Seagate ST3300557SS, ST3300657SS 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.

The drive firmware error recovery algorithms consists of 13 levels for read recoveries and five levels for write. Each level may consist of multiple steps, where a step is defined as a recovery function involving a single re- read or re-write attempt. The maximum level used by the drive in LBA recovery is determined by the read and write retry counts.

Cheetah 15K.7 SAS Product Manual, Rev. A

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Contents Standard models Self-Encrypting Drive models Cheetah 15K.7 SASPage Contents Interface requirements Defect and error managementInstallation About self-encrypting drivesSeagate Technology support services Cheetah 15K.7 SAS Product Manual, Rev. a Model Number Capacity Self-Encrypting Drive SED ScopeElectromagnetic susceptibility Standards, compliance and reference documentsStandards Electromagnetic compatibilityEuropean Union Restriction of Hazardous Substances RoHS ComplianceReference documents General description Media description Standard featuresPerformance Programmable drive capacity Factory-installed optionsReliability Formatted capacitiesSeek time Performance characteristicsInternal drive characteristics Access timeGeneral performance characteristics Format command execution time minutesStart/stop time Cache operation Prefetch/multi-segmented cache controlPrefetch operation Caching write dataUnrecoverable Errors Reliability specificationsError rates Recoverable ErrorsPreventive maintenance Reliability and serviceSeek errors Interface errorsMilliseconds 4 S.M.A.R.TControlling S.M.A.R.T Performance impactThermal monitor Reporting controlDetermining rate Predictive failuresDST failure definition Temperature Log Page 0Dh Parameter Code DescriptionState of the drive prior to testing Drive Self Test DSTExtended test Function Code 010b Invoking DSTShort and extended tests Short test Function Code 001bProduct repair and return information Product warrantyAbort ShippingAC power requirements Physical/electrical specificationsDC power requirements ST3600057SS ST3600957SS Gbit mode Amps 600 GB DC power requirementsST3450857SS ST3450757SS Gbit mode Amps 450 GB DC power requirementsST3300657SS ST3300557SS Gbit mode Amps 300 GB DC power requirementsConducted noise immunity Power sequencingCurrent profiles Typical 600GB current profiles Typical 300GB current profiles ST3600057SS model Power dissipationST3450857SS model Environmental limits TemperatureST3300657SS model Shock Relative humidityEffective altitude sea level Shock and vibrationPackage size Packaged/product weight Drop height Recommended mounting VibrationRoHS compliance statement Air cleanlinessAcoustics Corrosive environmentPhysical dimensions Mechanical specificationsData encryption Controlled accessAdmin SP About self-encrypting drivesData bands Authenticated firmware downloadRandom number generator RNG Drive lockingSupported commands Power requirementsDrive internal defects/errors Defect and error managementDrive error recovery procedures Page Background Media Scan SAS system errorsDeferred Auto-Reallocation Media Pre-ScanIdle Read After Write Drive orientation InstallationCooling Grounding Drive mountingInterface requirements SAS featuresDual port support Scsi commands supportedCommands supported by Cheetah 15K.6 SAS family drives Command name Command code SupportedCommands supported by Cheetah 15K.6 SAS family drives Commands supported by Cheetah 15K.6 SAS family drives Commands supported by Cheetah 15K.6 SAS family drives Cheetah 15K.7 inquiry data Bytes Data hex Inquiry dataMode Sense data Mode Pages 10.3.2.1 ST3600057SS and ST3600957SS Mode Sense dataDEF CHG Mode Data Header Block Descriptor Mode Pages 10.3.2.2 ST3450857SS and ST3450757SS Mode Sense dataDEF CHG Read Capacity Data Buffer C D E F Mode Pages 10.3.2.3 ST3300657SS and ST3300557SS Mode Sense dataMiscellaneous status Miscellaneous operating features and conditionsMiscellaneous features Supported Feature or conditionPhysical interface SAS physical interfaceDatum B Connector requirements Physical characteristicsSAS pin descriptions Pin Signal name Signal typeElectrical description Pin descriptionsReady LED Out Signal characteristicsPower SAS transmitters and receiversGeneral interface characteristics SAS-2 Specification complianceLED drive signal Differential signalsPresales Support Seagate Technology support servicesTechnical Support Data Recovery Services Authorized Service Centers Warranty ServiceData Recovery Services Call CenterToll-freeDirect dialFAX Cheetah 15K.7 SAS Product Manual, Rev. a Numerics IndexPage SAS Smart
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