Seagate ST3600057FC 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.7 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.7 FC Product Manual, Rev. A

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Contents Cheetah 15K.7 FC Standard models Self-Encrypting Drive modelsPage Contents About self-encrypting drives Defect and error managementInstallation Interface requirementsSeagate Technology support services Cheetah 15K.7 FC Product Manual, Rev. a Scope Model Number Capacity Self-Encrypting Drive SEDElectromagnetic compatibility Applicable standards and reference documentationStandards Electromagnetic susceptibilityEuropean Union Restriction of Hazardous Substances RoHS Reference documents Ncits TR-20General description Standard features Reliability Media descriptionPerformance Formatted capacitiesUser-installed accessories Factory-installed optionsProgrammable drive capacity Seek performance characteristics Performance characteristicsInternal drive characteristics Access timeStart/stop time General performance characteristicsPrefetch/multi-segmented cache control Cache operation Caching write dataPrefetch operation Recoverable 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 MillisecondsPredictive failures Temperature Log Page 0DhDetermining rate Thermal monitorDST 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 entriesShipping Product warrantyProduct repair and return information AC power requirements Physical/electrical specificationsDC power requirements ST3600057FC DC power requirements Gbit Amps ST3450857FC DC power requirements Gbit AmpsGeneral DC power requirement notes ST3300657FC DC power requirements Gbit AmpsConducted noise immunity Power sequencingCurrent profiles Typical ST3450857FC current profiles Typical ST3300657FC current profiles Power dissipation 600GB model450GB models Environmental limits Temperature a. Operating300GB models Relative humidity Effective altitude sea level a. OperatingShock and vibration Package size Packaged/product weight Drop heightShock Recommended mounting Acoustics Air cleanlinessVibration a. Operating-normal Corrosive environmentRoHS compliance statement Electromagnetic susceptibility See SectionMechanical specifications Mounting configuration dimensionsAbout self-encrypting drives Controlled accessAdmin SP Data encryptionDrive locking Default passwordRandom number generator RNG Data bandsSupported commands Authenticated firmware downloadPower requirements Cryptographic eraseDrive internal defects/errors Defect and error managementDrive error recovery procedures Page FC-AL system errors These values are subject to changeMedia Pre-Scan Background Media ScanDeferred Auto-Reallocation Idle Read After Write Drive ID/option selection InstallationDrive orientation Cooling Air flowDrive mounting GroundingLink services supported Type of frame FC-AL featuresFibre Channel link service frames 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 BytesNPort Login Accept ACC payload Bytes Fibre Channel port login acceptProcess Login Plri payload Process Login Accept ACC payload Bytes Fibre Channel Process Login AcceptFibre Channel fabric login Fabric Login Flogi payload BytesFibre Channel fabric accept login Fabric Login Accept ACC payload BytesFibre Channel Arbitrated Loop options Scsi commands supportedDual port support FC-AL options supportedSupported commands Cheetah 15K.7 FC Product Manual, Rev. a Cheetah 15K.7 FC Product Manual, Rev. a Background Medium Scan 15h Inquiry data Mode Sense dataCheetah 15K.7 FC inquiry data Bytes Data hex Page Mode Data Header Block Descriptor Ec b2 5c 00 00 02 Supported Feature or condition Miscellaneous operating features and conditionsMiscellaneous features 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 10.5.11 SEL6 through SEL0 ID linesArbitrated loop physical address Alpa values SettingHex Dec TTL input characteristics provides the TTL characteristics Signal characteristicsDevice control codes FC Differential output LED driver signalsFC Differential input Receive eye diagram Eye diagram data values Link rate GHz Presales Support Seagate Technology support servicesTechnical Support Data Recovery Services Authorized Service Centers Warranty ServiceData Recovery Services Call Center Toll-free Direct dial Index NumericsDevctrlcode FCP Mtbf Page See also cooling Page Cheetah 15K.7 FC Product Manual, Rev. a Page Seagate Technology LLC
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