Seagate CONSTELLATION SAS User Manual

Product Manual

Constellation® SAS

Standard Models

ST9500430SS

Self-Encrypting Drive Models

ST9500431SS

100538693
Rev. C
May 2009

Revision history

Revision Date Sheets affected or comments

Rev. A 02/03/09 Initial release.
Rev. B 03/05/09 Added ST9500431SS SED model.
Rev. C 06/11/09 2-7, 10, 17, 20-23, 26-28, 45, 47. 50 and 58.

©2009, Seagate Technology LLC All rights reserved.

Publication number: 100538693, Rev. C May 2009

Seagate, Seagate Technology and the Wave logo are registered trademarks of Seagate Technology LLC
in the United States and/or other countries. Constellation, SeaTools and SeaTDD are either trademarks or
registered trademarks of Seagate Technology LLC or one of its affiliated companies in the United States
and/or other countries. All other trademarks or registered trademarks are the property of their respective
owners.

When referring to hard drive capacity, one gigabyte, or GB, equals one billion bytes and one terabyte, or
TB, equals one trillion bytes. Your computer's operating system may use a different standard of measure
ment and report a lower capacity. In addition, some of the listed capacity is used for formatting and other
functions, and thus will not be available for data storage. Quantitative usage examples for various applica
tions are for illustrative purposes. Actual quantities will vary based on various factors, including file size,
file format, features and application software. Seagate reserves the right to change, without notice, product
offerings or specifications.

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Contents

1.0 Scope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2.0 Applicable standards and reference documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2.1 Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2.1.1 Electromagnetic compatibility. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2.1.2 Electromagnetic compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2.1.3 European Union Restriction of Hazardous Substances (RoHS) . . . . . . . . . . . . . 4

2.2 Reference documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3.0 General description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.1 Standard features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

3.2 Media description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

3.3 Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3.4 Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3.5 Formatted capacities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3.6 Programmable drive capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3.7 Factory-installed options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

4.0 Performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4.1 Internal drive characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4.2 Seek performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4.2.1 Access time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4.2.2 Format command execution time for 512-byte sectors (minutes) . . . . . . . . . . . 10

4.2.3 General performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.3 Start/stop time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.4 Prefetch/multi-segmented cache control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

4.5 Cache operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

4.5.1 Caching write data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

4.5.2 Prefetch operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

5.0 Reliability specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

5.1 Error rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

5.1.1 Recoverable Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

5.1.2 Unrecoverable Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

5.1.3 Seek errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

5.1.4 Interface errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

5.2 Reliability and service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

5.2.1 Annualized Failure Rate (AFR) and Mean Time Between Failure (MTBF) . . . . 14

5.2.2 Preventive maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

5.2.3 Hot plugging the drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

5.2.4 S.M.A.R.T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

5.2.5 Thermal monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

5.2.6 Drive Self Test (DST) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

5.2.7 Product warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

6.0 Physical/electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

6.1 PowerChoiceTM power management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

6.1.1 PowerChoice reporting methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

6.2 AC power requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

6.3 DC power requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

6.3.1 Conducted noise immunity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

6.3.2 Power sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

6.3.3 Current profiles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

6.4 Power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

6.5 Environmental limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Constellation SAS Product Manual, Rev. C i

6.5.1 Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

6.5.2 Relative humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

6.5.3 Effective altitude (sea level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

6.5.4 Shock and vibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

6.5.5 Air cleanliness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

6.5.6 Corrosive environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

6.5.7 Acoustics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

6.5.8 Electromagnetic susceptibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

6.6 Mechanical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

7.0 About self-encrypting drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

7.1 Data encryption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

7.2 Controlled access. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

7.2.1 Admin SP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

7.2.2 Locking SP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

7.2.3 Default password . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

7.3 Random number generator (RNG). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

7.4 Drive locking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

7.5 Data bands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

7.6 Cryptographic erase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

7.7 Authenticated firmware download . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

7.8 Power requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

7.9 Supported commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

8.0 Defect and error management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

8.1 Drive internal defects/errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

8.2 Drive error recovery procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

8.3 SAS system errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.4 Background Media Scan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

8.5 Media Pre-Scan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

8.6 Deferred Auto-Reallocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

8.7 Idle Read After Write . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

9.0 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

9.1 Drive orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

9.2 Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

9.3 Drive mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

9.4 Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

10.0 Interface requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

10.1 SAS features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

10.1.1 task management functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

10.1.2 task management responses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

10.2 Dual port support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

10.3 SCSI commands supported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

10.3.1 Inquiry data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

10.3.2 Mode Sense data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

10.4 Miscellaneous operating features and conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

10.4.1 SAS physical interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

10.4.2 Physical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

10.4.3 Connector requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

10.4.4 Electrical description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

10.4.5 Pin descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

10.4.6 SAS transmitters and receivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

10.4.7 Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

10.5 Signal characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

10.5.1 Ready LED Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

ii Constellation SAS Product Manual, Rev. C

10.5.2 Differential signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

10.6 SAS-2 Specification Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

10.7 Additional information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

11.0 Seagate Technology support services. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Constellation SAS Product Manual, Rev. C iii

iv Constellation SAS Product Manual, Rev. C

List of Figures

Figure 1. ST9500430SS & ST9500431SS model current profiles 24

Figure 2. ST9500430SS & ST9500431SS (3 Gbit) DC current and power vs. input/output operations per second . . .25

