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 inter- val 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.

6.2.5Thermal monitor

Constellation ES 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 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. 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

Primary Temperature

 

 

0001h

Reference Temperature

 

 

Constellation ES Series SAS Product Manual, Rev. F

17

Page 25
Image 25
Seagate ST2000NM0053 manual Predictive failures, Thermal monitor, Temperature Log Page 0Dh Parameter Code Description

ST4000NM0053, ST4000NM0023, ST32000444SSIM, ST32000646NS, ST3000NM0063 specifications

Seagate is a prominent name in the storage industry, renowned for its high-performance hard disk drives (HDDs). Among its popular enterprise offerings are models like the ST2000NM0043, ST32000645NS, ST3000NM0043, ST2000NM0033, and ST2000NM0023, which cater to various data center and server needs.

The Seagate ST2000NM0043 is a 2TB 7200 RPM SATA drive designed for high availability and performance in enterprise environments. It features a 128MB cache, ensuring efficient data transfer speeds and quick access to frequently used data. This model boasts a mean time between failures (MTBF) of 1.4 million hours, emphasizing its reliability for continuous operation in demanding applications.

The ST32000645NS, offering 2TB of storage and a 7200 RPM spindle speed, is ideal for environments where large amounts of data need to be stored and accessed quickly. It supports SAS interfaces, providing enhanced data integrity and improved system performance. With its aggressive power management features, this model strikes a balance between performance and energy efficiency, making it suitable for both traditional data centers and cloud applications.

The ST3000NM0043 stands out with a capacity of 3TB, further addressing the growing need for more substantial storage solutions. Like its counterparts, it operates at 7200 RPM and is equipped with advanced caching mechanisms that help enhance overall performance. Its high durability and enterprise-grade features make it a preferred choice for storage-intensive applications.

The ST2000NM0033 focuses on delivering storage solutions for environments needing both capacity and reliability. With its 2TB capacity and 7200 RPM rotation speed, it provides an effective solution for businesses looking to balance workload and storage needs without compromising performance. This model also features Seagate's advanced technology that optimizes workflow and minimizes latency.

Lastly, the ST2000NM0023 mirrors many of the features found in its siblings, offering a 2TB capacity and optimized for high reliability and performance. With Seagate's commitment to innovating in the HDD space, features such as self-monitoring, analysis, and reporting technology (SMART) help maintain the drive's health and prevent potential failures.

In conclusion, Seagate's range of HDDs, exemplified by the ST2000NM0043, ST32000645NS, ST3000NM0043, ST2000NM0033, and ST2000NM0023, reflects a dedication to providing robust, high-capacity storage solutions. Their advanced technologies, reliability ratings, and performance features make them ideal choices for enterprise environments demanding efficiency and durability.