Seagate ST373453LC Reliability and service, Seek errors, Interface errors, Preventive maintenance

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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. The total error rate for a loop of devices is the sum of the individual device error rates.

5.2Reliability and service

You can enhance the reliability of Cheetah K15.4 disc drives by ensuring that the drive receives adequate cool- ing. 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 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 6.4.1 are not exceeded.

5.2.2Preventive maintenance

No routine scheduled preventive maintenance is required.

5.2.3Hot plugging the drive

Inserting and removing the drive on the FC-AL will interrupt loop operation. The interruption occurs when the receiver of the next device in the loop must synchronize to a different input signal. FC error detection mecha- nisms, character sync, running disparity, word sync, and CRC are able to detect any error. Recovery is initiated based on the type of error.

The disc drive defaults to the FC-AL Monitoring state, Pass-through state, when it is powered-on by switching the power or hot plugged. The control line to an optional port bypass circuit (external to the drive), defaults to the Enable Bypass state. If the bypass circuit is present, the next device in the loop will continue to receive the output of the previous device to the newly inserted device. If the bypass circuit is not present, loop operation is temporarily disrupted until the next device starts receiving the output from the newly inserted device and regains synchronization to the new input.

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Cheetah 15K.5 FC Product Manual, Rev. F

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Contents Cheetah 15K.5 FC ST3300655FC ST3146855FC ST373455FCPage Contents Defect and error management InstallationInterface requirements Seagate Technology support services Cheetah 15K.5 FC Product Manual, Rev. F List of Figures Page Scope Cheetah 15K.5 FC Product Manual, Rev. F Applicable standards and reference documentation StandardsElectromagnetic compatibility Electromagnetic susceptibilityEuropean Union Restriction of Hazardous Substances RoHS Reference documents Ncits TR-20Cheetah 15K.5 FC Product Manual, Rev. F General description Standard features Media descriptionPerformance ReliabilityFormatted capacities Programmable drive capacityFactory-installed accessories Factory-installed optionsUser-installed accessories Performance characteristics Internal drive characteristicsSeek performance characteristics Access timeFormat command execution time minutes General performance characteristicsStart/stop time Prefetch/multi-segmented cache controlCache operation Caching write dataPrefetch operation Reliability specifications Error ratesRecoverable Errors Unrecoverable ErrorsReliability and service Seek errorsInterface errors Preventive maintenance4 S.M.A.R.T Controlling S.M.A.R.TPerformance impact MillisecondsReporting control Determining ratePredictive failures Thermal monitorState of the drive prior to testing Parameter Code DescriptionDrive Self Test DST DST failure definitionInvoking DST Short and extended testsShort test Function Code 001b Extended test Function Code 010bProduct warranty AbortShipping Product repair and return informationCheetah 15K.5 FC Product Manual, Rev. F Physical/electrical specifications AC power requirementsDC power requirements DC power requirements for ST3300655FC model Gbit AmpsDC power requirements for ST3146855FC model Gbit Amps DC power requirements for ST373455FC model Gbit AmpsGeneral DC power requirement notes Power sequencingConducted noise immunity Current profilesTypical ST3300655FC drive, 4 Gbit, +12V current profile Typical ST3146855FC drive, 4 Gbit, +12V current profile Typical ST373455FC drive, 4 Gbit, +12V current profile Power dissipation ST3300655FCST3146855FC CURRENT/POWER vs Throughput FC 4GB ST3146855FCTemperature ST373455FC CURRENT/POWER vs Throughput FC 4GBEnvironmental limits ST373455FCRelative humidity Effective altitude sea levelShock and vibration ShockPackage size Packaged/product weight Drop height Recommended mounting Air cleanliness VibrationAcoustics Corrosive environmentRoHS compliance statement Mechanical specifications Mounting configuration dimensionsCheetah 15K.5 FC Product Manual, Rev. F Defect and error management Drive internal defects/errorsDrive error recovery procedures Page FC-AL system errors Background Media ScanMedia Pre-Scan Deferred Auto-ReallocationIdle Read After Write Installation Drive ID/option selectionDrive orientation CoolingDrive mounting Air flowGrounding Cheetah 15K.5 FC Product Manual, Rev. F FC-AL features Fibre Channel link service framesLink services supported Type of frame Interface requirementsFibre Channel task management functions Fibre Channel task management responsesFC Scsi FCP response codes Function name Response code Fibre Channel port login NPort login Plogi payload BytesFibre Channel port login accept Fibre Channel Process LoginNPort Login Accept ACC payload Bytes Process Login Plri payloadFibre Channel Process Login Accept Fibre Channel fabric loginProcess Login Accept ACC payload Bytes Fabric Login Flogi payload BytesFibre Channel fabric accept login Fabric Login Accept ACC payload BytesDual port support Fibre Channel Arbitrated Loop optionsFC-AL options supported Option SupportedScsi commands supported Supported commands Command code Command nameVerify error recovery page 07h Cheetah 15K.5 FC Product Manual, Rev. F Temperature page 0Dh Mode Sense data Inquiry dataCheetah 15K.5 FC inquiry data Bytes Data hex Page Mmode Sense 10 Byte Header Data Mode Sense 10 Byte Header Data 00 ae 00 10 00 00 00 08 08 8b b9 98 00 00 02 Miscellaneous operating features and conditions Miscellaneous featuresSupported Feature or condition Miscellaneous statusPhysical characteristics FC-AL physical interfacePhysical description Connector requirements Electrical descriptionPin descriptions FC-SCA pin descriptions Pin Signal name Signal type Pin Signal name Signal typeFC-AL transmitters and receivers Power Fault LED OutEnable port bypass signals Active LED OutMotor start controls Parallel Enclosure Services Interface ESI 11 SEL6 through SEL0 ID linesSetting Arbitrated loop physical address Alpa valuesHex Dec Signal characteristics TTL input characteristicsDevice control codes LED driver signals FC Differential outputFC Differential input Receive eye diagram Eye diagram data values Link rate GHz Cheetah 15K.5 FC Product Manual, Rev. F Seagate Technology support services InternetPresales Support Technical SupportWarranty Service Data Recovery Services Authorized Service CentersData Recovery Services Call Center Toll-free Direct dial Index NumericsFAN Flogi Plogi Page See also cooling
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