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single point of failure
The one box, file, or person whose death takes the system with it. Name it before you draw more boxes.
What is single point of failure?
A single point of failure is a component with no standby. One database with no replica, one NAT, one certificate on one laptop, one queue with one consumer on one disk. Redundancy is a second thing that can take over, not a second arrow in a slide.
Why does single point of failure matter when vibe coding?
Models add a second app server and leave one database, one cache, and one availability zone. The diagram looks distributed. The failure domain did not change. Ask what dies alone.
How do you do single point of failure?
List components that are count one. For each, say the standby or explicitly accept the outage. A replica you have never failed over to is not a standby yet.
How do you ask a model for single point of failure?
List single points of failure for (system). For each, add a real standby or write down that we accept the outage. Do not call it redundant unless failover has a path.
What goes wrong with single point of failure?
Two instances in the same zone on the same disk. That is one failure with two processes.