Seagate ST9500431SS, ST9500430SS manual Defect and error management, Drive internal defects/errors

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10.0Defect and error management

Seagate continues to use innovative technologies to manage defects and errors. These technologies are designed to increase data integrity, perform drive self-maintenance, and validate proper drive operation.

SCSI defect and error management involves drive internal defect/error management and SAS system error considerations (errors in communications between the initiator and the drive). In addition, Seagate provides the following technologies used to increase data integrity and drive reliability:

•Background Media Scan (see Section 10.4)

•Media Pre-Scan (see Section 10.5)

•Deferred Auto-Reallocation (see Section 10.6)

•Idle Read After Write (see Section 10.7)

The read error rates and specified storage capacities are not dependent on host (initiator) defect management routines.

10.1Drive internal defects/errors

During the initial drive format operation at the factory, media defects are identified, tagged as being unusable, and their locations recorded on the drive primary defects list (referred to as the “P’ list and also as the ETF defect list). At factory format time, these known defects are also reallocated, that is, reassigned to a new place on the medium and the location listed in the defects reallocation table. The “P” list is not altered after factory formatting. Locations of defects found and reallocated during error recovery procedures after drive shipment are listed in the “G” list (defects growth list). The “P” and “G” lists may be referenced by the initiator using the Read Defect Data command.

Details of the SCSI commands supported by the drive are described in the SAS Interface Manual. Also, more information on the drive Error Recovery philosophy is presented in the SAS Interface Manual.

10.2Drive error recovery procedures

When an error occurs during drive operation, the drive, if programmed to do so, performs error recovery proce- dures to attempt to recover the data. The error recovery procedures used depend on the options previously set in the Error Recovery Parameters mode page. Error recovery and defect management may involve using sev- eral SCSI commands described in the SAS Interface Manual. The drive implements selectable error recovery time limits required in video applications.

The error recovery scheme supported by the drive provides a way to control the total error recovery time for the entire command in addition to controlling the recovery level for a single LBA. The total amount of time spent in error recovery for a command can be limited using the Recovery Time Limit bytes in the Error Recovery mode page. The total amount of time spent in error recovery for a single LBA can be limited using the Read Retry Count or Write Retry Count bytes in the Error Recovery mode page.

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Contents SED Fips 140-2 Model ST9500430SSST9500431SSST9500432SS Standard Model Self-Encrypting Drive ModelRevision history Contents Interface requirements Defect and error managementInstallation About Fips About self-encrypting drivesPower Constellation SAS Product Manual, Rev. E GB model current profiles List of FiguresConstellation SAS Product Manual, Rev. E Seagate Online Support and Services Seagate Technology support servicesScope Electromagnetic susceptibility Applicable standards and reference documentationStandards Electromagnetic compatibilityKorean KCC Electromagnetic complianceElectromagnetic compliance for the European Union Australian C-TickEuropean Union Restriction of Hazardous Substances RoHS Reference documentsGeneral description Media description Standard featuresProgrammable drive capacity PerformanceReliability Formatted capacitiesFactory-installed options Access time Performance characteristicsInternal drive characteristics Seek performance characteristicsStart/stop time General performance characteristicsCache operation Prefetch/multi-segmented cache controlPrefetch operation Caching write dataUnrecoverable Errors Reliability specificationsError rates Recoverable ErrorsPreventive maintenance Reliability and serviceSeek errors Interface errorsReporting control 4 S.M.A.R.TControlling S.M.A.R.T Performance impactThermal monitor Temperature Log Page 0Dh Parameter Code DescriptionPredictive failures Implementation State of the drive prior to testingDrive Self Test DST DST failure definitionLog page entries Short and extended testsShort test Function Code 001b Extended test Function Code 010bProduct repair and return information Product warrantyShipping PowerChoice modes Physical/electrical specificationsPowerChoiceTM power management DC power requirements AC power requirementsPage Conducted noise immunity General DC power requirement notesPower sequencing GB model current profiles Current profilesST9500430SS, ST9500431SS and ST9500432SS in 3 Gbit operation Power dissipationST9500430SS, ST9500431SS and ST9500432SS in 6 Gbit operation Environmental limits Temperature a. OperatingShock Relative humidityEffective altitude sea level a. Operating Shock and vibrationPage Recommended mounting Corrosive environment Air cleanlinessVibration a. Operating-normal Acoustics Mounting configuration dimensions Mechanical specificationsLevel 2 security About FipsPurpose Data encryption Controlled accessAdmin SP About self-encrypting drivesData bands Default passwordRandom number generator RNG Drive lockingCryptographic erase Authenticated firmware downloadPower requirements Supported commandsDrive error recovery procedures Defect and error managementDrive internal defects/errors SAS system errors Deferred Auto-Reallocation Background Media ScanMedia Pre-Scan Idle Read After Write Drive orientation InstallationAir flow CoolingGrounding Drive mountingInterface requirements SAS featuresDual port support Supported commands Scsi commands supportedSupported commands Supported commands Supported commands Constellation inquiry data Mode Sense dataInquiry data Page Mode Data Header Miscellaneous status Miscellaneous operating features and conditionsMiscellaneous features SAS physical interface Datum B Section C C Section a a Pin descriptions Physical characteristicsConnector requirements Electrical descriptionReady LED Out Signal characteristicsPower SAS transmitters and receiversGeneral interface characteristics SAS-2 Specification ComplianceLED drive signal Differential signalsConstellation SAS Product Manual, Rev. E Numerics IndexKCC Msid Mtbf See also cooling Page Constellation SAS Product Manual, Rev. E Page Seagate Technology LLC
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