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A fault tree diagram. Fault tree analysis (FTA) is a type of failure analysis in which an undesired state of a system is examined. This analysis method is mainly used in safety engineering and reliability engineering to understand how systems can fail, to identify the best ways to reduce risk and to determine (or get a feeling for) event rates of a safety accident or a particular system level ...
Failure mode and effects analysis (FMEA; often written with "failure modes" in plural) is the process of reviewing as many components, assemblies, and subsystems as possible to identify potential failure modes in a system and their causes and effects. For each component, the failure modes and their resulting effects on the rest of the system ...
The first piece of information added in an FMEDA is the quantitative failure data (failure rates and the distribution of failure modes) for all components being analyzed. The second piece of information added to an FMEDA is the probability of the system or subsystem to detect internal failures via automatic on-line diagnostics.
For each component and failure mode, the ability of the system to detect and report the failure in question is analyzed. One of the following will be entered on each row of the FMECA matrix: Normal: the system correctly indicates a safe condition to the crew; Abnormal: the system correctly indicates a malfunction requiring crew action
Given an initial state in a state machine, a fail-fast system will check such a state and fail fast. Given a state-change in a state machine, the fail-fast system will halt the machine if the state-change is forbidden. It could be the case that the forbidden state-change is due to a wrong external input.
Fault containment to prevent propagation of the failure – Some failure mechanisms can cause a system to fail by propagating the failure to the rest of the system. An example of this kind of failure is the "rogue transmitter" that can swamp legitimate communication in a system and cause overall system failure. Firewalls or other mechanisms ...
The book depicts the failure detector as a tool to improve consensus (the achievement of reliability) and atomic broadcast (the same sequence of messages) in the distributed system. In other words, failure detectors seek errors in the process, and the system will maintain a level of reliability. In practice, after failure detectors spot crashes ...
System call; Message passing; Operating systems are designed with one or the other of these two facilities, but not both. First, assume that a user process wishes to invoke a particular target system function. For the system call approach, the user process uses the trap instruction.