Fault tolerance is a process that enables an operating system to respond to a failure in hardware or software. This fault-tolerance definition refers to the system’s ability to continue operating despite failures or malfunctions.
An operating system that offers a solid definition for faults cannot be disrupted by a single point of failure. It ensures business continuity and the high availability of crucial applications and systems regardless of any failures.
Fault tolerance is reliant on aspects like load balancing and failover, which remove the risk of a single point of failure. It will typically be part of the operating system’s interface, which enables programmers to check the performance of data throughout a transaction.
The key benefit of fault tolerance is to minimize or avoid the risk of systems becoming unavailable due to a component error. This is particularly important in critical systems that are relied on to ensure people’s safety, such as air traffic control, and systems that protect and secure critical data and high-value transactions.
It enables a system to continue its intended operation, possibly at a reduced level, rather than failing completely, when some part of the system fails. The term is most commonly used to describe computer systems designed to continue more or less fully operational with, perhaps, a reduction in throughput or an increase in response time in the event of some partial failure. That is, the system as a whole is not stopped due to problems either in the hardware or the software. An example in another field is a motor vehicle designed so it will continue to be drivable if one of the tires is punctured, or a structure that is able to retain its integrity in the presence of damage due to causes such as fatigue, corrosion, manufacturing flaws, or impact.
A twin-engine airplane is a fault tolerant system if one engine fails, the other one kicks in, allowing the plane to continue flying is another example of a fault tolerant system.