Figure 3. ST9500430SS & ST9500431SS (6 Gbit) DC current and power vs. input/output operations per second . . .26

Figure 4. Location of the HDA temperature check point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

Figure 5. Recommended mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

Figure 6. Mounting configuration dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33

Figure 7. Physical interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

Figure 8. Air flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

Figure 9. Physical interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54

Figure 10. SAS device plug dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55

Figure 11. SAS device plug dimensions (detail) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56

Figure 12. SAS transmitters and receivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58

Constellation SAS Product Manual, Rev. C 1

2 Constellation SAS Product Manual, Rev. C

1.0 Scope

This manual describes Seagate Technology® LLC, Constellation® SAS (Serial Attached SCSI) disc drives.

Constellation drives support the SAS Protocol specifications to the extent described in this manual. The SAS
Interface Manual (part number 100293071) describes the general SAS characteristics of this and other Sea­gate SAS drives. The Self-Encrypting Drive Reference Manual, part number 100515636, describes the inter­face, general operation, and security features available on Self-Encrypting Drive models.

Note. Previous generations of Seagate Self-Encrypting Drive models were called Full Disk Encryption

(FDE) models before a differentiation between drive-based encryption and other forms of encryp
tion was necessary.

Product data communicated in this manual is specific only to the model numbers listed in this manual. The data
listed in this manual may not be predictive of future generation specifications or requirements. If you are
designing a system which will use one of the models listed or future generation products and need further
assistance, please contact your Field Applications Engineer (FAE) or our global support services group as
shown in Section 11.0.

Unless otherwise stated, the information in this manual applies to standard and Self-Encrypting Drive models.

Model Number Self-Encrypting Drive (SED)

ST9500430SS No

ST9500431SS Yes

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Constellation SAS Product Manual, Rev. C 1

2.0 Applicable standards and reference documentation

The drives documented in this manual have been developed as system peripherals to the highest standards of
design and construction. The drives depends on host equipment to provide adequate power and environment
for optimum performance and compliance with applicable industry and governmental regulations. Special
attention must be given in the areas of safety, power distribution, shielding, audible noise control, and temper­ature regulation. In particular, the drive must be securely mounted to guarantee the specified performance
characteristics. Mounting by bottom holes must meet the requirements of Section 9.3.

2.1 Standards

The Constellation family complies with Seagate standards as noted in the appropriate sections of this manual
and the Seagate SAS Interface Manual, part number 100293071.

The drives are recognized in accordance with UL 60950-1 as tested by UL, CSA 60950-1 as tested by CSA,
and EN60950-1 as tested by TUV.

The security features of Self-Encrypting Drive models are based on the “TCG Storage Architecture Core Spec­ification” and the “TCG Storage Workgroup Security Subsystem Class: Enterprise_A” specification with addi­tional vendor-unique features as noted in this product manual.

2.1.1 Electromagnetic compatibility

The drive, as delivered, is designed for system integration and installation into a suitable enclosure prior to
use. The drive is supplied as a subassembly and is not subject to Subpart B of Part 15 of the FCC Rules and
Regulations nor the Radio Interference Regulations of the Canadian Department of Communications.

The design characteristics of the drive serve to minimize radiation when installed in an enclosure that provides
reasonable shielding. The drive is capable of meeting the Class B limits of the FCC Rules and Regulations of
the Canadian Department of Communications when properly packaged; however, it is the user’s responsibility
to assure that the drive meets the appropriate EMI requirements in their system. Shielded I/O cables may be
required if the enclosure does not provide adequate shielding. If the I/O cables are external to the enclosure,
shielded cables should be used, with the shields grounded to the enclosure and to the host controller.

2.1.1.1 Electromagnetic susceptibility

As a component assembly, the drive is not required to meet any susceptibility performance requirements. It is
the responsibility of those integrating the drive within their systems to perform those tests required and design
their system to ensure that equipment operating in the same system as the drive or external to the system
does not adversely affect the performance of the drive. See Table 2, DC power requirements.

2 Constellation SAS Product Manual, Rev. C

2.1.2 Electromagnetic compliance

Seagate uses an independent laboratory to confirm compliance with the directives/standards for CE Marking
and C-Tick Marking. The drive was tested in a representative system for typical applications. The selected sys­tem represents the most popular characteristics for test platforms. The system configurations include:

• Typical current use microprocessor

• Keyboard

• Monitor/display

• Printer

•Mouse

Although the test system with this Seagate model complies with the directives/standards, we cannot guarantee
that all systems will comply. The computer manufacturer or system integrator shall confirm EMC compliance
and provide the appropriate marking for their product.

