How long should a hard drive last?

There are many factors which can affect the life of a hard drive. Some drives are designed to last longer than others. And some drives are designed for special uses, such as in automobiles where vibration can be a problem. Modern hard drives have multiple platters that spin at high rates of speed and have read/write heads on both sides of each platter that travel a few nanometers (billionths of a meter) from the surface. In addition to the increasing speeds, the data on the disk is packed closer together to increase capacity. The technology behind modern disk storage devices is truly amazing, the tolerances are so close that the drives automatically adjust themselves every few minutes to compensate for temperature changes that will cause the platters and assemblies to expand and contract which affect the distance the head must travel to find the bit of data requested. These advances in technology have given us much greater capacities and performance, while reliability has generally improved as well. Hard drives are not simple technology and lot can go wrong. And will go wrong.

Drives are designed and manufactured with differing design objectives. Price is major factor in the design of drives for consumer goods, such as personal computers. If you buy a cheap computer, then you can't expect it to have the most expensive hard drive that was designed for longer life. However, in my opinion, you shouldn't be overly concerned about the quality of the HD inside the computer you are buying, they are all quite good. But just keep in mind that whatever the brand and model, the drive will eventually wear out and you can't reliably predict when it will fail.

The computer itself, has a lot to do with the life of the hard drive inside. Major brand servers for example concentrate a fair amount of engineering towards airflow and cooling. The operating temperature of a hard drive can have dramatic effects on the life of the drive. An overheating drive can easily fail within days or weeks of first use, while a well cooled drive can last for years. Desktop and workstation computers have certain requirement for quietness. People generally don't like loud computers, which causes the designers to have to make some trade-offs between airflow and noise. Laptop computers are especially problematic because there is not much room in the case for air and fans. Laptops have proliferated over the last few years and are outselling desktop computers. This puts more of our data a risk because the drives in laptop computers are generally not cooled as well and they are also more subject to vibration and shock as the are mobile.

IT professionals are well aware that all disk drives will fail and therefore they store all critical data on fault tolerant disk arrays. These arrays can withstand one or more failures of individual drives without the loss of any data. Even with the use of arrays, the professionals always backup critical data and store a backup copy off-site in a secure location. In fact, all IT auditing practices require that data is backed up and stored securely off-site.

Hard drives do a wonderful job of storing your data and making it available for use quickly and reliably. However, they cannot guarantee that your data will not be lost. The only way to make sure your data will not be lost is to backup your data on a regular basis. Best practices will have you store a copy of your backup data off-site, preferably in a secure location that will not be affected by any disaster that may destroy your home or office.

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