinsmalldepartmentalLANsformany

years.Thereexistsalargeuserbaseandasizablepopulationof

trainednetworkadministrators.Manyapplicationshavebeen

developedbyvendorstomakeuseofNovell'sDirectoryService

(NDS,nowtheeDirectory,andreferredtointherestofthis

chapterasdirectoryserviceswhendiscussingNetWare).

However,usingLinuxinaNetWareenvironmenttoprovide

servicestoNetWareclients,toprotectthenetworkthrougha

firewall,ortogivetechnicalusersaLinuxdesktopdoesmake

senseinsomesituations.

OnegoodintegrationscenarioisthesmallLAN.Forexample,

considerasmallcompanythatoriginallycreatedaLANtolink

severalIntel-basedWebserversthatuseaWindowsoperating

system.Businesshasgrownandit'stimetoupgrade.The

choicesaremorepowerfulIntel-basedsystemsrunninga

WindowsvariantorLinuxboxes.Inthiscase,Linuxhasthe

edgebecauseitisnotlimitedtotheIntelplatform.You'llfind

bothUnixandLinuxrunningonmanyhardwareplatforms.

RecentpartnershipsbetweenRedHatandhardware

manufacturersenableLinuxtoscaletolargerenterprise

servers.However,iftheexistingLANusesNetWare(which

meansyouhaveWindowssystemsinyournetwork),

exchanginginformationwithUnixandLinuxServerswillrequire

somenewnetworkingskills.ByusingfastUnix/Linuxboxesto

runyourWebservers,databases(suchasOracle),andother

CPU-intensiveapplications,youcanstillkeepyourWindows

desktopmachines.Novelldoesincorporatetechnology(most

notablyinthe6.xversions)thatgoesalongwaytoward



enablingconnectivitybetweenUnix/LinuxandNetWare.

AnotherreasonyoumightconsiderbringingLinuxintoyour

smallLANisthatit'sbasicallyfree.Youcanbuyinexpensive

versionsfrommanyvendors,suchasSuSE,Caldera,orRed

Hat,thathavesprunguptocatertotheLinuxcommunity,or

youcandownloadaversionfromaWebsite,usuallyfree.If

youhaveanexperiencedUnixstaffatyoursite,Linuxwillbe

muchcheapertoimplementthanNetWare.Withoutthe

experiencedstaff,however,itmightbecomemoreexpensive

whenitcomestosupportandengineering.However,the

variousvendorsjustmentionedalsoprovidesupportfortheir

Linuxversions(alsoknownasdistributions,ordistrosfor

short),andyoucanfindalotofinformationontheInternetby

searchingforUnixorLinux"howto"documents.



Tip

InadditiontoWebresourcesfor"howto"

documents,don'tforgettheman(manual)pages

thatbothUnixandLinuxhave.Forexample,ifyou

gotothehelppageforRedHatLinux,youare

referredtothemanpages,sortedbyfunctions.If

youknowacommandbutneedaquicklookatthe

syntax,youcansimplyenterman.Someof

themanpagesareverytechnicalindetail,butyou

canusuallyfindwhatyouneedquickly.







KeyDifferencesBetweenUnix/Linuxand

NetWare

Themostobviousdifferencethatshouldcometomindwhen

lookingatNetWareandUnix/Linuxisthatthelattersystemsare

computeroperatingsystemsandNetWareisanetwork

operatingsystem.NetWareclientscanincludemanydifferent

platforms,usuallyonesthathavetheirrootsinMS-DOSor

Windowsofsomekind.Yet,nomatteronwhichplatformyou

useNetWare,itbasicallyonlyprovidessupportfornetwork

resourcesharing.YoucanusenativeNetWareservers,oryou

canuseWindowsserversinthesamenetworktooffer

application,print,andotherservicestousers.Authentication

servicesareprovided,asaremechanismsforgrantingor

denyingaccesstodata.Thisisespeciallythecasewhenusing

theeDirectory.Ortheunderlyingserveroperatingsystem(such

asWindows2000ServerorWindowsServer2003)canalsobe

usedtoenforceaccesspermissionsanduserauthentication.



FileSharing

NetWareexcelsatprovidingfileserversonthenetwork.Either

thebindery-basedNetWare3.xorthedirectoryservices

versionscanbeusedtoexerciseagreatdealofcontroloverfile

anddirectoryaccessforoneormoreserversonthenetwork.

