Seagate ST9600104SS, ST9600204SS manual 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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Contents Standard Models Self-Encrypting Drive Models ST9600204SSST9600104SS ST9450404SSST9450304SSRev. a 12/15/09 Initial release Revision historyContents Installation Defect and error managementAbout self-encrypting drives Interface requirementsSeagate Technology support services Savvio 10K.4 SAS Product Manual, Rev. a List of Figures Page Scope Standards Applicable standards and reference documentationElectromagnetic compatibility Electromagnetic susceptibilityElectromagnetic compliance for the European Union Electromagnetic complianceAustralian C-Tick Korean KCCEuropean Union Restriction of Hazardous Substances RoHS Reference documentsGeneral description Media description Standard featuresReliability PerformanceFormatted capacities Programmable drive capacityFactory-installed options Internal drive characteristics Performance characteristicsSeek performance characteristics Access timeStart/stop time General performance characteristicsCache operation Prefetch/multi-segmented cache controlCaching write data Prefetch operation Error rates Reliability specificationsRecoverable Errors Unrecoverable ErrorsSeek errors Reliability and serviceInterface errors Preventive maintenance4 S.M.A.R.T Maximum processing delay Fully-enabled delayControlling S.M.A.R.T Performance impactPredictive failures Temperature Log Page 0Dh Parameter Code DescriptionThermal monitor Drive Self Test DST State of the drive prior to testingDST failure definition ImplementationShort test Function Code 001b Short and extended testsExtended test Function Code 010b Log page entriesShipping Product warrantyProduct repair and return information PowerChoiceTM power management Physical/electrical specificationsPowerChoice modes DC power requirements AC power requirementsSavvio 10K.4 SAS Product Manual, Rev. a Page Page Power sequencing General DC power requirement notesConducted noise immunity Current profiles for 600GB models Current profilesCurrent profiles for 450GB models GB models in 3Gb operation Power dissipation600GB models in 6Gb operation 450GB models in 3Gb operation Environmental limits Temperature a. Operating450GB models in 6Gb operation Effective altitude sea level a. Operating Relative humidityShock and vibration Shock Recommended mounting Vibration a. Operating-normal Air cleanlinessCorrosive environment Acoustics Mounting configuration dimensions Mechanical specificationsAdmin SP Controlled accessAbout self-encrypting drives Data encryptionRandom number generator RNG Default passwordDrive locking Data bandsPower requirements Authenticated firmware downloadSupported 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 Drive orientation InstallationAir flow CoolingGrounding Drive mountingInterface requirements SAS featuresDual port support Supported commands Scsi commands supportedSupported commands Supported commands Supported commands Inquiry data Mode Sense dataSavvio inquiry data Page Mode Pages Mode Sense data for ST9600204SS and ST9600104SS drivesMode Sense values for ST9450404SS and ST9450304SS drives Miscellaneous features Miscellaneous operating features and conditionsMiscellaneous status SAS physical interface Datum B Section C C Section a a Connector requirements Physical characteristicsElectrical description Pin descriptionsPower Signal characteristicsSAS transmitters and receivers Ready LED OutLED drive signal SAS-2 Specification complianceDifferential signals General interface characteristicsInternet Seagate Technology support servicesPresales Support Technical SupportData Recovery Services Authorized Service Centers Warranty ServiceData Recovery Services Call Center Toll-free Direct dialFAX Numerics IndexKCC Msid Mtbf See also cooling Page Savvio 10K.4 SAS Product Manual, Rev. a Page Seagate Technology LLC
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