SAN存储虚拟化关键技术的研究和设计摘要

iSANSANSANSANSANIP-SAN””SANIP-SAN1.SAN2.ii3.4.IP-SANSNMPSANiiiResearchandDesignofStorageVirtualizationinaSANABSTRACTAsthefourthgenerationofstoragetechnology,StorageAreaNetworkprovideshighconnectivityandscalabilityofnetworkstoragedevice.However,withhundredsofheterogeneousstoragedevicesandhostsconnectedbynetworks,theconsequentcomplexityofstoragemanagementconfusedevensophisticatednetworkadministrator.It'sthecomplexproblemofstoragemanagementinSANthatresultinstoragevirtualization.TodayoneofthemostconfusedtopicsinITindustryisstoragevirtualization.Althoughvirtualhasalreadycomeupwithsuchconceptsasvirtualmemory,virtualdisplay,andvirtualtapeinOSdesignmanyyearsago.Butastowhatisstoragevirtualization,thereisnoclearandstandarddefinitionbyfar.ThereislackofstandardsforSANsinceSANtechnologyisinthestageofearlydevelopment,sodoesthestoragevirtualization.Truestoragevirtualizationdevelopmentisinitsembryostageformoststorageindustrialvendors,althoughmanyofthemacclaimtheiraccomplishmentsinstoragevirtualization.Inthisarticle,thedeficiencyanddefectsofplainSANmanagementhavebeenpointedoutandthereforetogetherwithadvantagesofstoragemanagementofvirtualization.Aftercleardescriptionofmanystoragevirtualizationschemesindifferentaspects,avirtualizationschemeissetuponthebasisofformerIP-SANplaindiskresourcemanagementsystem.InadditiontomanagementofphysicaldisksinSAN,thisschemecouldcreatehierarchicalstoragepoolandenablesapplicationserversinSANtheabilityofusingpoolasaverybiglocaldisk.TotalSANvirtualizationcouldinvolvemanydetailsofbothsoftwareandhardwareinSAN.ThevirtualizationdesignprovidedinthisarticleisanextensionoforiginalIP-SANmanagementsoftware.Thecontentsofthisarticleincludethefollowingtopics:1.AnalyzethedifficultiesofplainSANmanagementanddiscussthedeficiencyofstoragedistributionforapplicationlevel.Comparedwithstoragevirtualization,manyadvantagesintechnologyforstorageapplicationaredescribedindetail.2.Describeindetailtheconceptsofstoragevirtualizationanditsvarioussolutionsfromdifferentaspects,suchaswhatstoragevirtualizationcreates,wherevirtualizationlayerresides,andhowitisimplementedivetc.3.Introducevolumemanagerasthebasisofcreatinghierarchicalstoragepool,describeittheoryandoperationmechanismindetail.Comparetwodifferenttypesofvolumemanager,LVMandEVMS.4.DesignindetaildifferentpartofextensionforIP-SANmanagementsoftware.KeyWords:StorageVirtualization,SAN,VolumeManagementSNMP2004117viii1-2SAN.............................................................................11-3SAN.................................................................31-4..............................................................61-5I/O................................................................61-6I/O...............................................................72-1SAN...................................................172-2............................................................172-3................................................................................182-4................................................................192-5............................................................................202-6.............................................................................222-7............................................................222-8..............................................232-9........................................................................242-10..................................................................252-11..................................................252-12..........................................................262-13SAN.............................................................273-1........................................................................343-2LVM............................................................................353-3EVMS...............................................................................393-4EVMS....................................................................404-1SAN...........................................................444-2.....................................................444-3IP-SAN......................................................................454-4IP-SAN..................................................................464-5LVM........................................................................484-6MIB...........................................................494-7MIB...........................................................494-8volumeGroupMIB...........................................504-9volumeAuthMIB.............................................504-10LVM..........................................................................514-11LVM......................................................524-12..................................................................................534-13......................................................................55ix4-14..........................................................562-1...........................