Seagate ST9146652SS, ST973452SS 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 Models ST9146852SSST9146752SS ST973452SSST973352SSST9146652SS ST973252SS Standard Models Self-Encrypting Drive ModelsPage Contents Interface requirements Defect and error managementInstallation About Fips About self-encrypting drivesPage Savvio 15K.2 SAS Product Manual, Rev. E List of Figures Page Seagate Online Support and Services Seagate Technology support servicesScope Electromagnetic susceptibility Applicable standards and reference documentationStandards Electromagnetic compatibilityKorean MIC Electromagnetic complianceElectromagnetic compliance for the European Union Australian C-TickEuropean Union Restriction of Hazardous Substances RoHS Reference documentsGeneral description Media description Standard featuresFormatted capacities PerformanceReliability Options Programmable drive capacityAccess time Performance characteristicsInternal drive characteristics Seek performance characteristicsStart/stop time Format command execution timeGeneral performance characteristics Cache 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 DC power requirements Physical/electrical specificationsAC power requirements Gbit mode Amps 146GB models DC power requirements73GB models DC power requirements Conducted noise immunity General DC power requirement notesPower sequencing Current profile for 146GB models Current profilesCurrent profile for 73GB models 146GB models in 3.0 Gbit operation Power dissipation146GB models in 6.0 Gbit operation 73GB models in 3.0 Gbit operation 73GB models in 6.0 Gbit operationRelative humidity Temperature a. OperatingEnvironmental limits Shock Effective altitude sea level a. OperatingShock and vibration Recommended mounting Corrosive environment Air cleanlinessVibration a. Operating-normal Acoustics 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 Savvio inquiry data Mode Sense dataInquiry data Page Mode Data Header 00 00 05 12 8B 00 10 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 descriptionSAS transmitters and receivers SAS pin descriptionsSignal characteristics Additional information SAS-2 Specification complianceGeneral interface characteristics Savvio 15K.2 SAS Product Manual, Rev. E Numerics IndexIraw Msid Mtbf See also cooling
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