What is a fail soft system? Definition and examples

A Fail Soft System is one that shuts down non-essential functions when something goes wrong. The system can still function at a basic level. Its basic function may help the user either fix it or take it to somebody who can. We can use the term for a machine, vehicle, or component. We can also use it for computer systems, other systems, and many types of equipment.

In power grids, fail soft protocols help isolate faults, ensuring that even during a partial outage, essential services like hospitals continue to receive electricity.

With a fail soft system, the computer software, for example, fails selectively. In other words, it selects specific functions to shut down.

However, it keeps the essential or primary functions going. Therefore, as in the case of a computer, the software can continue working, but at reduced capacity.

We can write the term with or without a hyphen, i.e., ‘fail soft‘ or ‘fail-soft.’

Webopedia.com has the following definition of the term:

“Used to describe systems that are designed to terminate any nonessential processing when there are hardware or software failures.”

“Systems in fail soft mode are still able to provide partial operational capability.”

Fail Soft System

Computer Hope says that people design a fail soft system so that non-essential components shut down in the event of a failure. However, the computer system and programs continue running.

Fail soft vs. fail-safe

Do not confuse the term with fail-safe.

  • Fail-safe

A fail-safe is a mechanism in a system or machine that allows it to ‘fail safely.’

For example, lawnmowers have a lever that the user must hold down. If the user lets go of that lever, the lawnmower stops.

That lever is a fail-safe. It is there to protect you and other people. Let’s suppose, for example, that you are mowing your lawn and suddenly lose consciousness. Your hand lets go of the lever.

The machine will subsequently shut down. By shutting down, it is protecting you and other people.

We also call that lever a ‘dead man’s switch.’ Many trains have a dead man’s switch. If something happens to the train driver and they release the switch, the train will stop.

  • Fail-soft system

This is a system that continues operating at a basic level when there is a fault or malfunction.

Many vehicle spare tires (UK: tyres), for example, have this. They usually come with a speed restriction which leads to poorer fuel economy. However, the driver can get the vehicle to a workshop or home.

In the world of computers, all Windows operating systems have a ‘Safe Mode.’ In that mode, you can do very basic things.

Fail soft strategies are also vital in network management, allowing communication systems to remain partially operational, ensuring critical data transmission during outages.

Fail soft mechanisms – examples

Below you can see five more examples of fail soft mechanisms, plus how they can be used in a spoken sentence:

  • Traffic Light Systems

During a power outage or malfunction, traffic lights can switch to a flashing red or yellow state, maintaining basic traffic control.
Example Sentence: “When the main traffic signal failed, the fail soft mechanism activated, and the lights switched to blinking yellow, urging caution at the intersection.”

  • Database Management Systems (DBMS)

On encountering errors, a DBMS may go into a restricted mode, allowing read access but preventing changes to protect data integrity.
Example Sentence: “The database entered a fail soft state after the update glitch, allowing users to query data but blocking any new transactions.”

  • Robotic Manufacturing Arms

If a sensor detects a fault, the arm may freeze or slow down movements to prevent damage to itself or the product.
Example Sentence: “The robotic arm’s fail soft response to the jammed component prevented further damage to the assembly line.”

  • Financial Trading Platforms

In case of extreme volatility, some trading platforms have mechanisms to pause trading on a particular stock, preventing potential market crashes.
Example Sentence: “As stock prices became erratic, the fail soft system paused trading, activating a temporary halt to restore order to the market.”

  • Cloud Storage Services

When server errors occur, cloud services may limit access to file editing but still allow file viewing and downloading.
Example Sentence: “After the server hiccup, our cloud storage entered a fail soft mode, ensuring we could still access and download our documents safely.”

Video – What is a Fail Soft System?

This video, from our sister channel on YouTube – Marketing Business Network, explains what a ‘Fail Soft System’ is using simple and easy-to-understand language and examples.