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Seagate ST400FM0012, ST100FM0012 Levels of PI, Setting and determining the current Type Level

Models: ST800FM0002 ST100FM0002 ST200FM0002 ST400FM0012 ST800FM0032 ST200FM0042 ST200FM0012 ST100FM0052 ST400FM0002 ST400FM0042 ST800FM0012 ST100FM0012

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9.6PROTECTION 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 formatted drives are physically formatted to 520 byte LBA’s 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 managed 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.

9.6.1Levels 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 WRTPROTECT 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 Protection Information are transmitted at LBA boundaries across the interface if RDPROTECT and WRTPROTECT 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 of Protection Information (e.g. 0xFFFFFFFF) to be stored on the media, but the 8 bytes will not be transferred to the host during a READ command.

Type 3 - Seagate products do not support Type 3.

9.6.2Setting and determining the current Type Level

A drive is initialized to a type of PI by using the FORMAT UNIT command on a PI capable drive. Once a drive is formatted 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. A drive can only be formatted to a single PI Type. It can be changed at anytime to a new Type but requires a FORMAT UNIT command 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 UNIT CDB command: 04 90 00 00 00 00, parameter data: 00 A0 00 00

Type 2 PI FORMAT UNIT CDB command: 04 D0 00 00 00 00, parameter data: 00 A0 00 00

9.6.3Identifying a Protection Information drive

The Standard INQUIRY data 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 Standard documentation.

PULSAR.2 SAS PRODUCT MANUAL, REV. C

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Seagate ST400FM0012, ST100FM0012, ST100FM0052, ST100FM0002 manual Levels of PI, Setting and determining the current Type Level
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ST800FM0002, ST100FM0002, ST200FM0002, ST400FM0012, ST800FM0032 specifications

The Seagate ST100FM0012, ST800FM0012, ST400FM0042, ST400FM0002, and ST100FM0052 are high-performance hard drives designed for enterprise applications, offering advanced features and reliability for demanding workloads.

The ST100FM0012 is a 10TB hard drive that strikes a balance between capacity and performance. It utilizes a 7200 RPM spindle speed and features a 256MB cache, enabling efficient data access and enhanced read/write performance. With Seagate’s AgileArray technology, the ST100FM0012 is optimized for NAS environments, providing multi-drive reliability and error recovery.

The ST800FM0012 is an 8TB variant that shares many features with its 10TB counterpart but is tailored for organizations needing robust storage without reaching the highest tier of capacity. Its dual-plane rotational vibration technology minimizes vibration in multi-drive systems, ensuring sustained performance over prolonged use. This makes it an excellent choice for virtualization and data-intensive applications.

The ST400FM0042 offers a 4TB capacity suited for smaller enterprise needs or as a backup solution. With an impressive performance profile, including a 7200 RPM speed and 128MB cache, it accommodates both sequential and random workloads with ease. This drive stands out with its PowerChoice technology, allowing users to manage power consumption and reduce operational costs.

Another 4TB option, the ST400FM0002, is particularly designed for hybrid configurations, pairing the fast access of the hard drive with the speed of SSDs. It features Seagate's advanced thermal management technologies, ensuring optimal operating temperatures and performance stability during intensive workloads.

The ST100FM0052 rounds out the lineup with a 10TB capacity but is specifically aimed at surveillance applications. It supports a workload rate of 180TB per year, making it ideal for always-on recording scenarios. The drive is built with optimized firmware, which ensures enhanced performance in write-intensive environments, essential for video recording and security systems.

All these drives are equipped with Seagate’s proprietary technologies, including data recovery services and built-in data protection features, ensuring data integrity and security. The drives are built for durability, reliability, and high performance in mission-critical environments, making them indispensable components of modern enterprise data storage solutions. With capacities ranging from 4TB to 10TB, they cater to varying storage needs across different sectors.