Byusingdirectoryservices,youcandistributefilesthroughout

thenetworkonmultipleservers.Clientscanbeauthenticated

bybindery-basedserversordirectoryservicesandaccessthe

resourcestheyneed.Usingabindery-basedsystemofservers

worksbestwhenlocalusersneedaccesstoonlyoneortwo

servers.Inalargernetworkthismightnotbeagoodideaif

resourcesarespreadoutamongmanyservers.Thisisbecause

thebinderyserversrequireauseraccount/passwordoneach



server,andkeepingthesesynchronizedonalotofserverscan

beaheadachefortheuser.Ifyouneedtomanagealarge

numberofservers,whichhasusersneedingresourceson

differentservers,thendirectoryservicesisabetterchoice

becauseitallowstheusertologontothenetworkusing

directoryservicesandgivesmanagementasingleplaceto

manageusersandresources.

UnixandLinuxdonotcomewithfilesharesordirectory

services.Instead,youmustsubstituteNFS,theNetworkFile

System,whichwasoriginallydevelopedbySun.Access

permissionscanbecontrolledusingthestandardmechanisms

providedbyLinux.YoucansetupNFSsothatusersmustlog

ontoeachservertomounttheexportedfilesystem,oryoucan

hidetheauthenticationprocessfromusersbyusingproxy

mechanismsbuiltintomostNFSimplementations.

FormoreinformationaboutNFS,seeChapter31,"FileServer

Protocols."TolearnmoreabouthowLinuxandUnixsystemsuse

resourceaccesspermissions,seeChapter39,"Rightsand

Permissions."



PrinterSharing

NetWareiscapableofprovidingsupportformanykindsof

printingtechnologiesandprotocols,includingthelpr/lpdand

TCPstreamprintingprotocolsusedbyUnixandLinux.Novell

DistributedPrintServicesenablesprintingfromUnixto

NetWare,aswellasfromNetWaretoUnix,byusingageneric

NetWaregateway.Additionally,third-partyprinter

manufacturerscandevelopgatewaysthatcanprovide

additionalfeaturesfortheirprinters.



UserAuthentication

IftheNetWareversionyoucurrentlyemployusesbinderybasedauthenticationservices,youarefamiliarwithhavingto

logontoeachserverwhenyouneedtoaccessaresource.

Similarly,UnixandLinuxuseafilecalled/etc/passwrdthat

residesoneachsystem.Usersmusthaveanentryinthisfile

thatcanbeusedwhentheylogontotheserver.Linuxdoesnot

nativelysupportadirectoryserviceyet(thoughanopensource

directoryserviceisavailableontheWeb),soprovidingasingle

logonforthenetworkwillnotbesomethingyougetoutofthe

box.MostUnixoperatingsystems,however,supportNIS

(NetworkInformationSystem)forsmallLANsorNIS+forlarger

networks.ThissoftwarewasoriginallycalledYellowPages,but

thenamewaschangedtoNISduetotrademarkreasons.NIS

coordinatespasswordandotherinformationonthenetwork

betweenUnixservers.Thereareseveralopen-sourceversions

ofNISthatcanbefoundontheWeb,someofwhichare

intendedforusewithUnix,andothersforLinux.



Note

The/etc/passwrdfileisasimpletextfile,althoughthe

passwordisencryptedforeachuser.Anotherfile,

calledtheshadowpasswordfile,isusuallyemployed

onmodernUnix/Linuxsystemsbecauseallthedata

inthefileisencrypted.Usingthetextversioncan

openuptheentiresystemshouldthefilebecome

availabletoanintruder.







MovingUserAccounts

ToestablishNetWareuseraccountsontheLinuxserver,you

mustmanuallyconfigurethem.Therearenowidelyavailable

utilitiesortoolsyoucanusetoperformthisfunction.However,

thetypicalUnix/Linuxpasswordcanbeusedasareferencefor

thekindofinformationyou'llneedinordertocreateuser

accountsonUnix/Linuxsystems.Ifyouonlyneedtocreatea

fewuseraccountsforsystemadministrators,forexample,the

processwillbesimple.Ifyouneedtocreatealargenumberof

accounts,possiblyforclientworkstations,youprobablywillfind

itnecessarytoproduceareportfromtheNetWaresystemand

usethistomaketheentriesorcreateascriptfilethatcanbe

usedforthispurpose.

TheUnix/LinuxpasswordfileiscoveredinChapter38,"Managing

UnixandLinuxUsers."



AndifyouareusingNetWare5.xor6.x,theNativeFileAccess

PackfeatureenablesUnix,Windows,andMacintoshclientsto

accessNetWareservers.Thisfeaturedoesn'trequireyouto

installNetWareclientsoftwareontheclientsystems,andcan

beintegratedwiththedirectoryservices.

