Hard Disk Failure Factors

Every one who works with computers whether it is a business or just for private use knows that the information they accumulate on their computers is stored on their hard disk drive. The data stored daily, hourly or every second is at its most current therefore if it does fail and you don’t have a current backup of that data it can be a very big problem. While it is perhaps a great annoyance for a private computer user it is a much bigger problem when this is a business computer.

There are many types of failures for hard drives and the information stored within them and we cover some of these specific failure types here.

Why does a hard disk drive fail?

A lot of these failures relate to how the data itself is stored. The data itself is stored on a circular platter which spins from between 5400 rpm to 15,000 rpm. There is a read/write head mounted on an arm that is positioned across the platter so as to access the data. This head "floats" very closely at the surface by dint of an aerodynamic effect. When you add to this any movement and the potential for heat generation there are many things that can very suddenly go wrong.

What is Media Failure?

A hard disk drive will "hide" instances of media failure so as to maintain a perfectly readable disk, and prevent operating system troubles as the result of unreadable sectors. How this is achieved is by maintaining a set of spare sectors, therefore when a failure does transpire this data is relocated to one of these spare sectors. There is however a point in time when these spare sectors can be all used and the errors will then start. Often when this point is reached the disk itself is in very bad condition and close to the point of imminent failure. At this point, if the disk is continued to run in this state the problems then will rapidly increase.

What is a Head Crash?

This term relates to when the head itself touches the surface of the platter whilst it is spinning. This can occur as the result of an impact or perhaps a mechanical failure within the HDA. HDA stands for Head Disk Assembly and is comprised of the head/platter combination. In the worst cases this contact can strip away the whole recorded surface of the platter leaving only the base material which is typically glass.

What is Bearing Seizure?

The rotation of the platter must be nice and smooth. When there is any unusual or unexpected vibration this can cause positional problems. If there is any impact, or after prolonged use these bearings that permit the platter to rotate can crumble and seize. When this occurs the drive itself can not spin the platter and therefore no data can be read.

What is Electronic Failure?

Hard drives are controlled by circuitry. This circuitry is vulnerable to damage from electrostatic discharge or electrical surges. If a component is near to the point of failure then often a relatively minor electrical "blip" will tip the scales between continued operation and electrical failure. The difficulty with a hard drive is that it has information and code stored within the memory devices on the drive controller. This is created when the drive is first formatted therefore just replacing the electronics will not solve the problem.

What are Data Failures?

In some cases the problem is not actually with the disk itself but more with the system or the person using the system that is creating the problem. When there is a disappearance of files or a partition of files this could be a user error or an application error and the disk itself may in fact be working perfectly. A data recovery specialist can assist in this diagnosis.

What to do in any of these instances:

Hard disk data recovery is a job for the experts. The term itself is related to a variety of techniques to retrieve the data from a failed device and locating a suitable way to retrieve the data in a usable format. The most important thing to be aware of is that there is no 100% guarantee that your information will be retrievable and there are a variety of factors, as listed above that may in fact be the cause of your data loss. A data recovery expert will do their best to locate and retrieve your data however it is possible that your data may well in fact be gone.