Seagate ST9146753SS, ST9300653SS, ST9300553SS, ST9300453SS Protection Information PI, Levels of PI

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10.8Protection Information (PI)

Protection Information is intended as a standardized approach to system level LRC traditionally provided by systems using 520 byte formatted LBAs. Drives formatted with PI information provide the same, common LBA count (i.e. same capacity point) as non-PI formatted drives. Sequential performance of a PI drive will be reduced by approximately 1.56% due to the extra overhead of PI being transferred from the media that is not calculated as part of the data transferred to the host. To determine the full transfer rate of a PI drive, transfers should be calculated by adding the 8 extra bytes of PI to the transferred LBA length, i.e. 512 + 8 = 520. PI for- matted drives are physically formatted to 520 byte sectors that store 512 bytes of customer data with 8 bytes of Protection Information appended to it. The advantage of PI is that the Protection Information bits can be man- aged at the HBA and HBA driver level. Allowing a system that typically does not support 520 LBA formats to integrate this level of protection.

Protection Information is valid with any supported LBA size. 512 LBA size is used here as common example.

10.8.1Levels of PI

There are 4 types of Protection Information.

Type 0 - Describes a drive that is not formatted with PI information bytes. This allows for legacy support in non- PI systems.

Type 1 - Provides support of PI protection using 10 and 16 byte commands. The RDPROTECT and WRTPRO- TECT bits allow for checking control through the CDB. Eight bytes of Protection Information are transmitted at LBA boundaries across the interface if RDPROTECT and WRTPROTECT bits are nonzero values. Type 1 does not allow the use of 32 byte commands.

Type 2 - Provides checking control and additional expected fields within the 32 byte CDBs. Eight bytes of Pro- tection Information are transmitted at LBA boundaries across the interface if RDPROTECT and WRTPRO- TECT bits are nonzero values. Type 2 does allow the use of 10 and 16 byte commands with zero values in the RDPROTECT and WRTPROTECT fields. The drive will generate 8 bytes (e.g.0xFFFF) 8 bytes of Protection Information to be stored on the media, but the 8 bytes will not be transferred to the host during a read com- mand.

Type 3 - Seagate products do not support Type 3.

10.8.2Setting and determining the current Type Level

A drive is initialized to a type of PI by using the format command on a PI capable drive. Once a drive is format- ted to a PI Type, it may be queried by a Read Capacity (16) command to report the PI type which it is currently formatted to. PI Types cannot coexist on a single drive. A drive can only be formatted to a single PI Type. It can be changed at anytime to a new Type but requires a low level format which destroys all existing data on the drive. No other vehicle for changing the PI type is provided by the T10 SBC3 specification.

Type 1 PI format CDB command:

04

90 00 00 00 00,

Write Buffer: 00 A0 00 00

Type 2 PI format CDB command:

04

D0 00 00 00 00,

Write Buffer: 00 A0 00 00

10.8.3Identifying a Protection Information drive

The Standard Inquiry provides a bit to indicate if PI is support by the drive. Vital Product Descriptor (VPD) page 0x86 provides bits to indicate the PI Types supported and which PI fields the drive supports checking.

Note. For further details with respect to PI, please refer to SCSI Block Commands - 3 (SBC-3) Draft Stan- dard documentation.

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Contents SED FIPS140-2 Models ST9300653SSST9300553SS ST9146853SSST9146753SSST9300453SS ST9146653SS Standard Models Self-Encrypting Drive ModelsPage Contents Interface requirements Defect and error managementInstallation About Fips About self-encrypting drivesPage Savvio 15K.3 SAS Product Manual, Rev. a List of Figures Page Seagate Online Support and Services Seagate Technology support servicesScope Electromagnetic susceptibility Applicable standards and reference documentationStandards Electromagnetic compatibilityKorean KCC Electromagnetic complianceElectromagnetic compliance for the European Union Australian C-TickEuropean Union Restriction of Hazardous Substances RoHS Reference documents Scsi Commands Reference Manual SAS Interface ManualGeneral description Media description Standard featuresPerformance ReliabilityFormatted capacities Programmable drive capacity Factory installed optionsAccess time Performance characteristicsInternal drive characteristics Seek performance characteristicsFormat command execution time General performance characteristicsStart/stop time Cache operation Prefetch/multi-segmented cache controlPrefetch operation Caching write dataUnrecoverable Errors Reliability specificationsError rates Recoverable ErrorsPreventive maintenance Reliability and serviceSeek errors Interface errorsPerformance impact Maximum processing delay4 S.M.A.R.T Controlling S.M.A.R.TTemperature Log Page 0Dh Parameter Code Description Predictive failuresThermal monitor Implementation State of the drive prior to testingDrive Self Test DST DST failure definitionLog page entries Short and extended testsShort test Function Code 001b Extended test Function Code 010bStorage Product warrantyShipping Product repair and return informationPhysical/electrical specifications PowerChoiceTM power managementPowerChoice modes DC power requirements AC power requirementsRegulation 300GB models DC power requirements146GB models DC power requirements General DC power requirement notes Power sequencingConducted noise immunity Current profile for 300GB models Current profilesCurrent profile for 146GB models Power dissipation 300GB models in 6Gb operation300GB models in 3Gb operation 146GB models in 3Gb operation 146GB models in 6Gb operationTemperature a. Operating Environmental limitsRelative humidity Effective altitude sea level a. Operating Shock and vibrationShock Recommended mounting Vibration a. Operating-normalAir cleanliness Corrosive environmentAcoustics Dimensions Mechanical specificationsAbout Fips PurposeLevel 2 security Data encryption Controlled accessAdmin SP About self-encrypting drivesData bands Default passwordRandom number generator RNG Drive lockingCryptographic erase Authenticated firmware downloadPower requirements Supported commandsDefect and error management Drive internal defects/errorsDrive error recovery procedures Background Media Scan SAS system errorsMedia Pre-Scan Deferred Auto-ReallocationIdle Read After Write Identifying a Protection Information drive Setting and determining the current Type LevelProtection Information PI Levels of PIDrive orientation InstallationAir flow CoolingGrounding Drive mountingInterface requirements SAS featuresScsi commands supported Supported commandsDual port support Supported commands Supported commands Supported commands Mode Sense data Inquiry dataSavvio inquiry data Page Mode Data Header Mode Data Header Miscellaneous operating features and conditions Miscellaneous featuresMiscellaneous status SAS physical interface Datum B Section C C Section a a Pin descriptions Physical characteristicsConnector requirements Electrical descriptionReady LED Out Signal characteristicsPower SAS transmitters and receiversGeneral interface characteristics SAS-2 Specification complianceLED drive signal Differential signalsNumerics IndexPage Msid Mtbf See also cooling Page Savvio 15K.3 SAS Product Manual, Rev. a
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