Non-current Hard Disk Technologies - Digital Preservation Coalition


Materials saved to storage devices with a variety of underlying magnetic or solid-state technologies that are hardwired into a computer that is no longer under warranty or supported: typically, hard disks more than five years old.
Group: Integrated Storage	Trend in 2021:	Consensus Decision
Added to List: 2019	Trend towards greater risk	Previous classification: Critically Endangered
	Trend in 2022:
	No Change
Imminence of Action Action is recommended within twelve months, detailed assessment is a priority.	Significance of Loss The loss of tools, data or services within this group would impact on people and sectors around the world.	Effort to Preserve It would require a small effort to prevent losses in this group, such as the deployment of proven preservation tools or techniques
Examples Disks installed into computers or servers that are more than five years old, or out of warranty
‘Practically Extinct’ in the Presence of Aggravating Conditions Lack of replication; poor storage; non-standard connections or controllers; aggressive compression; encryption
‘Endangered’ in the Presence of Good Practice Maintenance schedule; renewable extendable warranty; best practice storage and operation; replication
2021 Review This entry was added in 2019 to ensure that the range of media storage is properly assessed and presented. The lifecycles of most consumer hard disk technology are relatively stable in comparison to portable devices because they are integrated into systems and therefore inherit the lifecycle and replacement of the entire system. This is less true at scale; however, where disks are used in storage arrays, and refreshment is more loosely tied to the server architecture. Storage at scale also means the percentage likelihood of finding a disk failure increases, and this likelihood of failure led to the 2021 Jury’s noted trend towards greater risk.
Additional Comments The greater density of newer disks, as well as encryption and compression, mean they can be more fragile than older disks with less density, and less sophisticated read/write technologies. The age of a disk is not the best or only indicator of its reliability.