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.

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.

5.2.5Thermal monitor

Cheetah 15K.5 FC 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 68°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

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Cheetah 15K.5 FC Product Manual, Rev. D

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Seagate ST3300655FC, ST3146855FC, ST373455FC manual Reporting control, Determining rate, Predictive failures, Thermal monitor
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ST3146855FC, ST373455FC, ST3300655FC specifications

Seagate is renowned for its commitment to high-performance data storage solutions, and their range of enterprise drives, including the ST3300655FC, ST373455FC, and ST3146855FC, demonstrates this dedication. These models cater to businesses requiring robust, reliable, and efficient hard disk drives (HDDs) designed for demanding environments.

The ST3300655FC offers a capacity of 300 GB, making it suitable for a variety of enterprise applications. It utilizes a 15,000 RPM spindle speed, which significantly enhances its performance, delivering quick read and write times. This drive supports Serial Attached SCSI (SAS) interface, ensuring faster data transfer rates and reliability essential for critical computing environments. The dual-port connectivity of SAS allows for enhanced fault tolerance and redundancy, making the ST3300655FC ideal for data centers and enterprise storage systems.

Following closely, the ST373455FC provides a slightly larger capacity of 734 GB while maintaining the same 15,000 RPM speed. This drive's design focuses on high availability, making it an excellent choice for applications that require continuous uptime. Like its counterpart, it also benefits from the SAS interface, ensuring that data can be accessed quickly and reliably. The robust construction of the ST373455FC guarantees consistent performance under heavy workloads, an essential characteristic for enterprise use.

The ST3146855FC, with a capacity of 146 GB, offers a balance between speed and storage for enterprises that do not require the larger capacities provided by the other two models. It also operates at 15,000 RPM, benefiting from similar technological advancements as the ST3300655FC and ST373455FC. This drive maintains compatibility with existing systems, making it a versatile option for organizations looking to upgrade their storage solutions without overhauling their infrastructure.

All three models exhibit Seagate's commitment to durability and low power consumption, which is critical for reducing operational costs in data centers. They also feature advanced error recovery and data integrity technologies, ensuring that critical data remains intact and accessible. Enhanced thermal and vibration tolerance further extends the lifespan of these drives in challenging environments.

In summary, the Seagate ST3300655FC, ST373455FC, and ST3146855FC are tailored to meet the rigorous demands of enterprise environments. Their high spindle speeds, SAS connectivity, and robust designs make them exemplary choices for businesses seeking reliable and efficient storage solutions. Their distinctive features and technologies ensure that they deliver outstanding performance, data integrity, and durability, making them invaluable assets in any data-driven organization.
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