Seagate ST3146855LC, ST3146855LW Reliability and service, Seek errors, Preventive maintenance

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6.1.3Seek 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.

6.2Reliability and service

You can enhance the reliability of Cheetah 15K.5 SCSI disc drives by ensuring that the drive receives ade- quate cooling. Section 7.0 provides temperature measurements and other information that may be used to enhance the service life of the drive. Section 9.3 provides recommended air-flow information.

6.2.1Annualized 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 7.4.1.

Operation at case temperatures outside the specifications in Section 7.4.1 may increase the AFR (decrease the MTBF). AFR and MTBF statistics are population statistics that are not relevant to individual units.

AFR and MTBF specifications are based on the following assumptions for Enterprise Storage System environ- ments:

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 7.4.1 are not exceeded.

6.2.2Preventive maintenance

No routine scheduled preventive maintenance shall be required.

Cheetah 15K.5 SCSI Product Manual, Rev. J

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Contents Cheetah 15K.5 Scsi Page Contents Defect and error management InstallationInterface requirements List of Figures Page Seagate Online Support and Services Seagate Technology support servicesScope Standards Applicable standards and reference documentationElectromagnetic compatibility Electromagnetic susceptibilityEuropean Union Restriction of Hazardous Substances RoHS Electromagnetic complianceReference documents General description Drive model number vs. differentiating featuresMedia characteristics Standard featuresPerformance ReliabilityFormatted capacities Options factory installed Factory installed accessoriesAccessories Programmable drive capacityPerformance characteristics Internal drive characteristics transparent to userScsi performance characteristics visible to user Format command execution time minutes Generalized performance characteristicsSeek time Start/stop time Prefetch/multi-segmented cache controlCache operation Prefetch operation Caching write dataError rates Reliability specificationsRecoverable Errors Unrecoverable ErrorReliability and service Seek errorsPreventive maintenance 4 S.M.A.R.T Hot plugging Cheetah 15K.5 Scsi disc drivesPerformance impact Controlling S.M.A.R.TMilliseconds Reporting controlTemperature Log page 0Dh Parameter Code Description Thermal monitorDrive Self Test DST DST Failure Definition State of the drive prior to testingImplementation Invoking DSTShort test Function Code 001b Product warrantyExtended test Function Code 010b Log page entriesProduct repair and return information ShippingAC power requirements Physical/electrical specificationsDC power requirements ST3300655LC DC power requirementsST373455LC DC power requirements ST3146855LC DC power requirementsPower sequencing Conducted noise immunityCurrent profile Typical ST3300655LW drive +12V LVD current profile ST3300655LW/ST3300655LC Power dissipationST3146855LW/ST3146855LC ST3146855LC DC current and power vs. Iops LVDST373455LW/ST373455LC ST373455LC DC current and power vs. Iops LVDEnvironmental limits Temperature a. OperatingRelative humidity Effective altitude sea level a. OperatingShock Shock and vibrationRecommended mounting Air cleanliness Vibration a. Operating-normalCorrosive environment Acoustics Mechanical specificationsLC mounting configuration dimensions Defect and error management Drive error recovery proceduresDrive internal defects Read and write retry count maximum recovery times Scsi systems errors Background Media ScanMedia Pre-Scan Idle Read After Write Deferred Auto-ReallocationConfigure drive options InstallationDrive ID/option select header FormattingJ5 jumper header on LW models only Drive Front RES Function descriptionCooling Drive orientationGrounding Drive mountingGeneral description Interface requirementsScsi interface messages supported Scsi messages supported by Cheetah 15K.5 Scsi family drivesCommands supported by Cheetah 15K.5 Scsi family drive Scsi interface commands supportedCommands supported by Cheetah 15K.5 Scsi family drive Commands supported by Cheetah 15K.5 Scsi family drive Commands supported by Cheetah 15K.5 Scsi family drive Inquiry Vital Product data Cheetah 15K.5 Scsi family drive Standard Inquiry dataMode Sense data Mode Sense Pages Data ST3300655 Mode sense dataMode Sense Header Data Mode Sense Pages Data ST3146855 Mode sense dataST373455 Mode sense data Scsi bus conditions and other miscellaneous features Scsi bus conditions and miscellaneous features supportedPhysical interface Synchronous data transferDC cable and connector Scsi interface physical description Interface transfer rates supported Mating connectorsScsi interface cable requirements Cable requirementsMating connectors for LC model drives Mating connectors for LW model drivesScsi daisy-chain interface cabling for LW drives Right-angle to Pcba connectorsNonshielded 68-pin Scsi device connector used on LW drives Nonshielded 80-pin Scsi SCA-2 connector used on LC drives GND LW 68-conductor LVD P cable signal/pin assignments Active LED OUT 4 LC 80-pin single-ended SE I/O connector pin assignments+5 V Charge GND Active LED OUT 4 LC 80-pin single-ended LVD I/O connector pin assignmentsLVD output characteristics Electrical descriptionMultimode-SE and LVD alternatives General cable characteristics LVD Input characteristicsCable characteristics for single-ended circuits Single-ended drivers/receiversTwist-n-flat cables-into a multi-drive backplane Cables for low voltage differential drivers/receiversTerminator requirements Terminator power LW drivesLC drives Disc drive Scsi timing Disc drive Scsi timingDisc drive Scsi timing Drive activity LED Drive activity LED status Spindle status Command statusNumerics SymbolsPage Page Scsi Page Page