Seagate ST373453LC manual FC-AL system errors, Background Media Scan

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Table 5: Read and write retry count maximum recovery times [1]

Read retry

Maximum recovery time per LBA

count

(cumulative, msec)

 

 

0

51.87

 

 

1

59.85

 

 

2

203.49

 

 

3

219.45

 

 

4

253.11

 

 

5

279.35

 

 

6

311.27

 

 

7

395.12

 

 

8

463.12

 

 

9

495.04

 

 

10

530.95

 

 

11 (default)

1,282.97

 

 

[1]These values are subject to change.

Write retry

Maximum recovery time per LBA

count

(cumulative, msec)

 

 

0

23.94

 

 

1

35.91

 

 

2

55.86

 

 

3

67.83

 

 

4

119.79

 

 

5 (default)

147.72

 

 

Setting these retry counts to a value below the default setting could result in an increased unrecovered error rate which may exceed the value given in this product manual. A setting of zero (0) will result in the drive not performing error recovery.

For example, suppose the Read/Write Recovery page has the RC bit set to 0, read retry count set to 4, and the recovery time limit field (Mode Sense page 01, bytes 10 and 11) set to FF FF hex (maximum). A four LBA Read command is allowed to take up to 253.11 msec recovery time for each of the four LBAs in the command. If the recovery time limit is set to 00 C8 hex (200 msec decimal) a four LBA read command is allowed to take up to 200 msec for all error recovery within that command. The use of the Recovery Time Limit field allows finer granularity on control of the time spent in error recovery. The recovery time limit only starts counting when the drive is executing error recovery and it restarts on each command. Therefore, each command’s total recovery time is subject to the recovery time limit. Note: A recovery time limit of 0 will use the drive’s default value of FF FF. Minimum recovery time limit is achieved by setting the Recovery Time Limit field to 00 01.

7.3FC-AL system errors

Information on the reporting of operational errors or faults across the interface is given in the Fibre Channel Interface Manual. The FCP Response returns information to the host about numerous kinds of errors or faults. The Receive Diagnostic Results reports the results of diagnostic operations performed by the drive.

Status returned by the drive to the initiator is described in the Fibre Channel Interface Manual. Status reporting plays a role in systems error management and its use in that respect is described in sections where the various commands are discussed.

7.4Background Media Scan

Background Media Scan (BMS) is a self-initiated media scan. BMS is defined in the T10 document SPC-4 available from the T10 committee. BMS performs sequential reads across the entire pack of the media while the drive is idle. In RAID arrays, BMS allows hot spare drives to be scanned for defects prior to being put into service by the host system. On regular duty drives, if the host system makes use of the BMS Log Page, it can avoid placing data in suspect locations on the media. Unreadable and recovered error sites will be logged or reallocated per ARRE/AWRE settings.

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

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Contents ST3300655FC ST3146855FC ST373455FC Cheetah 15K.5 FCPage Contents Installation Defect and error managementInterface 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 Standards Applicable standards and reference documentationElectromagnetic compatibility Electromagnetic susceptibilityEuropean Union Restriction of Hazardous Substances RoHS Ncits TR-20 Reference documentsCheetah 15K.5 FC Product Manual, Rev. F General description Media description Standard featuresReliability PerformanceFormatted capacities Programmable drive capacityFactory-installed options Factory-installed accessoriesUser-installed accessories Internal drive characteristics Performance characteristicsSeek performance characteristics Access timeGeneral performance characteristics Format command execution time minutesStart/stop time Prefetch/multi-segmented cache controlCaching write data Cache operationPrefetch operation Error rates Reliability specificationsRecoverable Errors Unrecoverable ErrorsSeek errors Reliability and serviceInterface errors Preventive maintenanceControlling S.M.A.R.T 4 S.M.A.R.TPerformance impact MillisecondsDetermining rate Reporting controlPredictive failures Thermal monitorParameter Code Description 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 warrantyShipping Product repair and return informationCheetah 15K.5 FC Product Manual, Rev. F AC power requirements Physical/electrical specificationsDC power requirements DC power requirements for ST3300655FC model Gbit AmpsDC power requirements for ST373455FC model Gbit Amps DC power requirements for ST3146855FC model Gbit AmpsPower sequencing General DC power requirement notesConducted 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 ST3300655FC Power dissipationST3146855FC ST3146855FC CURRENT/POWER vs Throughput FC 4GBST373455FC CURRENT/POWER vs Throughput FC 4GB TemperatureEnvironmental limits ST373455FCEffective altitude sea level Relative humidityShock and vibration ShockPackage size Packaged/product weight Drop height Recommended mounting Vibration Air cleanlinessAcoustics Corrosive environmentRoHS compliance statement Mounting configuration dimensions Mechanical specificationsCheetah 15K.5 FC Product Manual, Rev. F Drive internal defects/errors Defect and error managementDrive error recovery procedures Page Background Media Scan FC-AL system errorsDeferred Auto-Reallocation Media Pre-ScanIdle Read After Write Drive ID/option selection InstallationDrive orientation CoolingAir flow Drive mountingGrounding Cheetah 15K.5 FC Product Manual, Rev. F Fibre Channel link service frames FC-AL featuresLink services supported Type of frame Interface requirementsFibre Channel task management responses Fibre Channel task management functionsFC Scsi FCP response codes Function name Response code 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 Cheetah 15K.5 FC Product Manual, Rev. F Temperature page 0Dh Inquiry data Mode Sense 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 features Miscellaneous operating features and conditionsSupported Feature or condition Miscellaneous statusFC-AL physical interface Physical characteristicsPhysical description Electrical description Connector requirementsPin descriptions Pin Signal name Signal type FC-SCA pin descriptions Pin Signal name Signal typeFC-AL transmitters and receivers Fault LED Out PowerActive LED Out Enable port bypass signalsMotor start controls 11 SEL6 through SEL0 ID lines Parallel Enclosure Services Interface ESIArbitrated loop physical address Alpa values SettingHex Dec TTL input characteristics Signal characteristicsDevice control codes FC Differential output LED driver signalsFC Differential input Receive eye diagram Eye diagram data values Link rate GHz Cheetah 15K.5 FC Product Manual, Rev. F Internet Seagate Technology support servicesPresales Support Technical SupportData Recovery Services Authorized Service Centers Warranty ServiceData Recovery Services Call Center Toll-free Direct dial Numerics IndexFAN Flogi Plogi Page See also cooling
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