Scope
This document describes the Adaptive Write Back Cache policy of Vess R2600 BBU. It also covers the Advanced Battery Flash backup.The Adaptive Writeback Cache
The Adaptive Writeback Cache feature protects your data by changing the write cache settings while the cache backup battery is offline. When all of the following conditions occur:- The logical drive write policy is set to Write Back.
- The Adaptive Writeback Cache feature is enabled.
- The cache backup battery goes offline.
- Battery not installed.
- Battery remaining capacity is not enough to keep data:
- Advanced Battery Flash Backup disabled:
- less than 72hrs(48hrs for 16GB of memory).
- [Check battery info: EstimateHoldTime field.]
- Advanced Battery Flash Backup enabled:
- less than 3 times backup cycle.
- [Check battery info: EstimateBackupCycle field.]
Example:
[Battery Info]
-------------------------------------------------------------------
EnclosureId: 1
BatteryId: 1 BatteryStatus: FullyCharged
BatteryChemistry: Li-Ion
BatteryCellType: 4-Cell EstimatedHoldTime: 137 hours
TempThresholdDischarge: 60C/140F TempThresholdCharge: 45C/113F
Temperature: 24C/75F CycleCount: 8
Voltage: 8314mV Current: 0mA
RemainingCapacity: 98%
EstimatedBackupCycle: 44
-------------------------------------------------------------------
EnclosureId: 1
BatteryId: 2 BatteryStatus: FullyCharged
BatteryChemistry: Li-Ion
BatteryCellType: 4-Cell EstimatedHoldTime: 138 hours
TempThresholdDischarge: 60C/140F TempThresholdCharge: 45C/113F
Temperature: 25C/77F CycleCount: 8
Voltage: 8303mV Current: 0mA
RemainingCapacity: 98%
EstimatedBackupCycle: 44
The Advanced Battery Flash Backup
To support 16GB Dram(8GB x2).
The controller info: BackupFlashSize need to be over 8GB.
Example:
[Controller Info]
-------------------------------------------------------------------
CtrlId: 1
Alias:
OperationalStatus: OK PowerOnTime: 96 hours 39 minutes
ControllerRole: Primary ReadinessStatus: Active
LUNAffinity: Disabled LunmappingMethod: Name Based
CacheUsagePercentage: 0% DirtyCachePercentage: 0%
PartNo: F29V2FD00000000 SerialNo:
HWRev: A3 WWN:
CmdProtocol: SCSI-3
MemType: DDR3 SDRAM (Slot 1) MemSize: 0 Byte (Slot 1)
: N/A (Slot 2) : N/A (Slot 2)
FlashType: Flash Memory FlashSize: 512 MB
NVRAMType: SRAM NVRAMSize: 256 KB
BootLoaderVersion: 0.00.0000.28 BootLoaderBuildDate: Jul 24, 2012
FirmwareVersion: 1.01.2220.29 FirmwareBuildDate: Apr 25, 2013
SoftwareVersion: 1.01.2220.29 SoftwareBuildDate: Apr 25, 2013
DiskArrayPresent: 1 OverallRAIDStatus: OK
LogDrvPresent: 1 LogDrvOnline: 1
LogDrvOffline: 0 LogDrvCritical: 0
PhyDrvPresent: 5 PhyDrvOnline: 5
PhyDrvOffline: 0 PhyDrvPFA: 0
GlobalSparePresent: 1 DedicatedSparePresent: 0
RevertibleGlobalSparePresent: 1 RevertibleDedicatedSparePresent: 0
RevertibleGlobalSpareUsed: 0 RevertibleDedicatedSpareUsed: 0
WriteThroughMode: No MaxSectorSize: 4 KB
PreferredCacheLineSize: 64 KB CacheLineSize: 64 KB
Coercion: Enabled CoercionMethod: GBTruncate
SMART: Disabled SMARTPollingInterval: 10 minutes
MigrationStorage: DDF CacheFlushInterval: 3 second(s)
PollInterval: 15 second(s) AdaptiveWBCache: Enabled
HostCacheFlushing: Disabled ForcedReadAhead: Disabled
Battery: Enabled
CommonWorld: Disabled
Liquid: Disabled DriveCmd: Enabled
ALUA: Disabled PowerSavingIdleTime: Never
PowerSavingStandbyTime: Never PowerSavingStoppedTime: Never
PseudoDeviceType: CTRL
RestoreACMode: Last state
AdvancedBatteryFlashBackup: Disabled
BackupFlashStatus: Backup flash ready
BackupFlashSize: 7.46 GB
PerfectRebuildAvailable: 16
ApplianceMode: Generic
