Spectra T950 - Robotic Controller Connectivity

Chapter 2 — Architecture Overview Fibre Channel Connectivity
November 2016 User Guide—Spectra T950 Library
67
Robotic Controller Connectivity
ThelibraryrequireseitheranLTO‐5orlatergenerationFibreChannel
drive,aRIM,oranF‐QIPtoprovidetheroboticcontrolpath.When
configuringastoragepartition,thedeviceyouselecttoprovidetherobotic
controlpathisreferredtoasthe“exportingcontroller”forthepartition.
The
exportingcontrollermakesthepartitionaccessibletothehostsasa
mediachanger(alibrary).Itreceivesthemediachangercommandssent
fromthehosttothelibraryandrelaysthemtotheRCM,whichinturn
processesthemintothemotioncommandsusedtocontroltherobotics.
Youcanselectmultipleexportingcontrollers(drivesorRIMSandF‐QIPs)
forapartitionanduseyourhostsoftwaretoexportthesamechanger
interfaceoverthecontrollerstoprovideredundancy.
 WhenaRIMoranF‐QIPisnotpresent,adirect‐attachedFibreChannel
driveprovidestheroboticcontrolpath,asdescribedinControlPath
ThroughaDirect‐AttachedDrive,below.
 WhenaRIMoranF‐QIPispresent,itcanbeusedtoprovidetherobotic
controlpath,asdescribedinControlPathThroughaRIMorF‐QIPon
page68.
Control Path Through a Direct-Attached Drive
Inadirect‐attacheddriveconfiguration,oneormoredrivesinastorage
partitionaredesignatedas theexportingdrive(alsoknowastheexporting
controller).Thecommandsfromthehosttocontrolthemotionofthe
roboticswithinthepartitionareroutedtotheexportingdrive’slogicalunit
number1(LUN1).Commandstocontroltheoperationoftheexporting
drivearesentfromthehosttoLUN0ofthedrive.
Notes:  Usingadrivetoprovidetheroboticcontrolpathfora
partitionissupportedinBlueScale12.6.3andlater.
 Ifyouhavemultiplestoragepartitions,youmustdesignate
anexportingdriveforeachpartition.
 Adrivecanonlyprovidetheroboticcontrolpathforthe
partitiontowhichitisassigned.
 Youcanselectmultipledrivesascontrollers,andexportthe
samechangerinterfaceoverthedrivestoprovide
redundancy,aslongasyourstoragemanagementsoftware
cansupportthis.Thesemultiplepathscannotbeusedatthe
sametime.
 Assigningmultipledriv eexporterstoonepartitionreducesthe
totalnu mberofpartitionsthatcanbeconfiguredinthelibrary.