hardScenarioConceptMidSeniorStaff
A dashboard has been showing the same temperature for two days and nobody noticed. Walk the path and tell me what would have caught it.
6 min readUpdated 2026-08-15
Answer
Short answer
On any protocol that reports by exception, no new value and an unchanged value look identical, so liveness has to be carried deliberately. Status codes, source timestamps, birth and death messages and a source-side counter each establish it at a different layer of the path.
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