RAID Maintenance Free Backup Basic Functionality (RMFBU)

RAIDMaintenanceFreeBackupBasicFunctionality
4
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duringPowerOnSystemTest(POST),andoncethedriveshavebeenscannedandtheraidvolumeis
foundtobehealthy,thedataincacheisflushedtothediskdrives.
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Figure4‐CacheRestore
Withcacheddatawrittentodisk,thecontroller/modulereturnstoanormaloperationalstateandthe
RaidfirmwarecontinuestomonitortheRMFBUhealth,andconductperiodiclearncycles.
StartofDay
ControllerFWBoot
ReplaceRMFUB
RMFBU2Health
Check
Fail
FailUnit
Detected
ChargeRMFBU2
InitiateaLearn
Cycle
Pass
DidNotCompleteForceaLearnCycle
Complete
RMFBU2Charged
andReady
Did
LearnCycle
Successfully
Complete?
ForceControllerto
WriteThrough
Mode
No Yes
PowerLoss
SensedbyController
Periodic
Learn
Dirty
Cache?
No
Data
Writtento
Flash&Held
inFlash
UntilPoweris
Restored
Yes
DirtyCache
BitSet?
PowerRestored No
CacheTransferred
BacktoController
Cache
Yes
NoAction NoAction
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