Electromagnetic compliance for the European Union

If this model has the CE Marking it complies with the European Union requirements of the Electromagnetic
Compatibility Directive 2004/108/EC as put into place on 20 July 2007.

Australian C-Tick

If this model has the C-Tick Marking it complies with the Australia/New Zealand Standard AS/NZ CISPR22 and
meets the Electromagnetic Compatibility (EMC) Framework requirements of Australia’s Spectrum Manage­ment Agency (SMA).

Korean KCC

If these drives have the Korean Communications Commission (KCC) logo, they comply with paragraph 1 of
Article 11 of the Electromagnetic Compatibility control Regulation and meet the Electromagnetic Compatibility
(EMC) Framework requirements of the Radio Research Laboratory (RRL) Communications Commission,
Republic of Korea.

These drives have been tested and comply with the Electromagnetic Interference/Electromagnetic
Susceptibility (EMI/EMS) for Class B products. Drives are tested in a representative, end-user system by a
Korean-recognized lab.

• Family name: Constellation

• Certificate number: STX-ST9500430SS (B)

Taiwanese BSMI

If this model has two Chinese words meaning “EMC certification” followed by an eight digit identification num­ber, as a Marking, it complies with Chinese National Standard (CNS) 13438 and meets the Electromagnetic
Compatibility (EMC) Framework requirements of the Taiwanese Bureau of Standards, Metrology, and Inspec­tion (BSMI).

Constellation SAS Product Manual, Rev. C 3

2.1.3 European Union Restriction of Hazardous Substances (RoHS)

The European Union Restriction of Hazardous Substances (RoHS) Directive, restricts the presence of chemi­cal substances, including Lead, Cadmium, Mercury, Hexavalent Chromium, PBB and PBDE, in electronic prod­ucts, effective July 2006. This drive is manufactured with components and materials that comply with the RoHS
Directive.

A number of parts and materials in Seagate products are procured from external suppliers. We rely on the rep­resentations of our suppliers regarding the presence of RoHS substances in these parts and materials. Our
supplier contracts require compliance with our chemical substance restrictions, and our suppliers document
their compliance with our requirements by providing material content declarations for all parts and materials for
the disc drives documented in this publication. Current supplier declarations include disclosure of the inclusion
of any RoHS-regulated substance in such parts or materials.

Seagate also has internal systems in place to ensure ongoing compliance with the RoHS Directive and all laws
and regulations which restrict chemical content in electronic products. These systems include standard operat­ing procedures that ensure that restricted substances are not utilized in our manufacturing operations, labora­tory analytical validation testing, and an internal auditing process to ensure that all standard operating
procedures are complied with.

2.2 Reference documents

SAS Interface Manual

SCSI Commands Reference Manual

Self-Encrypting Drives Reference Manual

ANSI SAS Documents

ANSI Small Computer System Interface (SCSI) Documents

Trusted Computing Group (TCG) Documents (apply to Self-Encrypting Drive models only)

Specification for Acoustic Test Requirement and Procedures

Seagate part number: 100293071

Seagate part number: 100293068

Seagate part number: 100515636

SFF-82232.5” Drive Form Factor with Serial Connector
SFF-8460HSS Backplane Design Guidelines
SFF-8470Multi Lane Copper Connector
SFF-8482SAS Plug Connector
ANSI INCITS.xxx Serial Attached SCSI (SAS) Standard (T10/1562-D)
ISO/IEC 14776-xxxSCSI Architecture Model-3 (SAM-3) Standard (T10/1561-D)
ISO/IEC 14776-xxxSCSI Primary Commands-3 (SPC-3) Standard (T10/1416-D)
ISO/IEC 14776-xxxSCSI Block Commands-2 (SBC-2) Standard (T10/1417-D)

X3.270-1996(SCSI-3) Architecture Model

TCG Storage Architecture Core Specification, Rev. 1.0
TCG Storage Security Subsystem Class Enterprise Specification, Rev. 1.0

Seagate part number: 30553-001

Package Test Specification Seagate P/N 30190-001 (under 100 lb.)
Package Test Specification Seagate P/N 30191-001 (over 100 lb.)

In case of conflict between this document and any referenced document, this document takes precedence.

4 Constellation SAS Product Manual, Rev. C

3.0 General description

Constellation drives provide high performance, high capacity data storage for a variety of systems including
engineering workstations, network servers, mainframes, and supercomputers. The Serial Attached SCSI inter­face is designed to meet next-generation computing demands for performance, scalability, flexibility and high­density storage requirements.

Constellation drives are random access storage devices designed to support the Serial Attached SCSI Proto­col as described in the ANSI specifications, this document, and the SAS Interface Manual (part number

100293071) which describes the general interface characteristics of this drive. Constellation drives are classi­fied as intelligent peripherals and provide level 2 conformance (highest level) with the ANSI SCSI-1 standard.
The SAS connectors, cables and electrical interface are compatible with Serial ATA (SATA), giving future users
the choice of populating their systems with either SAS or SATA hard disc drives. This allows you to continue to
leverage your existing investment in SCSI while gaining a 6Gb/s serial data transfer rate.

The Self-Encrypting Drive models indicated on the cover of this product manual have provisions for “Security
of Data at Rest” based on the standards defined by the Trusted Computing Group (see www.trustedcomputing­group.org).

The head and disc assembly (HDA) is sealed at the factory. Air recirculates within the HDA through a non­replaceable filter to maintain a contamination-free HDA environment.

Note. Never disassemble the HDA and do not attempt to service items in the sealed enclosure (heads,

media, actuator, etc.) as this requires special facilities. The drive does not contain user-replaceable
parts. Opening the HDA for any reason voids your warranty.

Constellation drives use a dedicated load/unload zone at the outermost radius of the media to eliminate the
possibility of destroying or degrading data by landing in the data zone. The heads automatically go to the ramp
load/unload when power is removed from the drive.

An automatic shipping lock prevents potential damage to the heads and discs that results from movement dur­ing shipping and handling. The shipping lock disengages and the head load process begins when power is
applied to the drive.

Constellation drives decode track 0 location data from the servo data embedded on each surface to eliminate
mechanical transducer adjustments and related reliability concerns.

The drives also use a high-performance actuator assembly with a low-inertia, balanced, patented, straight arm
design that provides excellent performance with minimal power dissipation.

Constellation SAS Product Manual, Rev. C 5

3.1 Standard features

Constellation drives have the following standard features:

• Perpendicular recording technology

• 1.5 / 3 / 6 Gbit Serial Attached SCSI (SAS) interface

• Integrated dual port SAS controller supporting the SCSI protocol

• Support for SAS expanders and fanout adapters

• Firmware downloadable using the SAS interface

• 128 - deep task set (queue)

• Supports up to 32 initiators

• Jumperless configuration.

• User-selectable logical block size (512, 520 or 528 bytes per logical block).

• Industry standard SFF 2.5-inch dimensions

• Programmable logical block reallocation scheme

• Flawed logical block reallocation at format time

• Programmable auto write and read reallocation

• Reallocation of defects on command (Post Format)

• ECC maximum burst correction length of 520 bits

• No preventive maintenance or adjustments required

• Embedded servo design

• Automatic shipping lock

• Dedicated head load/unload zone

• Self diagnostics performed when power is applied to the drive

• Zone bit recording (ZBR)

• Vertical, horizontal, or top down mounting

• Dynamic spindle brake

• 16 Mbyte data buffer (see Section 4.5).

• Drive Self Test (DST)

• Background Media Scan (BMS)

• Idle Read After Write (IRAW)

•Power Save

Constellation® SAS Self-Encrypting Drive models have the following additional features:

• Automatic data encryption/decryption

• Controlled access

• Random number generator

• Drive locking

• 16 independent data bands

• Cryptographic erase of user data for a drive that will be repurposed or scrapped

• Authenticated firmware download

3.2 Media description

The media used on the drive has a glass substrate coated with a thin film magnetic material, overcoated with a
proprietary protective layer for improved durability and environmental protection.

6 Constellation SAS Product Manual, Rev. C

3.3 Performance

• Programmable multi-segmentable cache buffer

• 600 Mbytes/sec maximum instantaneous data transfers.

• 7,200 RPM spindle. Average latency = 4.16 msec

• Background processing of queue

• Supports start and stop commands (spindle stops spinning)

• Adaptive seek velocity; impr

oved seek performance

Note. Th

ere is no significant performance difference between Self-Encrypting Drive and standard (non-

Self-Encrypting Drive) models.

3.4 Reliability

• Annualized Failure Rate (AFR) of 0.73%

• Mean time between failures (MTBF) of 1,200,000 hours

• Balanced low mass rotary voice coil actuator

• Incorporates industry-standard Self-Monitoring Analysis

and Reporting Technology (S.M.A.R.T.)

• 5-year warranty

3.5 Formatted capacities

Standard OEM models are formatted to 512 bytes per block. The block size is selectable at format time and
must be a multiple of 4 bytes. Users having the necessary equipment may modify the data block size before
issuing a format command and obtain different formatted capacities than those listed.

To provide a stable target capacity environment and at the same time provide users with flexibility if they
choose, Seagate recommends product planning in one of two modes:

1. Seagate designs specify capacity points at certain blo
products will meet. We recommend customers use this capacity in their project planning, as it ensures a
stable operating point with backward and forward compatibility from generation to generation. The current
guaranteed operating points for this product are:

ck sizes that Seagate guarantees current and future

Capacity (Blocks)

ST9500430SS & ST9500431SS

Sector Size

Decimal Hex

512 976,773,168 3A386030

520 961,538,465 394FE9A1

528 938,165,665 37EB45A1

3.6 Programmable drive capacity

Using the Mode Select command, the drive can change its capacity to something less than maximum. See the
Mode Select (6) parameter list table in the SAS Interface Manual, part number 100293071. A value of zero in
the Number of Blocks field indicates that the drive will not change the capacity it is currently formatted to have.
A number other than zero and less than the maximum number of LBAs in the Number of Blocks field changes
the total drive capacity to the value in the Number of Blocks field. A value greater than the maximum number of
LBAs is rounded down to the maximum capacity.

Constellation SAS Product Manual, Rev. C 7

3.7 Factory-installed options

You may order the following items which are incorporated at the manufacturing facility during production or
packaged before shipping. Some of the options available are (not an exhaustive list of possible options):

• Other capacities can be ordered depending on sparing scheme and sector size requested.

• Single-unit shipping pack. The drive is normally shipped in bulk packaging to provide maximum protection
against transit damage. Units shipped individually require additional protection as provided by the single unit
shipping pack. Users planning single unit distribution should specify this option.

•The Safety and Regulatory Agency Specifications, part number 75789512, is usually included with each
standard OEM drive shipped, but extra copies may be ordered.

8 Constellation SAS Product Manual, Rev. C

4.0 Performance characteristics

This section provides detailed information concerning performance-related characteristics and features of Con­stellation drives.

4.1 Internal drive characteristics

ST9500430SS & ST9500431SS

Drive capacity 500 Gbytes (formatted, rounded off value)
Read/write data heads 6
Bytes per track 890,823 Bytes (average, rounded off values)
Bytes per surface 83,370 Mbytes (u
Tracks per surface (total) 123,148 Tracks (user accessible)
Tracks per inch 200,000 TPI (average)
Peak bits per inch 1,410,000 BPI
Areal density 283 Gbit/in
Internal data rate 75 - 142 Mbytes/sec (variable with zone)
Disc rotation speed 7,200 rpm
Avg rotational latency 4.16 msec

4.2 Seek performance characteristics

See Section 10.4.1, "SAS physical interface" on page 54 and the SAS Interface Manual (part number

100293071) for additional timing details.

nformatted, rounded off value)

2

4.2.1 Access time

1

Including controller overhead2

,

(msec)

Not including controller overhead
(msec)

1, 2

Read Write Read Write

Average Typica l

Single track Typical

Full stroke Typica l

,

3,4

3,4

8.2 8.6 8.0 8.4

0.5 0.7 0.5 0.7

17.55 18.02 17.35 17.82

43

1. Execution time measured from receipt of the Command to the Response.

2. Assumes no errors and no sector has been relocated.

3. Typical access times are measured under nominal conditions of temperature, voltage, and horizontal orientation as
measured on a representative sample of drives.

4. Access time = controller overhead + average seek time and applies to all data transfer commands.
Access to data = access time + latency time.

Constellation SAS Product Manual, Rev. C 9

4.2.2 Format command execution time for 512-byte sectors (minutes)

ST9500430SS & ST9500431SS

Maximum (with verify)

Maximum (without verify)

216

108

Note. Th

ere is no significant difference in the format time between SED and non-SED models of the

same capacity.

4.2.3 General performance characteristics

Minimum sector interleave 1 to 1

Data buffer to/from disc media (one 512-byte logical block)* 75 to 142 MBytes/sec

Sustained transfer rate 95 to 100 Mbytes/sec

SAS Interface maximum instant

Logical block sizes

512 (default), 520 or 528.

Read/write consecutive sectors on a track Yes

Flaw reallocation performance impact (for flaws reallocated at format time using the

are sectors per sparing zone reallocation scheme.)

sp

Average rotational latency 4.16 msec

*Assumes no errors and no relocated logical blocks. Rate measured from the start of the first logical block transfer to or
from the host.

aneous transfer rate 600 Mbytes/sec* per port

(dual port = 1200 Mbytes/sec*)

Negligible

4.3 Start/stop time

The drive accepts the commands listed in the SAS Interface Manual less than 3 seconds after DC power has
been applied.

If the drive receives a NOTIFY (ENABLE SPINUP) primitive through either port and has not received a START
STOP UNIT command with the START bit equal to 0, the drive becomes ready for normal operations within 30
seconds (excluding the error recovery procedure).

If the drive receives a START STOP UNIT command with the START bit equal to 0 before receiving a NOTIFY
(ENABLE SPINUP) primitive, the drive waits for a START STOP UNIT command with the START bit equal to 1.
After receiving a START STOP UNIT command with the START bit equal to 1, the drive waits for a NOTIFY
(ENABLE SPINUP) primitive. After receiving a NOTIFY (ENABLE SPINUP) primitive through either port, the
drive becomes ready for normal operations within 30 seconds (excluding the error recovery procedure).

If the drive receives a START STOP UNIT command with the START bit and IMMED bit equal to 1 and does
not receive a NOTIFY (ENABLE SPINUP) primitive within 5 seconds, the drive fails the START STOP UNIT
command.

The START STOP UNIT command may be used to command the drive to stop the spindle. Stop time is 20 sec­onds (maximum) from removal of DC power. SCSI stop time is 20 seconds. There is no power control switch
on the drive.

10 Constellation SAS Product Manual, Rev. C

4.4 Prefetch/multi-segmented cache control

The drive provides a prefetch (read look-ahead) and multi-segmented cache control algorithms that in many
cases can enhance system performance. Cache refers to the drive buffer storage space when it is used in
cache operations. To select this feature, the host sends the Mode Select command with the proper values in
the applicable bytes in page 08h. Prefetch and cache operations are independent features from the standpoint
that each is enabled and disabled independently using the Mode Select command; however, in actual opera­tion, the prefetch feature overlaps cache operation somewhat as described in sections 4.5.1 and 4.5.2.

All default cache and prefetch mode parameter values (Mode Page 08h) for standard OEM versions of this
drive family are given in Table 8.

4.5 Cache operation

Note. Refer to the SAS Interface Manual for more detail concerning the cache bits.

Of the 16 Mbytes physical buffer space in the drive, approximately 13,000 kbytes can be used as a cache. The
buffer is divided into logical segments from which data is read and to which data is written.

The drive keeps track of the logical block addresses of the data stored in each segment of the buffer. If the
cache is enabled (see RCD bit in the SAS Interface Manual ), data requested by the host with a read command
is retrieved from the buffer, if possible, before any disc access is initiated. If cache operation is not enabled, the
buffer is still used, but only as circular buffer segments during disc medium read operations (disregarding
Prefetch operation for the moment). That is, the drive does not check in the buffer segments for the requested
read data, but goes directly to the medium to retrieve it. The retrieved data merely passes through some buffer
segment on the way to the host. All data transfers to the host are in accordance with buffer-full ratio rules. See
the explanation provided with the information about Mode Page 02h (disconnect/reconnect control) in the SAS
Interface Manual.

The following is a simplified description of the prefetch/cache operation:

Case A—read command is received and all of the requested logical blocks are already in the cache:

1. Drive transfers the requested logical blocks to the initiator.

Case B—A Read command requests data, and at least one requested logical block is not in any segment of
the cache:

1. The drive fetches the requested logical blocks from the disc and transfers them into a segment, and then

from there to the host in accordance with the Mode Select Disconnect/Reconnect parameters, page 02h.

2. If the prefetch feature is enabled, refer to section 4.5.2 for operation from this point.

Each cache segment is actually a self-contained circular buffer whose length is an integer number of logical
blocks. The drive dynamically creates and removes segments based on the workload. The wrap-around capa­bility of the individual segments greatly enhances the cache’s overall performance.

Note. The size of each segment is not reported by Mode Sense command page 08h, bytes 14 and 15.

The value 0XFFFF is always reported regardless of the actual size of the segment. Sending a size
specification using the Mode Select command (bytes 14 and 15) does not set up a new segment
size. If the STRICT bit in Mode page 00h (byte 2, bit 1) is set to one, the drive responds as it does
for any attempt to change an unchangeable parameter.

Constellation SAS Product Manual, Rev. C 11

4.5.1 Caching write data

Write caching is a write operation by the drive that makes use of a drive buffer storage area where the data to
be written to the medium is stored while the drive performs the Write command.

If read caching is enabled (RCD=0), then data written to the medium is retained in the cache to be made avail­able for future read cache hits. The same buffer space and segmentation is used as set up for read functions.
The buffer segmentation scheme is set up or changed independently, having nothing to do with the state of
RCD. When a write command is issued, if RCD=0, the cache is first checked to see if any logical blocks that
are to be written are already stored in the cache from a previous read or write command. If there are, the
respective cache segments are cleared. The new data is cached for subsequent Read commands.

If the number of write data logical blocks exceed the size of the segment being written into, when the end of the
segment is reached, the data is written into the beginning of the same cache segment, overwriting the data that
was written there at the beginning of the operation; however, the drive does not overwrite data that has not yet
been written to the medium.

If write caching is enabled (WCE=1), then the drive may return Good status on a write command after the data
has been transferred into the cache, but before the data has been written to the medium. If an error occurs
while writing the data to the medium, and Good status has already been returned, a deferred error will be gen­erated.

The Synchronize Cache command may be used to force the drive to write all cached write data to the medium.
Upon completion of a Synchronize Cache command, all data received from previous write commands will have
been written to the medium. Table 8 shows the mode default settings for the drive.

4.5.2 Prefetch operation

If the Prefetch feature is enabled, data in contiguous logical blocks on the disc immediately beyond that which
was requested by a Read command are retrieved and stored in the buffer for immediate transfer from the buf­fer to the host on subsequent Read commands that request those logical blocks (this is true even if cache
operation is disabled). Though the prefetch operation uses the buffer as a cache, finding the requested data in
the buffer is a prefetch hit, not a cache operation hit.

To enable Prefetch, use Mode Select page 08h, byte 12, bit 5 (Disable Read Ahead - DRA bit). DRA bit = 0
enables prefetch.

The drive does not use the Max Prefetch field (bytes 8 and 9) or the Prefetch Ceiling field (bytes 10 and 11).

When prefetch (read look-ahead) is enabled (enabled by DRA = 0), the drive enables prefetch of contiguous
blocks from the disc when it senses that a prefetch hit will likely occur. The drive disables prefetch when it
decides that a prefetch hit is not likely to occur.

12 Constellation SAS Product Manual, Rev. C

5.0 Reliability specifications

The following reliability specifications assume correct host and drive operational interface, including all inter­face timings, power supply voltages, environmental requirements and drive mounting constraints.

Seek error rate: Less than 10 errors in 10
Read Error Rates

1

Recovered Data Less than 10 errors in 1012 bits transferred (OEM default settings)
Unrecovered Data Less than 1 sector in 10

Miscorrected Data Less than 1 sector in 10
Interface error rate: Less than 1 error in 10
Mean Time Between Failure (MTBF): 1,200,000 hours
Annualized Failure Rate (AFR): 0.73%
Preventive maintenance: None required

1. Error rate specified with automatic retries and data correction with ECC enabled and all flaws reallocated.

5.1 Error rates

The error rates stated in this manual assume the following:

• The drive is operated in accordance with this manual using DC power as defined in paragraph 6.3, "DC
power requirements."

• Errors caused by host system failures are excluded from error rate computations.

• Assume random data.

• Default OEM error recovery settings are applied. This includes AWRE, ARRE, full read retries, full write
retries and full retry time.

8

seeks

15

bits transferred

21

bits transferred

12

bits transferred

5.1.1 Recoverable Errors

Recoverable errors are those detected and corrected by the drive, and do not require user intervention.

Recoverable Data errors will use correction, although ECC on-the-fly is not considered for purposes of recov­ered error specifications.

Recovered Data error rate is determined using read bits transferred for recoverable errors occurring during a
read, and using write bits transferred for recoverable errors occurring during a write.

5.1.2 Unrecoverable Errors

An unrecoverable data error is defined as a failure of the drive to recover data from the media. These errors
occur due to head/media or write problems. Unrecoverable data errors are only detected during read opera­tions, but not caused by the read. If an unrecoverable data error is detected, a MEDIUM ERROR (03h) in the
Sense Key will be reported. Multiple unrecoverable data errors resulting from the same cause are treated as 1
error.

Constellation SAS Product Manual, Rev. C 13

5.1.3 Seek 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 10

8

seeks. Unrecoverable seek errors

(Sense Key = 04h) are classified as drive failures.

5.1.4 Interface 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.

5.2 Reliability and service

You can enhance the reliability of Constellation disc drives by ensuring that the drive receives adequate cool­ing. Section 6.0 provides temperature measurements and other information that may be used to enhance the
service life of the drive. Section 9.2 provides recommended air-flow information.

5.2.1 Annualized Failure Rate (AFR) and Mean Time Between Failure (MTBF)

The production disc drive shall achieve an AFR of 0.73% (MTBF of 1,200,000 hours) when operated in an
environment that ensures the HDA case temperatures do not exceed the values specified in Section 6.5. Oper­ation at case temperatures outside the specifications in Section 6.5 may increase the product AFR (decrease
the MTBF). The AFR (MTBF) is a population statistic not relevant to individual units.

The AFR (MTBF) specification is based on the following assumptions for Enterprise Storage System environ­ments:

• 8,760 power-on hours per year.

• 250 average on/off cycles per year.

• Operations at nominal voltages.

• Systems will provide adequate cooling to ensure the case temperatures specified in Section 6.5 are not
exceeded. Temperatures outside the specifications in Section 6.5 will increase the product AFR and
decrease the MTBF.

5.2.2 Preventive maintenance

No routine scheduled preventive maintenance is required.

5.2.3 Hot plugging the drive

When a disc is powered on by switching the power or hot plugged, the drive runs a self test before attempting
to communicate on its’ interfaces. When the self test completes successfully, the drive initiates a Link Reset
starting with OOB. An attached device should respond to the link reset. If the link reset attempt fails, or any
time the drive looses sync, the drive initiated link reset. The drive will initiate link reset once per second but
alternates between port A and B. Therefore each port will attempt a link reset once per 2 seconds assuming
both ports are out of sync.

If the self-test fails, the drive does not respond to link reset on the failing port.

Note. It is the responsibility of the systems integrator to assure that no temperature, energy, voltage haz-

ard, or ESD potential hazard is presented during the hot connect/disconnect operation. Discharge
the static electricity from the drive carrier prior to inserting it into the system.

14 Constellation SAS Product Manual, Rev. C

Caution. The drive motor must come to a complete stop prior to changing the plane of operation. This time is

required to insure data integrity.

5.2.4 S.M.A.R.T.

S.M.A.R.T. is an acronym for Self-Monitoring Analysis and Reporting Technology. This technology is intended
to recognize conditions that indicate imminent drive failure and is designed to provide sufficient warning of a
failure to allow you to back up the data before an actual failure occurs.

Note. The drive’s firmware monitors specific attributes for degradation over time but can’t predict instanta-

neous drive failures.

