Boosting HDD Lifespan

By Rainer W. Kaese, senior manager, business development storage products Toshiba Electronics Europe.

Modern enterprise HDDs are highly reliable and may generally be used beyond their warranty period without any issues and no significant increase in failure rates. However, this is dependent on the drives being well-maintained and operated under optimal conditions. If not, the likelihood of failure rises considerably. But what constitutes optimal operating conditions, and what should companies be mindful of if they wish to maximise the lifespan of their HDDs?

Firstly, HDDs require a stable and consistent operation, as they contain moving parts that can be damaged by movements or shocks. Systems equipped with HDDs are therefore best housed securely in a rack. Tower-format devices, which cannot be accommodated in a rack, should be placed in a location where they are not at risk of being accidentally knocked or kicked, and certainly not on a desk, where the tabletop can act as a sounding board, transmitting any vibrations directly to the devices.

Furthermore, the HDDs must be securely fastened within the device. Merely placing them inside the casing can lead to minor movements of the drive due to the rapidly spinning disks inside, which may cause damage. Particularly in more affordable systems, manufacturers often use plastic clamps or bays that allow for some ‘give‘ in the HDDs or are themselves not completely secure within the casing. In such cases, it is advisable to properly secure the HDDs and bays, for example, with small rubber pieces or use additional screws, if possible.

High Temperatures Shorten Lifespan
Enterprise HDDs are designed to operate at temperatures between 5°C and 60°C. However, this only means that they will function correctly within this range – at higher temperatures, the electronic and mechanical components, such as the spindle bearings, wear out more quickly. Operating at the upper end of the specified range is not ideal either, as it can lead to a higher probability of failure.

The Mean Time To Failure (MTTF) listed in the datasheets refers to an average operating temperature of no more than 40°C. For most enterprise HDDs, this is 2.5 million hours, corresponding to an Annualised Failure Rate (AFR) of 0.35%. This means that out of 1,000 drives, 3 to 4r are expected to fail over the course of a year. At temperatures above 40°C, the failure rate increases – typically by about 30% for every 5°C rise in temperature. Therefore, continuous operation of HDDs at 55°C can raise the average failure rate (AFR) to 0.76%, leading to the expected failure of seven to eight drives within a year.

Overloading Increases Wear and Tear
Furthermore, usage also affects the lifespan of HDDs, as they are designed for a specific operational duration and workload. In the case of desktop drives, this is typically 16 hours/day and 55 TB/year – these models are unsuitable for NAS systems and servers, where they run 24/7 and are subjected to higher workloads. On the other hand, NAS and enterprise HDDs can handle round-the-clock operation and manage 180TB and 550TB, respectively. It doesn’t matter whether the data is being written or read.

Suppose companies want to maximise the lifespan of their HDDs. In that case, they should ensure not to exceed the specified workloads, protect the drives from shocks and vibrations, and operate them consistently at no more than 40°C on average over their lifetime. Then, using them beyond the warranty period is usually not an issue – however, regular backup becomes even more important.