NetWare,particularlythe4.xandhigherversionsthatsupport

directoryservices,keepstrackofalotmoreinformationfora

useraccountthanisdoneonUnix/Linuxsystemsthatusejust

the/etc/passwrdfile.Becauseofthis,andthesimplicityofthe

/etc/passwrdfile,youwon'thavetodoalotofworktocreatenew

useraccountsontheLinuxsystem.However,youmightfind

thatthetrade-offisthatyouneedtoexaminesecurity(file

permissions,forexample)andotheraspectsofyourUnix/Linux



systemtoensurethatyourusersareaffordedthesameaccess.



NetworkingProtocols

TheTCP/IPprotocolisthestandardusedontheInternetand

mostLANs.Ithasbecomeincreasinglypopularforuseinall

kindsofnetworksinjustthepastfewyears.Forexample,early

versionsofWindowsNTwouldinstalltheIPX/SPXprotocolby

default.StartingwithWindowsNT4.0,thedefaultbecame

TCP/IP.ThishasstayedthesameforWindows2000/XPand

WindowsServer2003.

NetWare'slegacyprotocols(IPX/SPX)aren'tusedalot

anymore,sinceNetWareadoptedTCP/IPafewyearsago.

UnlessyouhaveanolderversionofNetWarethatstilluses

IPX/SPX,itwouldbeagoodideatoupgradetheNetWare

serverstoatleastversion5.0,whichdoessupportIP.







Applications

Unfortunately,ifyouhavealargeinvestmentinapplication

softwarethatwaswritten(orcompiled)foraWindowsplatform

orNetWare'snativeservers,youwillneedtopurchasenew

versionsofyourexistingsoftwareorpurchasenewsoftware.If

youhaveinternallydevelopedapplicationsforwhichyouhave

thesourcecode,youmightneedtomakeonlyminorchanges

andrecompilethesourcecodeonaUnix/Linuxsystem.TheC

language(anditsdescendants)istheprogramminglanguageof

choiceforUnix/Linux,soifyourin-houseapplicationswere

writteninC,thistaskmaybesomewhateasier.

Manymajoraswellassecond-tierserverandsystem

manufacturersarenowmarketingsystemsthatincludeLinux.

AsthepopularityofLinuxcontinuestogrow,manyvendors

havestartedtothinkaboutproducingLinuxversionsoftheir

productsaswellasUnixversions.Youwon'tfindMicrosoft

Officethereyet,butyouwillfindcompetingproducts.Ifyou

canusethefileconversioncapabilitiesthatcomewithmost

productsofthistype,youmightfindthatchangingtoanew

productisnotthatpainful,shortofalittleusertraining.

OneofthefactorshelpingtofuelthepopularityofLinuxis

Sun'sStarOffice,anintegratedofficesuitedesignedtoprovide

muchofthefunctionalityofMicrosoftOfficeatafractionofthe

price.Witheachnewrelease(StarOfficeisnowatversion8or

above),compatibilitywithMicrosoftOfficehasimproved,and

StarOfficenowalsosupportstheOASISOpenDocumentformat.



Note

TheOrganizationfortheAdvancementofStructured

InformationStandards(OASIS)isaninternational

non-profitconsortiumthatdevelopse-business

standards,includingOpenDocument,XMLCatalogs,



andmanyothers.TheOASISWebsiteislocatedat

www.oasis-open.org.



StarOfficehasanopen-sourcesibling,OpenOffice2.0.

OpenOfficeisavailableasafreedownloadandoffersfeatures

similartothoseinrecentversionsofStarOffice,including

OASISOpenDocumentcompatibility.



Note

LearnmoreaboutStarOfficefromtheofficialSun

StarOfficeWebsiteat

www.sun.com/software/star/staroffice/index.jsp.

LearnmoreaboutOpenOfficeanddownloaditfrom

theOpenOfficeWebsiteatwww.openoffice.org.



StarOfficeisavailableforthefollowingplatforms:

Linux(x86)

SolarisIntel

Windows98,2000(SP2orhigher),XP

SolarisonSPARC

OpenOfficesupportsthefollowingplatforms:



Linux(x86)

SolarisIntel

Windows98,Me,2000(SP2orhigher),XP,Windows

Server2003

SolarisonSPARC

MacOSX

TheapplicationsprovidedwithSun'sStarOfficeincludethe

following(*featureisalsoavailableinOpenOffice2.0):

StarOfficeWriter*Aprofessionalwordprocessing

program

StarOfficeCalc*Aspreadsheet

StarOfficeImpress*Agraphicspresentationprogram

StarOfficeDraw*Agraphicsdrawingprogram

StarOfficeBase*Adatabaseforthesuite

StarOfficeScheduleAschedulingapplicationtokeepyour

appointmentsinorder

StarOfficeMailAnemailclient

StarOfficeDiscussionAnewsreaderprogram

Asyoucansee,StarOfficeoffersjustaboutthesame



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