Spectra T950 - Global Spare Drives; Redundant Power Supplies

Chapter 2 — Architecture Overview High-Availability Configurations
November 2016 User Guide—Spectra T950 Library
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Drive Connectivity Failover
TheFibreChanneldrivesusedwiththelibraryareequippedwithtwo
FibreChannelports.ThetwoFibreChannelportscannotbeused
simultaneouslytoprovideredundantdatapathsbetweenthehostsandthe
drive.However,theycanbeusedtoprovidefailovercapabilityintheevent
thatcommunicationtotheportcurrentlyinuseisinterrupted.This
failovercanbeaccomplishedseveralways,including:
 Manuallydisconnectthefiberopticcablefromthefailedportand
connectittotheotherport.Youmayneedtoreconfigureyourhost
softwaretorecognizethealternateport.
 ConnecteachportonthedrivetoaseparateFibreChannelHBAinthe
host.Youcanalsouseadual‐portFibreChannelHBA.Configureone
HBA(orHBAport)astheprimaryconnectionandtheotherHBA(or
HBAport)asthefailoverconnection.Installfailoversoftwareonthe
hostcomputertocontrolthetransferofI/OfromoneHBAtotheother
incaseofafailure.Youmayalsoneedtoconfigureyourstorage
managementsoftwaretocorrectlyrecognizebothports.Refertoyour
failoversoftware,HBA,andstoragemanagementsoftware
documentationforinstructions.
Note: TapedrivessoldbySpectraLogicdonotsupportMPIO.
Global Spare Drives
TheBlueScaleGlobalSparefeatureprovidesawaytoremotelysubstitute
anavailableTS11x0technologyorFibreChannelLTO‐4orlatergeneration
driveinthelibraryforafaileddriveofthesametype.Thefeatureletsyou
configureaninstalleddriveasadesignatedspareforotherdrivesinthe
library.Thisdrivecanthenbesubstitutedforafaileddriveinanypartition
thatisconfiguredtousetheGlobalSparedrive.Whenadrivefails,you
simplylogintotheBlueScalewebinterfacefromanylocation,selectthe
GlobalSpareoptionforthefaileddrive,andcontinue
normaloperations.
Youcanthenphysicallyreplacethefaileddriveatyourconvenience.See
AssignGlobalSpareDrivesonpage195andUsingaGlobalSpareDriveon
page396formoreinformation.
Redundant Power Supplies
Thelibraryrequiresone5/12VDCpowersupplyperDBAwithan
installeddrive.InstallinganoptionalN+1powersupply,whereNisthe
numberofDBAswithdrivesinstalled,providesredundancyandfailover
protectionintheeventthatasinglepowersupplyfails.Inalibrarywith
threeDBAs,if
fourormorepowersupplymodulesareinstalled,uptotwo
powersuppliescanfail.Thesurvivingpowersuppliesload‐shareinorder
toprovidesufficientpowertotheDBAstoallowbackupstocontinueuntil
thefailedpowersuppliesarereplaced.