Seagate ST3146756FC (FDE) manual Determining rate, Predictive failures, Thermal monitor

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Determining rate

S.M.A.R.T. monitors the rate at which errors occur and signals a predictive failure if the rate of degraded errors increases to an unacceptable level. To determine rate, error events are logged and compared to the number of total operations for a given attribute. The interval defines the number of operations over which to measure the rate. The counter that keeps track of the current number of operations is referred to as the Interval Counter.

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.

5.2.5Thermal monitor

Cheetah 15K.6 FC 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 which is the maximum temperature limit according to the drive specification. The second trip point is user-selectable using the Log Select command. The reference temperature parameter in the temperature 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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Cheetah 15K.6 FC Product Manual, Rev. C

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Contents ST3450856FC ST3300656FCST3146356FC Page Contents Physical/electrical specifications Defect and error managementInstallation Interface requirementsSeagate Technology support services Cheetah 15K.6 FC Product Manual, Rev. C Scope Model Number Full Disk Encryption FDECheetah 15K.6 FC Product Manual, Rev. C Applicable standards and reference documentation StandardsElectromagnetic compatibility Electromagnetic susceptibilityEuropean Union Restriction of Hazardous Substances RoHS Reference documents Ncits TR-20Cheetah 15K.6 FC Product Manual, Rev. C General description Standard features Media description PerformanceReliability Formatted capacitiesFactory-installed options User-installed accessoriesPerformance characteristics Internal drive characteristicsSeek performance characteristics Access timeFormat command execution time minutes General performance characteristicsStart/stop time 176 144 100Prefetch/multi-segmented cache control Cache operationCaching write data Prefetch operation Reliability specifications Error rates Recoverable Errors Unrecoverable ErrorsReliability and service Seek errorsInterface errors Preventive maintenance4 S.M.A.R.T Controlling S.M.A.R.TPerformance impact MillisecondsTemperature Log Page 0Dh Determining ratePredictive failures Thermal monitorState of the drive prior to testing Drive Self Test DSTDST failure definition ImplementationShort and extended tests Short test Function Code 001bExtended test Function Code 010b Log page entriesProduct warranty ShippingProduct repair and return information Cheetah 15K.6 FC Product Manual, Rev. C Physical/electrical specifications AC power requirementsDC power requirements ST3450856FC DC power requirements Gbit Amps ST3450056FC DC power requirements Gbit AmpsST3300656FC DC power requirements Gbit Amps ST3300056FC DC power requirements Gbit AmpsST3146356FC DC power requirements Gbit Amps ST3146756FC DC power requirements Gbit AmpsGeneral DC power requirement notes Power sequencingConducted noise immunity Current profilesTypical ST3450856FC current profiles Typical ST3450056FC current profiles Typical ST3300656FC current profiles Typical ST3300056FC current profiles Typical ST3146356FC current profiles Typical ST3146756FC current profiles Power dissipation 450GB models300GB models Temperature Environmental limits146GB models Relative humidity Effective altitude sea levelPackage size Packaged/product weight Drop height Shock and vibrationShock Recommended mounting Air cleanliness VibrationAcoustics Corrosive environmentRoHS compliance statement Mechanical specifications Mounting configuration dimensionsDefect and error management Drive internal defects/errorsDrive error recovery procedures Page FC-AL system errors Background Media ScanMedia Pre-Scan Deferred Auto-ReallocationIdle Read After Write Installation Drive ID/option selectionDrive orientation CoolingDrive mounting GroundingPage Cheetah 15K.6 FC Product Manual, Rev. C FC-AL features Fibre Channel link service framesLink services supported Type of frame Interface requirementsFibre Channel task management functions Fibre Channel task management responsesFC Scsi FCP response codes Function name Response code Fibre Channel port login NPort login Plogi payload BytesFibre Channel port login accept Fibre Channel Process LoginNPort Login Accept ACC payload Bytes Process Login Plri payloadFibre Channel Process Login Accept Fibre Channel fabric loginProcess Login Accept ACC payload Bytes Fabric Login Flogi payload BytesFibre Channel fabric accept login Fabric Login Accept ACC payload BytesScsi commands supported Dual port supportFibre Channel Arbitrated Loop options FC-AL options supportedSupported commands Cheetah 15K.6 FC Product Manual, Rev. C Cheetah 15K.6 FC Product Manual, Rev. C Supported commands Mode Sense data Inquiry dataCheetah 15K.6 FC inquiry data Bytes Data hex Page Mode Data Header 000000 Cheetah 15K.6 FC Product Manual, Rev. C Miscellaneous operating features and conditions Miscellaneous featuresSupported Feature or condition Miscellaneous statusPhysical characteristics FC-AL physical interfacePhysical description Connector requirements Electrical descriptionPin descriptions FC-SCA pin descriptions Pin Signal name Signal type Pin Signal name Signal typeFC-AL transmitters and receivers Power Fault LED OutEnable port bypass signals Active LED OutMotor start controls Parallel Enclosure Services Interface ESI 11 SEL6 through SEL0 ID linesSetting Arbitrated loop physical address Alpa valuesHex Dec Signal characteristics TTL input characteristicsDevice control codes LED driver signals FC Differential outputFC Differential input Receive eye diagram Eye diagram data values Link rate GHz Cheetah 15K.6 FC Product Manual, Rev. C Seagate Technology support services InternetPresales Support Technical SupportWarranty Service Data Recovery Services Authorized Service CentersData Recovery Services Call CenterToll-freeDirect dialFAX Index NumericsFC-AL Flogi Plogi Page See also cooling
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