All data in the subsystem’s controller cache is protected assuming you have both Batteries present and fully charged with at least 72 hours of hold time. Please reference the User Manual on “adaptive write cache” function.
In the event the battery becomes marginal and adaptive write cache feature is enabled (enabled by default) the controller firmware will switch the controller write cache to write thru to protect controller cache data. Physical disk cache is not protected. If this is a concern it is possible to turn off physical disk write caching from WebPAM interface or the CLI. This is a global setting for all drives and it can be found in the WebPAM interface under Device--> PhysicalDrive--> Global Physical Drive Settings See screenshot below). Turning off drive write caching will significantly reduce write performance. Read performance will not be affected
From CLI you can SSH into the Vess Rxxx or VTrak Dxxx:
ssh administrator@<IPAddress>
passoword: password
For the drive global settings help type:
administrator@cli> phydrv -h (this will give you the CLI command line syntax)
How do you check to see if the Adaptive Write Cache feature is disabled? You can check from CLI also the dashboard on the web interface will indicate the problem.
WriteThroughMode: 1 means the Volume write-back is disabled. (See below)
WriteThroughMode: 0 means the Volume write-back is enabled.
administrator@cli> ctrl -v
CtrlId: 1 Alias: OperationalStatus: OK, BGA Running PowerOnTime: 69 hours 14 minutes ControllerRole: Secondary ReadinessStatus: Active LUNAffinity: Enabled LunmappingMethod: Name Based CacheUsagePercentage: 0 DirtyCachePercentage: 0 PartNo: F29VR3620000009 SerialNo: MD4L19915700025 HWRev: A2 WWN: 2100-0001-5562-fc11 CmdProtocol: SCSI-3 ALUA: Enabled MemType1: DDR4 SDRAM (Slot 1) MemSize1: 16 GB (Slot 1) MemType2: DDR4 SDRAM (Slot 2) MemSize2: 16 GB (Slot 2) FlashType: Flash Memory FlashSize: 16 GB NVRAMType: SRAM NVRAMSize: 1 MB BootLoaderVersion: 15.27.0000.38 BootLoaderBuildDate: N/A FirmwareVersion: 13.03.0000.07 FirmwareBuildDate: Aug 14, 2019 SoftwareVersion: 13.03.0000.07 SoftwareBuildDate: Aug 14, 2019 OverallRAIDStatus: OK PhyDrvPresent: 8 PhyDrvOnline: 7 PhyDrvOffline: 0 PhyDrvPFA: 0 GlobalSparePresent: 1 DedicatedSparePresent: 0 RevertibleGlobalSparePresent: 1 RevertibleDedicatedSparePresent: 0 RevertibleGlobalSpareUsed: 0 RevertibleDedicatedSpareUsed: 0 WriteThroughMode: 1 MaxSectorSize: 4 KB PreferredCacheLineSize: 64 CacheLineSize: 64 Coercion: Enabled CoercionMethod: GBTruncate SMARTLog: Disabled SMARTPollingInterval: 10 minutes MigrationStorage: DDF CacheFlushInterval: 3 PollInterval: 15 AdaptiveWBCache: Enabled HostCacheFlushing: Disabled ForcedReadAhead: Disabled CommonWorld: Disabled Liquid: Disabled DriveCmd: Enabled PowerSavingIdleTime: Never PowerSavingStandbyTime: Never PowerSavingStoppedTime: Never PseudoDeviceType: CTRL PerfectRebuildAvailable: 64 VAAIsupport: Enabled SSDTrimSupport: Disabled M.2DevicePresent1: No M.2DeviceSize1: 0 GB(s)
administrator@cli> battery
Id: 1 EnclosureId: 1 Status: Charging Chemistry: Li-Ion CellType: 2-Cell EstimatedBackupCycle: 3 TempThresholdDischarge: 70C/158F TempThresholdCharge: 50C/122F Temperature: 25C/77F CycleCount: 1 Voltage: 8177mV Current: 0mA RemainingCapacity: 94% TotalPowerOnHours: 6 Days 17 Hours ------------------------------------------------------------------------------- Id: 2 EnclosureId: 1 Status: Not present Chemistry: CellType: EstimatedBackupCycle: TempThresholdDischarge: TempThresholdCharge: Temperature: CycleCount: Voltage: Current: RemainingCapacity: TotalPowerOnHours:
