Seagate ST400FX0002 Pulsar XT.2 SAS Product Manual - Page 26

18

Pulsar XT.2 SAS Product Manual, Rev. B

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 appropriate 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 firm-

ware keeps a running count of the number of times the error rate for each attribute is unacceptable. To accom-

plish 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 pre-

dictive 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.

6.3.5

Thermal monitor

Pulsar XT.2 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. (i.e., the reference temperature 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 tem-

perature 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 speci-

fied limit in compliance with the SCSI standard. The drive temperature is reported in the FRU code field of

MODE SENSE data. Administrators can use this information to determine if the warning is due to the tempera-

ture 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 the maximum temper-

ature 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 7) can be used to set

this trip point. The default value for this drive is listed in the table, however, applications can set it to any value

in the range defined. If a temperature is specified that is greater than the maximum allowed in this field, the

temperature is rounded down to the maximum allowed. A sense code is sent to the host to indicate the round-

ing of the parameter field.

Table 7:

Temperature Log Page (0Dh)

Parameter Code

Description

400GB

200/100GB

0000h

Primary Temperature

Drive Temperature

0001h

Reference Temperature

Default Setting

70

°

C

65

°

C

Changeable Range

0 to 70

°

C

0 to 65

°

C

Section	Page
1.0 Seagate Technology support services	9
2.0 Scope	10
3.0 Applicable standards and reference documentation	11
3.1 Standards	11
3.1.1 Electromagnetic compatibility	11
3.1.1.1 Electromagnetic susceptibility	11
3.1.2 Electromagnetic compliance	12
3.1.3 European Union Restriction of Hazardous Substances (RoHS)	12
3.1.4 China Restriction of Hazardous Substances (RoHS) Directive	13
3.2 Reference documents	13
4.0 General description	14
4.1 Standard features	14
4.2 Media description	15
4.3 Performance	15
4.4 Reliability	15
4.5 Formatted capacities	16
4.6 Programmable drive capacity	16
4.7 Factory-installed options	16
4.8 Thin Provisioning	17
4.8.1 Logical Block Provisioning	17
4.8.2 Thin Provisioning capabilities	17
4.8.3 UNMAP	17
4.8.4 FORMAT UNIT command	17
4.8.5 Protection Information (PI) and Security (SED)	17
5.0 Performance characteristics	19
5.1 Internal drive characteristics	19
5.2 Performance characteristics	19
5.2.1 Access time	19
5.2.2 FORMAT UNIT command execution time for 512-byte LBA’s (minutes)	20
5.2.3 Performance	20
5.3 Start/stop time	21
5.4 Cache control	21
5.4.1 Caching write data	21
6.0 Reliability specifications	22
6.1 Error rates	22
6.1.1 Unrecoverable Errors	23
6.1.2 Interface errors	23
6.2 Endurance Management	23
6.2.1 Wear Leveling	23
6.2.2 Garbage Collection	23
6.2.3 Write Amplification	23
6.2.4 UNMAP	23
6.2.5 Data Retention	24
6.2.6 Lifetime Endurance Management	24
6.3 Reliability and service	24
6.3.1 Annualized Failure Rate (AFR) and Mean Time Between Failure (MTBF)	24
6.3.2 Preventive maintenance	24
6.3.3 Hot plugging the drive	24
6.3.4 S.M.A.R.T.	25
6.3.5 Thermal monitor	26
6.3.6 Drive Self Test (DST)	27
6.3.6.1 DST failure definition	27
6.3.6.2 Implementation	27
6.3.7 Product warranty	29
7.0 Physical/electrical specifications	30
7.1 Power specifications	30
7.1.1 Power consumption	30
7.2 AC power requirements	30
7.3 DC power requirements	31
7.3.1 Conducted noise immunity	34
7.3.2 Power sequencing	34
7.3.3 Current profiles	34
7.4 Power dissipation	36
7.5 Environmental limits	37
7.5.1 Temperature	37
7.5.2 Relative humidity	38
7.5.3 Effective altitude (sea level)	38
7.5.4 Shock and vibration	38
7.5.4.1 Shock	39
7.5.4.2 Vibration	40
7.5.5 Air cleanliness	40
7.5.6 Corrosive environment	40
7.5.7 Electromagnetic susceptibility	40
7.6 Mechanical specifications	41
8.0 About self-encrypting drives	43
8.1 Data encryption	43
8.2 Controlled access	43
8.2.1 Admin SP	43
8.2.2 Locking SP	44
8.2.3 Default password	44
8.3 Random number generator (RNG)	44
8.4 Drive locking	44
8.5 Data bands	44
8.6 Cryptographic erase	45
8.7 Authenticated firmware download	45
8.8 Power requirements	45
8.9 Supported commands	45
8.10 RevertSP	45
9.0 Defect and error management	46
9.1 Drive internal defects/errors	46
9.2 Drive error recovery procedures	47
9.3 SAS system errors	47
9.4 Background Media Scan	47
9.5 Auto-Reallocation	47
9.6 Protection Information (PI)	48
9.6.1 Levels of PI	48
9.6.2 Setting and determining the current Type Level	48
9.6.3 Identifying a Protection Information drive	48
10.0 Installation	49
10.1 Drive orientation	49
10.2 Cooling	50
10.3 Drive mounting	51
10.4 Grounding	51
11.0 Interface requirements	52
11.1 SAS features	52
11.1.1 Task management functions	52
11.1.2 Task management responses	52
11.2 Dual port support	53
11.3 SCSI commands supported	54
11.3.1 INQUIRY data	58
11.3.2 MODE SENSE data	58
11.4 Miscellaneous operating features and conditions	63
11.4.1 SAS physical interface	63
11.4.2 Physical characteristics	66
11.4.3 Connector requirements	66
11.4.4 Electrical description	66
11.4.5 Pin descriptions	66
11.4.6 SAS transmitters and receivers	67
11.4.7 Power	67
11.5 Signal characteristics	67
11.5.1 Ready LED Out	67
11.5.2 Differential signals	68
11.6 SAS-2 Specification compliance	68
11.7 Additional information	68
Numerics	69
A	69
B	69
C	69
D	69
E	69
F	70
G	70
H	70
I	70
J	70
L	70
M	70
N	71
O	71
P	71
Q	71
R	71
S	71
T	72
U	72
V	72
W	72

Seagate ST400FX0002 Pulsar XT.2 SAS Product Manual - Page 26

Predictive failures, Thermal monitor, Table 7, Temperature Log Dh, Parameter Code, Description

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