Seagate ST936751FC, ST973451FC manual Defect and error management, Drive internal defects/errors

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7.0Defect 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 7.4)

•Media Pre-Scan (see Section 7.5)

•Deferred Auto-Reallocation (see Section 7.6)

•Idle Read After Write (see Section 7.7)

Note.The read error rates and specified storage capacities are not dependent on host (initiator) defect man- agement routines.

7.1Drive 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 SCSI Commands Reference Man- ual. Also, more information on the drive Error Recovery philosophy is presented in the Fibre Channel Interface Manual.

7.2Drive 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 SCSI Commands Reference 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.

Savvio 15K.1 FC Product Manual, Rev. B

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Contents ST973451FC ST936751FC Savvio 15K.1 FCPage Contents Defect and error management Physical/electrical specificationsInstallation Interface requirementsSeagate Technology support services Savvio 15K.1 FC Product Manual, Rev. B List of Figures Page Savvio 15K.1 family disc drive ScopeSavvio 15K.1 FC Product Manual, Rev. B Standards Applicable standards and reference documentationElectromagnetic compatibility Electromagnetic susceptibilityEuropean Union Restriction of Hazardous Substances RoHS Ncits TR-19 Reference documentsSavvio 15K.1 FC Product Manual, Rev. B General description Standard features Performance Media descriptionReliability Formatted capacitiesFactory-installed accessories OptionsProgrammable drive capacity Internal drive characteristics Performance characteristicsSeek performance characteristics Access timeFormat command execution time General performance characteristicsStart/stop time Prefetch/multi-segmented cache control Cache operationCaching write data Prefetch operation Reliability specifications Error ratesRecoverable Errors Unrecoverable Errors Reliability and serviceSeek errors Interface errorsHot plugging the drive 4 S.M.A.R.TControlling S.M.A.R.T Reporting control Performance impactDetermining rate Predictive failuresParameter Code Description Temperature Log Page 0DhDrive Self Test DST DST failure definitionImplementation State of the drive prior to testingInvoking DST Short and extended testsLog page entries Product warrantyAbort ShippingProduct repair and return information Physical/electrical specifications AC power requirementsDC power requirements General DC power requirement notes Conducted noise immunity Power sequencingCurrent profiles +5V +12VTypical ST936751FC drive +12V and +5V current profiles Power dissipation CURRENT/POWER vs Throughput FC 1GB Random 8 Block ReadsST973451FC CURRENT/POWER vs Throughput FC 4GB Random 8 Block Reads ST936751FC FC CURRENT/POWER vs Throughput FC 1GB Random 8 Block ReadsTemperature FC CURRENT/POWER vs Throughput FC 4GB Random 8 Block ReadsEnvironmental limits Effective altitude sea level Relative humidityShock and vibration ShockPackage size Packaged/product weight Drop height Recommended mounting Air cleanliness Vibration Corrosive environment Acoustics Drive dimensions inches Mechanical specificationsDefect and error management Drive internal defects/errorsDrive error recovery procedures FC-AL system errors Background Media Scan Media Pre-ScanDeferred Auto-Reallocation Idle Read After Write Installation Drive orientationCooling Grounding Drive mountingFibre Channel link service frames FC-AL featuresLink services supported Type of frame Interface requirementsFibre Channel task management responses Fibre Channel task management functionsFibre Channel Scsi FCP task management functions Task name SupportedNPort login Plogi payload Bytes Fibre Channel port loginFibre Channel Process Login Fibre Channel port login acceptNPort Login Accept ACC payload Bytes Process Login Plri payloadFibre Channel fabric login Fibre Channel Process Login AcceptProcess Login Accept ACC payload Bytes Fabric Login Flogi payload BytesFabric Login Accept ACC payload Bytes Fibre Channel fabric accept loginFibre Channel Arbitrated Loop options Dual port supportFC-AL options supported Option SupportedSupported commands Command code Command name Scsi commands supportedDisconnect/reconnect control page 02h Savvio 15K.1 FC Product Manual, Rev. B LBdata Supported commands Command code Supported 4 Command name Savvio inquiry data Bytes Data hex Inquiry dataMiscellaneous features Miscellaneous operating features and conditionsSupported Feature or condition Miscellaneous statusPhysical characteristics FC-AL physical interfacePhysical description Connector requirements Part description Positions Part number FeaturesElectrical description FC-SCA pin descriptions Pin Signal name Signal type Pin Signal name Signal typePin descriptions Power Fault LED OutFC-AL transmitters and receivers Enable port bypass signals Active LED OutMotor start controls 11 SEL6 through SEL0 ID lines Parallel Enclosure Services Interface ESISetting Arbitrated loop physical address Alpa valuesHex Dec Signal characteristics TTL input characteristicsDevice control codes Differential Pecl input Differential Pecl outputSavvio 15K.1 FC Product Manual, Rev. B Internet Seagate Technology support servicesPresales Support Technical SupportWarranty Service Data Recovery Services Authorized Service CentersData Recovery Services Call Center Toll-free Direct dial Numerics IndexFAN Page Plogi SEL ID See also cooling
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