Seagate ST35000414SS, ST35000415SS Defect and error management, Drive internal defects/errors

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8.0Defect 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 8.4)

•Media Pre-Scan (see Section 8.5)

•Deferred Auto-Reallocation (see Section 8.6)

•Idle Read After Write (see Section 8.7)

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

8.1Drive 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.

8.2Drive 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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ConstellationES Series SAS Product Manual, Rev. D

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Contents ST32000444SS ST31000424SS ST3500414SS ST32000445SS ST31000425SS ST3500415SSStandard Models Self-Encrypting Drive ModelsRevision history Contents Defect and error management InstallationAbout self-encrypting drives Interface requirementsSeagate Technology support services ConstellationES Series SAS Product Manual, Rev. D List of Figures ST32000444SS & ST32000445SS model current profilesConstellationES Series SAS Product Manual, Rev. D Scope Applicable standards and reference documentation StandardsElectromagnetic compatibility Electromagnetic susceptibilityElectromagnetic compliance Electromagnetic compliance for the European UnionAustralian C-Tick Korean KCCReference documents European Union Restriction of Hazardous Substances RoHSGeneral description Standard features Media descriptionPerformance ReliabilityFormatted capacities Programmable drive capacityFactory-installed options Performance characteristics Internal drive characteristicsSeek performance characteristics Access timeGeneral performance characteristics Start/stop timePrefetch/multi-segmented cache control Cache operationCaching write data Prefetch operationReliability 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 Reporting controlPredictive failures Temperature Log Page 0Dh Parameter Code DescriptionThermal monitor State 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 entriesShipping Product warrantyProduct repair and return information PowerChoiceTM power management Physical/electrical specificationsPowerChoice modes AC power requirements DC power requirementsConstellationES Series SAS Product Manual, Rev. D ConstellationES Series SAS Product Manual, Rev. D Page Power sequencing General DC power requirement notesConducted noise immunity Current profiles ST32000444SS & ST32000445SS model current profilesST31000424SS & ST31000425SS model current profiles ST3500414SS & ST3500415SS model current profiles Power dissipation ST32000444SS and ST32000445SS in 3Gb operationST32000444SS and ST32000445SS in 6Gb operation ST31000424SS and ST31000425SS in 3Gb operation ST31000424SS and ST31000425SS in 6Gb operation ST3500414SS and ST3500415SS in 3Gb operation ST3500414SS CURRENT/POWER vs Throughput SAS 3.0GBOs per Second ST3500414SS and ST3500415SS in 6Gb operation Environmental limits Temperature a. OperatingRelative humidity Shock and vibration Effective altitude sea level a. OperatingShock Recommended mounting Air cleanliness Vibration a. Operating-normalAcoustics Corrosive environmentElectromagnetic susceptibility Mechanical specifications Mounting configuration dimensionsControlled access Admin SPAbout self-encrypting drives Data encryptionDefault password Random number generator RNGDrive locking Data bandsAuthenticated firmware download Power requirementsSupported commands Cryptographic eraseDrive internal defects/errors Defect and error managementDrive error recovery procedures SAS system errors Media Pre-Scan Background Media ScanDeferred Auto-Reallocation Idle Read After Write Installation Drive orientationCooling Air flowDrive mounting GroundingSAS features Interface requirementsDual port support Scsi commands supported Supported commandsSupported commands Supported commands Supported commands Inquiry data Mode Sense dataConstellation ES inquiry data Page Mode Data Header 74 70 6d b0 00 00 02 3a 38 60 30 00 00 02 Miscellaneous features Miscellaneous operating features and conditionsMiscellaneous status SAS physical interface Datum B Section C C Section a a Physical characteristics Connector requirementsElectrical description Pin descriptionsSignal characteristics PowerSAS transmitters and receivers Ready LED OutSAS-2 Specification Compliance LED drive signalDifferential signals General interface characteristicsSeagate Technology support services Warranty Support Direct.seagate.com Spp.seagate.comWeb Presales SupportTechnical Support Warranty Service Data Recovery Services Authorized Service CentersData Recovery Services Call Center Toll-free Direct dial Presales SupportIndex NumericsKCC Msid Mtbf See also cooling Page ConstellationES Series SAS Product Manual, Rev. D Page Seagate Technology LLC
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