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

Barracuda ES.2 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

18

Barracuda ES.2 FC Product Manual, Rev. B

Page 26
Image 26
Seagate ES.2 FC, ST31000640FC manual Reporting control, Determining rate, Predictive failures, Thermal monitor

ST31000640FC, ES.2 FC specifications

The Seagate ES.2 FC, model ST31000640FC, is a high-performance hard drive designed specifically for enterprise environments. This drive is engineered to provide reliable and efficient data storage, catering to the demands of critical business applications, data centers, and server infrastructures.

One of the standout features of the ST31000640FC is its large storage capacity. With a 1TB capacity, it offers ample space for storing vast amounts of data, making it an excellent choice for businesses that require extensive storage solutions. This capacity enables the drive to support extensive databases, applications, and virtualized environments without compromising performance.

The Seagate ES.2 FC utilizes Fibre Channel (FC) interface technology, which is known for its high-speed data transfer capabilities. Operating at 4 Gbps, this interface facilitates faster communication between the drive and the server, significantly enhancing overall system performance. The Fibre Channel technology also improves data integrity through its ability to manage large amounts of data traffic efficiently.

In terms of performance specifications, the ST31000640FC boasts a rotational speed of 7200 RPM and a sustained data transfer rate that offers quick access to information. Additionally, it features an advanced caching mechanism that optimizes read and write operations, ensuring rapid data retrieval and improved application responsiveness.

The drive's advanced error recovery and data protection mechanisms, such as the Seagate PowerTrim technology, work to minimize downtime and data loss. This is particularly crucial for enterprise applications that demand high availability and reliability. PowerTrim intelligently manages the drive’s internal resources to enhance performance and durability.

Another essential characteristic of the Seagate ES.2 FC is its enterprise-grade reliability. It boasts a mean time between failures (MTBF) rating of 1.2 million hours, indicating its robustness for continuous operation in demanding environments. Furthermore, it is designed to operate in a range of temperatures, ensuring consistent performance across various operational conditions.

Lastly, the Seagate ES.2 FC incorporates vibration tolerance and advanced acoustic performance features, which help to reduce noise and ensure quieter operation in data center environments. This makes it an attractive option for enterprises looking to optimize their infrastructure while minimizing disturbances.

In summary, the Seagate ES.2 FC, ST31000640FC hard drive is an excellent choice for enterprises seeking a balance of large storage capacity, high-speed performance, and reliability in a Fibre Channel environment. With its array of technologies and robust characteristics, it meets the rigorous demands of modern business storage needs.