Seagate ST450MM0026, ST9600204FC manual Defect and error management, Drive internal defects/errors

Page 41

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 FC system error con- siderations (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)

The read error rates and specified storage capacities are not dependent on host (initiator) defect management 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 Fibre Channel Interface Manual. 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 Fibre Channel 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.

Savvio 10K.4 FC Product Manual, Rev. A

35

Page 40 Page 42
Image 41
Page 40 Page 42
Contents ST9600204FC ST9450404FC Savvio 10K.4 FCRev. a 03/26/10 Initial release Revision historyContents Installation Seagate Technology support services Savvio 10K.4 FC Product Manual, Rev. a Scope Standards Standards, compliance and reference documentsElectromagnetic compatibility Electromagnetic susceptibilityEuropean Union Restriction of Hazardous Substances RoHS Ncits TR-19 Reference documentsGeneral description Media description Standard featuresFormatted capacities PerformanceReliability Programmable drive capacity Factory-installed optionsUser-installed accessories Internal drive characteristics Performance characteristicsAccess time Seek performanceGeneral performance characteristics Format command execution time minutesStart/stop time Prefetch/multi-segmented cache controlCache operation Prefetch operation Caching write dataError rates Reliability specificationsRecoverable Errors Unrecoverable ErrorsSeek errors Reliability and serviceInterface errors Preventive maintenancePerformance impact 4 S.M.A.R.TControlling S.M.A.R.T Determining rate Reporting controlPredictive failures Thermal monitorTemperature Log Page 0Dh State of the drive prior to testingDrive Self Test DST DST failure definitionShort and extended tests Invoking DSTShort test Function Code 001b Extended test Function Code 010bAbort Product warrantyPowerChoice modes Physical/electrical specificationsPowerChoiceTM power management AC power requirements DC power requirements for ST9600204FC model 2Gb 4Gb Amps DC power requirementsDC power requirements for ST9450404FC model 2Gb 4Gb Amps Conducted noise immunity General DC power requirement notesPower sequencing Current profiles Savvio 10K.4 FC Product Manual, Rev. a ST9600204FC Power dissipationST9450404FC Relative humidity Temperature a. OperatingEnvironmental limits Shock Effective altitude sea level a. OperatingShock and vibration Recommended mounting Package size Packaged/product weight Drop heightVibration a. Operating-normal Air cleanlinessAcoustics Corrosive environmentChina Restriction of Hazardous Substances RoHS Directive Mounting configuration dimensions Mechanical specificationsDrive error recovery procedures Defect and error managementDrive internal defects/errors 77.87 Media Pre-Scan FC-AL system errorsBackground Media Scan Idle Read After Write Deferred Auto-ReallocationDrive ID/option selection InstallationDrive orientation CoolingAir flow Drive mountingGrounding Fibre Channel link service frames FC-AL featuresLink services supported Type of frame Interface requirementsFC Scsi FCP response codes Function name Response code Fibre Channel task management functionsFibre Channel task management responses NPort 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 supportedVerify error recovery page 07h Savvio 10K.4 FC Product Manual, Rev. a Temperature page 0Dh Savvio 10K.4 FC inquiry data Bytes Data hex Mode Sense dataInquiry data Page Mode Data Header 34 65 f8 70 00 00 02 Supported Feature or condition Miscellaneous operating features and conditionsPhysical description Physical characteristicsFC-AL physical interface Pin descriptions Connector requirementsElectrical description FC-AL transmitters and receivers FC-SCA pin descriptions Pin Signal name Signal typeFault LED Out PowerMotor start controls Enable port bypass signalsActive LED Out 11 SEL6 through SEL0 ID lines Parallel Enclosure Services Interface ESIAlpa SEL ID Device control codes Signal characteristicsTTL input characteristics FC Differential input LED driver signalsFC Differential output Receive eye diagram Eye diagram data values Link rate GHz Web Seagate Technology support servicesWarranty Support Direct.seagate.com Spp.seagate.com Data Recovery Services Authorized Service Centers Technical Support Warranty ServiceData Recovery Services Call Center Toll-free Direct dial Presales SupportSavvio 10K.4 FC Product Manual, Rev. a Index FCP Flogi Plogi Page See also cooling Page Seagate Technology LLC
Top Page Image Contents