Seagate ST91000641SS, ST9500621SS, ST9500620SS, ST9500622SS Predictive failures, Thermal monitor

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S.M.A.R.T. measures error rates. All errors for each monitored attribute are recorded. A counter keeps track of the number of errors for the current interval. This counter is referred to as the Failure Counter.

Error rate is the number of errors per operation. The algorithm that S.M.A.R.T. uses to record rates of error is to set thresholds for the number of errors and their interval. If the number of errors exceeds the threshold before the interval expires, the error rate is considered to be unacceptable. If the number of errors does not exceed the threshold before the interval expires, the error rate is considered to be acceptable. In either case, the inter- val and failure counters are reset and the process starts over.

Predictive failures

S.M.A.R.T. signals predictive failures when the drive is performing unacceptably for a period of time. The firm- ware keeps a running count of the number of times the error rate for each attribute is unacceptable. To accom- plish this, a counter is incremented each time the error rate is unacceptable and decremented (not to exceed zero) whenever the error rate is acceptable. If the counter continually increments such that it reaches the pre- dictive threshold, a predictive failure is signaled. This counter is referred to as the Failure History Counter. There is a separate Failure History Counter for each attribute.

6.2.5Thermal monitor

Constellation.2 drives implement a temperature warning system which:

1.Signals the host if the temperature exceeds a value which would threaten the drive.

2.Signals the host if the temperature exceeds a user-specified value.

3.Saves a S.M.A.R.T. data frame on the drive which exceeds the threatening temperature value.

A temperature sensor monitors the drive temperature and issues a warning over the interface when the tem- perature exceeds a set threshold. The temperature is measured at power-up and then at ten-minute intervals after power-up.

The thermal monitor system generates a warning code of 01-0B01 when the temperature exceeds the speci- fied limit in compliance with the SCSI standard. The drive temperature is reported in the FRU code field of mode sense data. You can use this information to determine if the warning is due to the temperature exceeding the drive threatening temperature or the user-specified temperature.

This feature is controlled by the Enable Warning (EWasc) bit, and the reporting mechanism is controlled by the Method of Reporting Informational Exceptions field (MRIE) on the Informational Exceptions Control (IEC) mode page (1Ch).

The current algorithm implements two temperature trip points. The first trip point is set at 68°C. The second trip point is user-selectable using the Log Select command. The reference temperature parameter in the tempera- ture log page (see Table 1) can be used to set this trip point. The default value for this drive is 68°C, however, you can set it to any value in the range of 0 to 68°C. If you specify a temperature greater than 68°C in this field, the temperature is rounded down to 68°C. A sense code is sent to the host to indicate the rounding of the parameter field.

Table 1: Temperature Log Page (0Dh)

Parameter Code

Description

 

 

0000h

Primary Temperature

 

 

0001h

Reference Temperature

 

 

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Constellation.2 SAS Product Manual, Rev. H

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Contents Standard Models Self-Encrypting Drive Models ST91000640SSST91000641SS ST9500620SSST9500621SSST91000642SS ST9500622SS SED Fips 140-2 ModelsRevision history Contents About Fips About self-encrypting drives Defect and error managementInstallation Interface requirementsPage Constellation.2 SAS Product Manual, Rev. H List of Figures Constellation.2 SAS Product Manual, Rev. H Seagate Technology support services Seagate Online Support and ServicesScope Electromagnetic compatibility Applicable standards and reference documentationStandards Electromagnetic susceptibilityAustralian C-Tick Electromagnetic complianceElectromagnetic compliance for the European Union Korean KCCEuropean Union Restriction of Hazardous Substances RoHS China Restriction of Hazardous Substances RoHS DirectiveReference documents Self-Encrypting Drives Reference ManualGeneral description Standard features Media descriptionFormatted capacities PerformanceReliability Programmable drive capacityFactory-installed options Seek performance characteristics Performance characteristicsInternal drive characteristics Access timeGeneral performance characteristics Start/stop timePrefetch/multi-segmented cache control Cache operationCaching write data Prefetch operationRecoverable Errors Reliability specificationsError rates Unrecoverable ErrorsInterface errors Reliability and serviceSeek errors Preventive maintenancePerformance impact 4 S.M.A.R.TControlling S.M.A.R.T Reporting controlThermal monitor Temperature Log Page 0Dh Parameter Code DescriptionPredictive failures DST failure definition State of the drive prior to testingDrive Self Test DST ImplementationExtended test Function Code 010b Short and extended testsShort test Function Code 001b Log page entriesStorage Product warrantyShipping Product repair and return informationPowerChoice modes Physical/electrical specificationsPowerChoiceTM power management AC power requirements DC power requirements1000GB drive Standard & SED model DC power requirements 500GB drive Standard & SED model DC power requirements Conducted noise immunity General DC power requirement notesPower sequencing Current profiles TB model current profilesGB model current profiles Power dissipation 1TB model drive in 3Gb operation1TB model drive in 6Gb operation 500GB model drive in 3Gb operation 500GB model drive in 6Gb operation Relative humidity Temperature a. OperatingEnvironmental limits Shock Effective altitude sea level a. OperatingShock and vibration Recommended mounting Acoustics Air cleanlinessVibration a. Operating-normal Corrosive environmentSee Section Constellation.2 SAS Product Manual, Rev. H Mechanical specifications Mounting configuration dimensionsValidation Program About FipsPurpose Seagate Enterprise SEDExample of Fips tamper evidence labels About self-encrypting drives Controlled accessAdmin SP Data encryptionDrive locking Authenticated firmware downloadRandom number generator RNG Data bandsPower requirements Supported commandsDrive error recovery procedures Defect and error managementDrive internal defects/errors SAS system errors Deferred Auto-Reallocation Background Media ScanMedia Pre-Scan Protection Information PI Setting and determining the current Type LevelIdle Read After Write Levels of PIIdentifying a Protection Information drive Installation Drive orientationCooling Air flowDrive mounting GroundingSAS features Interface requirementsDual port support Scsi commands supported Supported commandsSupported commands Supported commands Supported commands Constellation.2 inquiry data Mode Sense dataInquiry data Page Block Descriptor 00 00 00 00 3a 38 60 30 00 00 00 00 00 00 02 Miscellaneous status Miscellaneous operating features and conditionsMiscellaneous features SAS physical interface Datum B Section C C Section a a Electrical description Physical characteristicsConnector requirements Pin descriptionsSAS transmitters and receivers Signal characteristicsPower Ready LED OutDifferential signals SAS-2 Specification ComplianceLED drive signal General interface characteristicsIndex NumericsKCC Msid Mtbf See also cooling Page Constellation.2 SAS Product Manual, Rev. H Page Seagate Technology LLC Americas
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