Seagate ST3300955FC Reporting control, Determining rate, Predictive failures, Thermal monitor

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Reporting control

Reporting is controlled by the MRIE bits in the Informational Exceptions Control mode page (1Ch). Subject to the reporting method, the firmware will issue to the host an 01-5Dxx sense code. The error code is preserved through bus resets and power cycles.

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 NS 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

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Cheetah NS FC Product Manual, Rev. A

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Contents Cheetah NS FC ST3400755FC ST3300955FCPage Cheetah NS FC Product Manual, Rev. a Cheetah NS FC Product Manual, Rev. a Contents Installation Defect and error managementInterface requirements Seagate Technology support services Cheetah NS FC Product Manual, Rev. a List of Figures Page Scope Cheetah NS FC Product Manual, Rev. a Standards, compliance and reference documents StandardsElectromagnetic compatibility Electromagnetic susceptibilityCompliance Reference documents Ncits TR-19Cheetah NS FC Product Manual, Rev. a General description Standard features Media descriptionPerformance ReliabilityFormatted capacities Programmable drive capacityFactory-installed options User-installed accessoriesPerformance characteristics Internal drive characteristicsAccess time Seek performanceGeneral performance characteristics Format command execution time minutesStart/stop time Cache operation Prefetch/multi-segmented cache controlCaching write data Prefetch operation Reliability specifications Error ratesRecoverable Errors Unrecoverable ErrorsReliability and service Seek errorsInterface errors Preventive maintenance4 S.M.A.R.T Controlling S.M.A.R.TPerformance impact MillisecondsReporting control Determining ratePredictive failures Thermal monitorState of the drive prior to testing Parameter Code DescriptionDrive Self Test DST DST failure definitionInvoking DST Short and extended testsShort test Function Code 001b Extended test Function Code 010bProduct warranty AbortShipping Product repair and return informationCheetah NS FC Product Manual, Rev. a Physical/electrical specifications AC power requirementsDC power requirements DC power requirements for ST3400755FC model Gbit AmpsGeneral DC power requirement notes DC power requirements for ST3300955FC model Gbit AmpsPower sequencing Conducted noise immunityCurrent profiles Cheetah NS FC Product Manual, Rev. a Power dissipation ST3400755 CURRENT/POWER vs Throughput FC 4GBST3400755FC Random 8 Block ReadsST3300955 CURRENT/POWER vs Throughput FC 4GB ST3300955FCEnvironmental limits TemperatureRelative humidity Package size Packaged/product weight Drop height Effective altitude sea levelShock and vibration ShockRecommended mounting Air cleanliness VibrationAcoustics Corrosive environmentX表示该部件（于同类物品程度上）所含的危险和有毒物质中国RoHS MCV标准所定义的门槛值。 China Restriction of Hazardous Substances RoHS DirectiveMechanical specifications Mounting configuration dimensionsCheetah NS FC Product Manual, Rev. a Drive internal defects/errors Defect and error managementDrive error recovery procedures 77.87 Background Media Scan FC-AL system errorsMedia Pre-Scan Deferred Auto-Reallocation Idle Read After WriteInstallation Drive ID/option selectionDrive orientation CoolingDrive mounting Air flowGrounding Cheetah NS FC Product Manual, Rev. a FC-AL features Fibre Channel link service framesLink services supported Type of frame Interface requirementsFibre Channel task management responses Fibre Channel task management functionsFC 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 BytesDual port support Fibre Channel Arbitrated Loop optionsFC-AL options supported Option SupportedScsi commands supported Supported commands Command code Command nameVerify error recovery page 07h Cheetah NS FC Product Manual, Rev. a Temperature page 0Dh Inquiry data Mode Sense dataCheetah NS FC inquiry data Bytes Data hex Page Mode Sense 10 Byte Header Data Mode Data Header Miscellaneous operating features and conditions Miscellaneous featuresSupported Feature or condition Miscellaneous statusFC-AL physical interface Physical characteristicsPhysical description Electrical description Connector requirementsPin descriptions Pin Signal name Signal type FC-SCA pin descriptions Pin Signal name Signal typeFC-AL transmitters and receivers Power Fault LED OutActive LED Out Enable port bypass signalsMotor start controls Parallel Enclosure Services Interface ESI 11 SEL6 through SEL0 ID linesArbitrated loop physical address Alpa values SettingHex Dec TTL input characteristics Signal characteristicsDevice control codes FC Differential output LED driver signalsFC Differential input Receive eye diagram Eye diagram data values Link rate GHz Seagate Technology support services InternetPresales Support Technical SupportData Recovery Services Authorized Service Centers Warranty ServiceData Recovery Services Call Center Toll-free Direct dial Index NumericsFAN Flogi Plogi SEL ID See also cooling
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