Ultrastar 7K2
HGST Hard Disk Drive Technical Reference Manual
30
Reliability Features Set
Data Lifeguard™
*
Representing the ongoing commitment to data protection, Data Lifeguard includes features that enhance
the drive’s ability to prevent data loss. Data Lifeguard data protection utilities include thermal
management, an environmental protection system, and embedded error detection and repair features that
automatically detect, isolate, and repair problem areas that may develop over the extended use of the
drive. With these enhanced data reliability features, the drive can perform more accurate monitoring, error
repair, and deliver exceptional data security.
Thermal Management
The drive is designed with Thermal Management features for high reliability.
State-of-the-art mechanical design
—Mechanical design is optimized to reduce the drive’s
temperature. State-of-the-art thermal dissipation and windage design is employed.
Closed loop servo management
—Thermal management monitors the drive temperature and can
control servo operations to maintain a stable operating temperature under high temperature
conditions. This is a closed loop servo and thermal control system.
SMART HDA Temperature Attribute
—The SMART HDA Temperature Attribute is
supported.
Ducted airflow
—Provides protection to the Read/Write element from heated air.
Internal Environmental Protection System
This system protects the inside environment of the drive from contamination. System features include:
Filtration System to ensure fast clean-up times
Directed airflow to maximize mechanical cooling
Increase casting surface area to maximize cooling
Breather filter located at low pressure area
Enhanced heat dissipation
Defect Management
Every HGST drive undergoes factory-level intelligent burn in, which thoroughly tests for and maps out
defective sectors on the media before the drive leaves the manufacturing facility. Following the factory
tests, a primary defect list is created. The list contains the cylinder, head, and sector numbers for all defects.
Defects managed at the factory are sector slipped. Grown defects that can occur in the field are mapped out
by relocation to spare sectors on the inner cylinders of the drive.
Recoverable Errors
When a sector is recovered by firmware it is marked as needing repair. When a new host command writes to
that sector, a sector test is performed by writing and reading to that location several times. If recovery is
required to read the sector during the sector test, it is relocated.
Unrecoverable Errors
If an unrecoverable error is found during the offline scan, the sector is marked. Future reads from this
location will continue to perform full error recovery. However, the next write to this location will perform a
sector test to be sure the media is not damaged, and the sector relocated if the sector test fails.
* Default shipping configuration has Data Lifeguard feature disabled for power management optimization.