Each monitored attribute has been selected to monitor a specific set of failure conditions in the operating per­formance of the drive and the thresholds are optimized to minimize “false” and “failed” predictions.

Controlling S.M.A.R.T.

The operating mode of S.M.A.R.T. is controlled by the DEXCPT and PERF bits on the Informational Exceptions
Control mode page (1Ch). Use the DEXCPT bit to enable or disable the S.M.A.R.T. feature. Setting the DEX­CPT bit disables all S.M.A.R.T. functions. When enabled, S.M.A.R.T. collects on-line data as the drive performs
normal read and write operations. When the PERF bit is set, the drive is considered to be in “On-line Mode
Only” and will not perform off-line functions.

You can measure off-line attributes and force the drive to save the data by using the Rezero Unit command.
Forcing S.M.A.R.T. resets the timer so that the next scheduled interrupt is in two hours.

You can interrogate the drive through the host to determine the time remaining before the next scheduled mea­surement and data logging process occurs. To accomplish this, issue a Log Sense command to log page 0x3E.
This allows you to control when S.M.A.R.T. interruptions occur. Forcing S.M.A.R.T. with the RTZ command
resets the timer.

Performance impact

S.M.A.R.T. attribute data is saved to the disc so that the events that caused a predictive failure can be recre­ated. The drive measures and saves parameters once every two hours subject to an idle period on the drive
interfaces. The process of measuring off-line attribute data and saving data to the disc is uninterruptable. The
maximum on-line only processing delay is summarized below:

Maximum processing delay

On-line only delay
DEXCPT = 0, PERF = 1

S.M.A.R.T. delay times 220 milliseconds 455 milliseconds

Fully-enabled delay
DEXCPT = 0, PERF = 0

Reporting control

Reporting is controlled by the MRIE bits in the Informational Exceptions Control mode page (1Ch). Subject to
the reporting method, the firmware will issue to the host an 01-5Dxx sense code. The error code is preserved
through bus resets and power cycles.

Determining rate

S.M.A.R.T. monitors the rate at which errors occur and signals a predictive failure if the rate of degraded errors
increases to an unacceptable level. To determine rate, error events are logged and compared to the number of
total operations for a given attribute. The interval defines the number of operations over which to measure the
rate. The counter that keeps track of the current number of operations is referred to as the Interval Counter.

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S.M.A.R.T. measures error rates. All errors for each monitored attribute are recorded. A counter keeps track of
the number of errors for the current interval. This counter is referred to as the Failure Counter.

Error rate is the number of errors per operation. The algorithm that S.M.A.R.T. uses to record rates of error is to
set thresholds for the number of errors and their interval. If the number of errors exceeds the threshold before
the interval expires, the error rate is considered to be unacceptable. If the number of errors does not exceed
the threshold before the interval expires, the error rate is considered to be acceptable. In either case, the inter­val and failure counters are reset and the process starts over.

Predictive failures

S.M.A.R.T. signals predictive failures when the drive is performing unacceptably for a period of time. The firm­ware keeps a running count of the number of times the error rate for each attribute is unacceptable. To accom­plish this, a counter is incremented each time the error rate is unacceptable and decremented (not to exceed
zero) whenever the error rate is acceptable. If the counter continually increments such that it reaches the pre­dictive threshold, a predictive failure is signaled. This counter is referred to as the Failure History Counter.
There is a separate Failure History Counter for each attribute.

5.2.5 Thermal monitor

Constellation drives implement a temperature warning system which:

1. Signals the host if the temperature exceeds a value which would threaten the drive.

2. Signals the host if the temperature exceeds a user-specified value.

3. Saves a S.M.A.R.T. data frame on the drive which exceeds the threatening temperature value.

A temperature sensor monitors the drive temperature and issues a warning over the interface when the tem­perature exceeds a set threshold. The temperature is measured at power-up and then at ten-minute intervals
after power-up.

The thermal monitor system generates a warning code of 01-0B01 when the temperature exceeds the speci­fied limit in compliance with the SCSI standard. The drive temperature is reported in the FRU code field of
mode sense data. You can use this information to determine if the warning is due to the temperature exceeding
the drive threatening temperature or the user-specified temperature.

This feature is controlled by the Enable Warning (EWasc) bit, and the reporting mechanism is controlled by the
Method of Reporting Informational Exceptions field (MRIE) on the Informational Exceptions Control (IEC)
mode page (1Ch).

The current algorithm implements two temperature trip points. The first trip point is set at 65°C which is the
maximum temperature limit according to the drive specification. The second trip point is user-selectable using
the Log Select command. The reference temperature parameter in the temperature log page (see Table 1) can
be used to set this trip point. The default value for this drive is 65°C, however, you can set it to any value in the
range of 0 to 65°C. If you specify a temperature greater than 65°C in this field, the temperature is rounded
down to 65°C. A sense code is sent to the host to indicate the rounding of the parameter field.

Table 1: Temperature Log Page (0Dh)

Parameter Code Description

0000h

0001h

Primary Temperature

Reference Temperature

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