•RAID5:block-levelstripingwithdistributedparity
RAID5usesdiskstripingandparitydataacrossalldrives(distributedparity)toprovidehighdata
throughput,especiallyforsmallrandomaccess.RAID5distributesparityalongwiththedataandrequires
alldrivesbutonetobepresenttooperate;drivefailurerequiresreplacement,butthearrayisnot
destroyedbyasingledrivefailure.Upondrivefailure,anysubsequentreadoperationscanbecalculated
fromthedistributedparitysothatthedrivefailureismaskedfromtheenduser.Thearraywillhavedata
lossintheeventofaseconddrivefailureandisvulnerableuntilthedatathatwasonthefailingdriveis
rebuiltontoareplacementdrive.Asingledrivefailureinthesetwillresultinreducedperformanceof
theentiresetuntilthefailingdrivehasbeenreplacedandrebuilt.
RAID5requiresaminimumnumberofthreeharddiskdrives.
•RAID10:acombinationofRAID0andRAID1
RAID10consistsofstripeddataacrossmirroredspans.ARAID10drivegroupisaspanneddrive
groupthatcreatesastripedsetfromaseriesofmirroreddrives.RAID10allowsamaximumofeight
spans.YoumustuseanevennumberofdrivesineachRAIDvirtualdriveinthespan.TheRAID1
virtualdrivesmusthavethesamestripesize.RAID10provideshighdatathroughputandcompletedata
redundancybutusesalargernumberofspans.
RAID10requiresaminimumnumberoffourharddiskdrivesandalsorequiresanevennumberofdrives,
forexample,sixharddiskdrivesoreightharddiskdrives.
•RAID50:acombinationofRAID0andRAID5
RAID50usesdistributedparityanddiskstriping.ARAID50drivegroupisaspanneddrivegroupin
whichdataisstripedacrossmultipleRAID5drivegroups.RAID50worksbestwithdatathatrequires
highreliability,highrequestrates,highdatatransfers,andmedium-to-largecapacity.
Note:HavingvirtualdrivesofdifferentRAIDlevels,suchasRAID0andRAID5,inthesamedrivegroupis
notallowed.Forexample,ifanexistingRAID5virtualdriveiscreatedoutofpartialspaceinanarray,the
nextvirtualdriveinthearrayhastobeRAID5only.
RAID50requiresaminimumnumberofsixharddiskdrives.
FordetailedinformationaboutRAID,referto“IntroductiontoRAID”intheMegaRAIDSASSoftwareUser
GuideonthedocumentationDVDthatcomeswithyourserver.
RAIDforyourserver
ThistopicprovidesinformationabouttheRAIDsupportedbyyourserver.
Note:BeforeconguringRAIDforyourserver,ensurethatyouuseharddiskdrivesthatareofthesametype
(SATAorSAS)andhavethesamecapacitywithinasingleRAIDarray.
YourserversupportsthefollowingtwotypesofRAIDcongurations:
•OnboardSATAsoftwareRAIDcongurationusingtheIntelRapidStorageTechnologyenterprise
program
TheonboardSATAsoftwareRAIDcontrollerisintegratedontheIntelC220chiponthesystemboard.
IfyourserverhasSATAharddiskdrivesthatareconnectedtothesystemboard,youcanusetheIntel
RapidStorageTechnologyenterpriseprogramtocongureRAID.Bydefault,yourserversupports
onboardSATAsoftwareRAIDlevels0,1,5,and10.
Fordetailedinformation,see“ConguringthesystemBIOStoenableonboardSATARAIDfunctionality”
onpage57
.
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