Hitachi HDS723020BLA642 manual Security Mode Feature Set

Models: HDS723020BLA642

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7K200 SATA OEM Specification

the device are predicting a lower probability of a degrading or fault condition existing. Accordingly, lower attribute values indicate that the analysis algorithms being used by the device are predicting a higher probability of a degrading or fault condition existing. There is no implied linear reliability relationship corresponding to the numerical relationship between different attribute values for any particular attribute.

12.8.3Attribute thresholds

Each attribute value has a corresponding attribute threshold limit which is used for direct comparison to the attribute value to indicate the existence of a degrading or faulty condition. The numerical value of the attribute thresholds are determined by the device manufacturer through design and reliability testing and analysis. Each attribute threshold represents the lowest limit to which its corresponding attribute value can be equal while still retaining a positive reliability status. Attribute thresholds are set at the device manufacturer’s factory and cannot be changed in the field. The valid range for attribute thresholds is from 1 through 253 decimal.

12.8.4Threshold exceeded condition

If one or more attribute values are less than or equal to their corresponding attribute thresholds, then the device reliability status is negative, indicating an impending degrading or faulty condition.

12.8.5S.M.A.R.T. commands

The S.M.A.R.T. commands provide access to attribute values, attribute thresholds and other logging and reporting information.

12.8.6S.M.A.R.T operation with power management modes

The device saves attribute values automatically on every head unload timing except the emergency unload, even if the attribute auto save feature is not enabled. The head unload is done not only by Standby, Standby Immediate, or Sleep command, but also by the automatic power saving functions like ABLE-3 or Standby timer. So basically it is not necessary for a host system to enable the attribute auto save feature, when it utilizes the power management. If the attribute auto save feature is enabled, attribute values will be saved after 30minutes passed since the last saving, besides above condition.

12.9 Security Mode Feature Set

Security Mode Feature Set is a powerful security feature. With a device lock password, a user can prevent unauthorized access to hard disk device even if the device is removed from the computer.

New commands are supported for this feature as below.

Security Set Password

(‘F1’h)

Security Unlock

(‘F2’h)

Security Erase Prepare

(‘F3’h)

Security Erase Unit

(‘F4’h)

Security Freeze Lock

(‘F5’h)

Security Disable Password

(‘F6’h)

12.9.1Security mode

Following security modes are provided.

Device Locked mode

The device disables media access commands after power on. Media access

 

commands are enabled by either a security unlock command or a security

 

erase unit command.

Device Unlocked mode

The device enables all commands. If a password is not set this mode is

 

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Hitachi HDS723020BLA642 manual Security Mode Feature Set