Pick one and press Start, then click Next › to step through it.
The state moving Closed → Open (fail fast) → Half-Open (cautious trial) → Closed — and requests being rejected instantly while Open.
How a circuit breaker protects a failing dependency by failing fast, and how it cautiously tests recovery.
A rolling window counts recent failures. Cross the threshold and it stops calling the dependency at all, erroring immediately instead. A timer later permits a trial call or two, whose outcome decides whether normal traffic resumes or it backs off again.