Seagate ST3400755SS manual Reliability and service, Seek errors, Interface errors

Page 22

5.1.3Seek errors

A seek error is defined as a failure of the drive to position the heads to the addressed track. After detecting an initial seek error, the drive automatically performs an error recovery process. If the error recovery process fails, a seek positioning error (Error code = 15h or 02h) will be reported with a Hardware error (04h) in the Sense Key. Recoverable seek errors are specified at Less than 10 errors in 108 seeks. Unrecoverable seek errors (Sense Key = 04h) are classified as drive failures.

5.1.4Interface errors

An interface error is defined as a failure of the receiver on a port to recover the data as transmitted by the device port connected to the receiver. The error may be detected as a running disparity error, illegal code, loss of word sync, or CRC error.

5.2Reliability and service

You can enhance the reliability of disk drives by ensuring that the drive receives adequate cooling. Section 6.0 provides temperature measurements and other information that may be used to enhance the service life of the drive. Section 8.2 provides recommended air-flow information.

5.2.1Annualized Failure Rate (AFR) and Mean Time Between Failures (MTBF)

These drives shall achieve an AFR of 0.62% (MTBF of 1,400,000 hours) when operated in an environment that ensures the HDA case temperatures do not exceed the values specified in Section 6.4.1.

Operation at case temperatures outside the specifications in Section 6.4.1 may increase the AFR (decrease the MTBF).

AFR and MTBF statistics are poplulation statistics that are not relevant to individual units. AFR and MTBF specifications are based on the following assumptions for Enterprise Storage System environments:

•8,760 power-on hours per year

•250 average on/off cycles per year

•Operating at nominal voltages

•System provides adequate cooling to ensure the case temperatures specified in Section 6.4.1 are not exceeded.

5.2.2Preventive maintenance

No routine scheduled preventive maintenance is required.

5.2.3Hot plugging the drive

When a disk is powered on by switching the power or hot plugged, the drive runs a self test before attempting to communicate on its’ interfaces. When the self test completes successfully, the drive initiates a Link Reset starting with OOB. An attached device should respond to the link reset. If the link reset attempt fails, or any time the drive looses sync, the drive initiated link reset. The drive will initiate link reset once per second but alternates between port A and B. Therefore each port will attempt a link reset once per 2 seconds assuming both ports are out of sync..

If the self-test fails, the does not respond to link reset on the failing port.

Note. It is the responsibility of the systems integrator to assure that no temperature, energy, voltage haz- ard, or ESD potential hazard is presented during the hot connect/disconnect operation. Discharge the static electricity from the drive carrier prior to inserting it into the system.

Caution. The drive motor must come to a complete stop prior to changing the plane of operation. This time is required to insure data integrity.

16

Cheetah NS SAS Product Manual, Rev. B

Page 21 Page 23
Image 22
Page 21 Page 23
Contents Cheetah NS SAS ST3400755SSPage Contents Seagate Technology support services Defect and error managementInstallation Interface requirementsList of Figures Typical ST3400755SS drive +5V and +12V current profilesCheetah NS SAS Product Manual, Rev. B Scope Cheetah NS SAS Product Manual, Rev. B Electromagnetic compatibility Standards, compliance and reference documentsStandards Electromagnetic susceptibilityCompliance Reference documents Cheetah NS SAS Product Manual, Rev. B General description Performance Standard featuresMedia description ReliabilityProgrammable drive capacity Factory-installed optionsFormatted capacities ST3400755SSCheetah NS SAS Product Manual, Rev. B Access time Performance characteristicsInternal drive characteristics Seek performanceGeneral performance characteristics Format command execution time minutesStart/stop time Cache operation Prefetch/multi-segmented cache controlCaching write data Prefetch operation Recoverable Errors Reliability specificationsError rates Unrecoverable ErrorsInterface errors Reliability and serviceSeek errors Preventive maintenancePerformance impact 4 S.M.A.R.TControlling S.M.A.R.T Reporting controlPredictive failures Temperature Log Page 0DhThermal monitor Implementation State of the drive prior to testingDST failure definition Invoking DSTExtended test Function Code 010b Product warrantyShort test Function Code 001b Log page entriesShipping Product repair and return informationCheetah NS SAS Product Manual, Rev. B DC power requirements Physical/electrical specificationsAC power requirements ST3400755SS DC power requirementsConducted noise immunity General DC power requirement notesPower sequencing Current profilesPower dissipation Typical ST3400755SS drive +5V and +12V current profilesTemperature Environmental limitsShock and vibration Relative humidityEffective altitude sea level ShockPackage size Packaged/product weight Drop height Recommended mountingAcoustics Air cleanlinessVibration Corrosive environmentX表示该部件（于同类物品程度上）所含的危险和有毒物质中国RoHS MCV标准所定义的门槛值。 China Restriction of Hazardous Substances RoHS DirectiveMechanical specifications Physical dimensionsCheetah NS SAS Product Manual, Rev. B Drive internal defects/errors Defect and error managementDrive error recovery procedures 77.87 Background Media Scan SAS system errorsMedia Pre-Scan Deferred Auto-Reallocation Idle Read After WriteInstallation Drive orientationCooling Air flowDrive mounting GroundingCheetah NS SAS Product Manual, Rev. B SAS features Interface requirementsDual port support Commands supported by Cheetah NS SAS family drives Scsi commands supportedCommand name Command code Supported Commands supported by Cheetah NS SAS family drives Commands supported by Cheetah NS SAS family drives Commands supported by Cheetah NS SAS family drives Inquiry data Mode Sense dataCheetah NS SAS inquiry data Bytes Data hex Page 2.1 ST3400755SS Mode Sense data Mode PagesSupported Feature or condition Miscellaneous operating features and conditionsMiscellaneous features Miscellaneous statusSAS physical interface Datum B Physical characteristics Connector requirementsPin descriptions Pin Signal name Signal typeElectrical description SAS pin descriptionsSAS transmitters and receivers Signal characteristicsPower Ready LED OutGeneral interface characteristics LED drive signalDifferential signals Eye masks Eye masks overviewAbsolute amplitude Receive eye maskJitter tolerance masks Normalized time in UIJitter Peak-toSinusoidal Frequency in kHzTransmitter signal characteristics Signal characteristica Units GbpsMaximum allowable jitter Receiver signal characteristicsSignal characteristic Units Gbps Gbps m, n Deterministic jitterqCompliant jitter test pattern Cjtpat Impedance specificationsReceiver jitter tolerance Impedance requirements Sheet 1Impedance requirements Sheet 2 Transmitter characteristicsElectrical TxRx connections = -5,437dB Shows the zero-length test load Receiver characteristics Cheetah NS SAS Product Manual, Rev. B Presales Support Seagate Technology support servicesInternet Technical SupportData Recovery Services Authorized Service Centers Warranty ServiceData Recovery Services Call Center Toll-free Direct dial Index NumericsPage SAS See also cooling
Top Page Image Contents