存储中卷组的基本概念.pptx

存储中卷组的基本概念

Providesforhighlyavailabledatadespiteadiskfailure01Providesforonlinereconstructionoflostdata02Costsspace03Industrystandardredundancyalgorithms04RAIDAsolution

RAIDConcept-ParityStorageCapacity=(DiskCapacity)-(ParityData)01ParityDataisredundantinformationthatcanbeusedfordatareconstruction.02

RAIDConcept–theCostForRAID1,theParityDatauses50%ofthetotaldiskspace;dataiseithermirrored,ortherearetwocopiesofthedata.1ForRAID5,theParityDatauses1/(#ofdisks)oftotaldiskspaceandparitydataisinterleavedamongalldisks2

RAIDConcept:

XPArrayRAIDGroupRAIDdataisprotectedusablestoragespaceusersDONOTknowexactlywerethedataisvendorsimplementRAIDtypesindifferentways.ThinkofRAIDprotectedXPArraystoragespaceinalogicalway:

GeneralConcept:

FromDiskstoRAIDGroupAGroupofDisksARAIDGroupRAIDControlProtectedDataUn-ProtectedDataFromagroupofindependentdiskstoaRAIDgroup

XPSpecificConcept:XPArrayParityGroupFromaXPArrayMarketingArrayGroupofindependentdiskstoanXPArrayParityGroupXPMarketingArrayGroupXPArrayParityGroupRAIDControlProtectedDataUn-ProtectedData

XPArrayFreeSpaceUsablespaceintheXPArrayisfoundwithinaParityGroupandiscalledFreeSpace.FreeSpaceisavailabletothecustomer,butNOTinitsrawform.FreeSpaceisavailalableforuseAFTERtheArraygrouphasbeenformatted.Anarraymayhave200GbytesofrawFreeSpaceperaParityGroupthatmustbeformattedforcustomerusage.

CreatingaParityGroupQ. HowisFreeSpacecreated?

A. BycreatingaParityGroup.Process:ARAIDlevelmustbedefinedforanXPArrayDomain–thisshouldalreadyhavebeenperformed.AMarketingArrayGroupofdisksmustbeinstalledintothearrayDomain.Now,wehaveaParityGroupwithFreeSpaceavailable!

UsingFreeSpace10Sept2004HPRestrictedTouseFreeSpacefordatastorage,fourtasksmustbeperformed.Defin